Tissue thickness compensator comprised of a plurality of materials

[0001] The present invention relates to surgical instruments and, in various embodiments, to surgical cutting and stapling instruments and staple cartridges therefor that are designed to cut and staple tissue.

[0206] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate certain embodiments of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

[0207] The Applicant of the present application also owns the U.S. Patent Applications identified below which are each herein incorporated by reference in their respective entirety:

[0208] U.S. patent application Ser. No. 12/894,311, entitled SURGICAL INSTRUMENTS WITH RECONFIGURABLE SHAFT SEGMENTS, now U.S. Pat. No. 8,763,877;

[0209] U.S. patent application Ser. No. 12/894,340, entitled SURGICAL STAPLE CARTRIDGES SUPPORTING NON-LINEARLY ARRANGED STAPLES AND SURGICAL STAPLING INSTRUMENTS WITH COMMON STAPLE-FORMING POCKETS, now U.S. Pat. No. 8,899,463;

[0210] U.S. patent application Ser. No. 12/894,327, entitled JAW CLOSURE ARRANGEMENTS FOR SURGICAL INSTRUMENTS, now U.S. Pat. No. 8,978,956;

[0211] U.S. patent application Ser. No. 12/894,351, entitled SURGICAL CUTTING AND FASTENING INSTRUMENTS WITH SEPARATE AND DISTINCT FASTENER DEPLOYMENT AND TISSUE CUTTING SYSTEMS, now U.S. Pat. No. 9,113,864;

[0212] U.S. patent application Ser. No. 12/894,338, entitled IMPLANTABLE FASTENER CARTRIDGE HAVING A NON-UNIFORM ARRANGEMENT, now U.S. Pat. No. 8,864,007;

[0213] U.S. patent application Ser. No. 12/894,369, entitled IMPLANTABLE FASTENER CARTRIDGE COMPRISING A SUPPORT RETAINER, now U.S. Patent Application Publication No. 2012/0080344;

[0214] U.S. patent application Ser. No. 12/894,312, entitled IMPLANTABLE FASTENER CARTRIDGE COMPRISING MULTIPLE LAYERS, now U.S. Pat. No. 8,925,782;

[0215] U.S. patent application Ser. No. 12/894,377, entitled SELECTIVELY ORIENTABLE IMPLANTABLE FASTENER CARTRIDGE, now U.S. Pat. No. 8,393,514;

[0216] U.S. patent application Ser. No. 12/894,339, entitled SURGICAL STAPLING INSTRUMENT WITH COMPACT ARTICULATION CONTROL ARRANGEMENT, now U.S. Pat. No. 8,840,003;

[0217] U.S. patent application Ser. No. 12/894,360, entitled SURGICAL STAPLING INSTRUMENT WITH A VARIABLE STAPLE FORMING SYSTEM, now U.S. Pat. No. 9,113,862;

[0218] U.S. patent application Ser. No. 12/894,322, entitled SURGICAL STAPLING INSTRUMENT WITH INTERCHANGEABLE STAPLE CARTRIDGE ARRANGEMENTS, now U.S. Pat. No. 8,740,034;

[0219] U.S. patent application Ser. No. 12/894,350, entitled SURGICAL STAPLE CARTRIDGES WITH DETACHABLE SUPPORT STRUCTURES AND SURGICAL STAPLING INSTRUMENTS WITH SYSTEMS FOR PREVENTING ACTUATION MOTIONS WHEN A CARTRIDGE IS NOT PRESENT, now U.S. Patent Application Publication No. 2012/0080478;

[0220] U.S. patent application Ser. No. 12/894,383, entitled IMPLANTABLE FASTENER CARTRIDGE COMPRISING BIOABSORBABLE LAYERS, now U.S. Pat. No. 8,752,699;

[0221] U.S. patent application Ser. No. 12/894,389, entitled COMPRESSIBLE FASTENER CARTRIDGE, now U.S. Pat. No. 8,740,037;

[0222] U.S. patent application Ser. No. 12/894,345, entitled FASTENERS SUPPORTED BY A FASTENER CARTRIDGE SUPPORT, now U.S. Pat. No. 8,783,542;

[0223] U.S. patent application Ser. No. 12/894,306, entitled COLLAPSIBLE FASTENER CARTRIDGE, now U.S. Pat. No. 9,044,227;

[0224] U.S. patent application Ser. No. 12/894,318, entitled FASTENER SYSTEM COMPRISING A PLURALITY OF CONNECTED RETENTION MATRIX ELEMENTS, now U.S. Pat. No. 8,814,024;

[0225] U.S. patent application Ser. No. 12/894,330, entitled FASTENER SYSTEM COMPRISING A RETENTION MATRIX AND AN ALIGNMENT MATRIX, now U.S. Pat. No. 8,757,465;

[0226] U.S. patent application Ser. No. 12/894,361, entitled FASTENER SYSTEM COMPRISING A RETENTION MATRIX, now U.S. Pat. No. 8,529,600;

[0227] U.S. patent application Ser. No. 12/894,367, entitled FASTENING INSTRUMENT FOR DEPLOYING A FASTENER SYSTEM COMPRISING A RETENTION MATRIX, now U.S. Pat. No. 9,033,203;

[0228] U.S. patent application Ser. No. 12/894,388, entitled FASTENER SYSTEM COMPRISING A RETENTION MATRIX AND A COVER, now U.S. Pat. No. 8,474,677;

[0229] U.S. patent application Ser. No. 12/894,376, entitled FASTENER SYSTEM COMPRISING A PLURALITY OF FASTENER CARTRIDGES, now U.S. Pat. No. 9,044,228;

[0230] U.S. patent application Ser. No. 13/097,865, entitled SURGICAL STAPLER ANVIL COMPRISING A PLURALITY OF FORMING POCKETS, now U.S. Patent Application Publication No. 2012/0080488;

[0231] U.S. patent application Ser. No. 13/097,936, entitled TISSUE THICKNESS COMPENSATOR FOR A SURGICAL STAPLER, now U.S. Pat. No. 8,657,176;

[0232] U.S. patent application Ser. No. 13/097,954, entitled STAPLE CARTRIDGE COMPRISING A VARIABLE THICKNESS COMPRESSIBLE PORTION, now U.S. Patent Application Publication No. 2012/0080340;

[0233] U.S. patent application Ser. No. 13/097,856, entitled STAPLE CARTRIDGE COMPRISING STAPLES POSITIONED WITHIN A COMPRESSIBLE PORTION THEREOF, now U.S. Patent Application Publication No. 2012/0080336;

[0234] U.S. patent application Ser. No. 13/097,928, entitled TISSUE THICKNESS COMPENSATOR COMPRISING DETACHABLE PORTIONS, now U.S. Pat. No. 8,746,535;

[0235] U.S. patent application Ser. No. 13/097,891, entitled TISSUE THICKNESS COMPENSATOR FOR A SURGICAL STAPLER COMPRISING AN ADJUSTABLE ANVIL, now U.S. Pat. No. 8,864,009;

[0236] U.S. patent application Ser. No. 13/097,948, entitled STAPLE CARTRIDGE COMPRISING AN ADJUSTABLE DISTAL PORTION, now U.S. Pat. No. 8,978,954;

[0237] U.S. patent application Ser. No. 13/097,907, entitled COMPRESSIBLE STAPLE CARTRIDGE ASSEMBLY, now U.S. Patent Application Publication No. 2012/0080338;

[0238] U.S. patent application Ser. No. 13/097,861, entitled TISSUE THICKNESS COMPENSATOR COMPRISING PORTIONS HAVING DIFFERENT PROPERTIES, now U.S. Pat. No. 9,113,865;

[0239] U.S. patent application Ser. No. 13/097,869, entitled STAPLE CARTRIDGE LOADING ASSEMBLY, now U.S. Pat. No. 8,857,694;

[0240] U.S. patent application Ser. No. 13/097,917, entitled COMPRESSIBLE STAPLE CARTRIDGE COMPRISING ALIGNMENT MEMBERS, now U.S. Pat. No. 8,777,004;

[0241] U.S. patent application Ser. No. 13/097,873, entitled STAPLE CARTRIDGE COMPRISING A RELEASABLE PORTION, now U.S. Pat. No. 8,740,038;

[0242] U.S. patent application Ser. No. 13/097,938, entitled STAPLE CARTRIDGE COMPRISING COMPRESSIBLE DISTORTION RESISTANT COMPONENTS, now U.S. Pat. No. 9,016,542;

[0243] U.S. patent application Ser. No. 13/097,924, entitled STAPLE CARTRIDGE COMPRISING A TISSUE THICKNESS COMPENSATOR, now U.S. Pat. No. 9,168,038;

• [0244] U.S. patent application Ser. No. 13/242,029, entitled SURGICAL STAPLER WITH FLOATING ANVIL, now U.S. Pat. No. 8,893,949;

[0245] U.S. patent application Ser. No. 13/242,066, entitled CURVED END EFFECTOR FOR A STAPLING INSTRUMENT, now U.S. Patent Application Publication No. 2012/0080498;

[0246] U.S. patent application Ser. No. 13/242,086, entitled STAPLE CARTRIDGE INCLUDING COLLAPSIBLE DECK, now U.S. Pat. No. 9,055,941;

[0247] U.S. patent application Ser. No. 13/241,912, entitled STAPLE CARTRIDGE INCLUDING COLLAPSIBLE DECK ARRANGEMENT, now U.S. Pat. No. 9,050,084;

[0248] U.S. patent application Ser. No. 13/241,922, entitled SURGICAL STAPLER WITH STATIONARY STAPLE DRIVERS, now U.S. Pat. No. 9,216,019;

[0249] U.S. patent application Ser. No. 13/241,637, entitled SURGICAL INSTRUMENT WITH TRIGGER ASSEMBLY FOR GENERATING MULTIPLE ACTUATION MOTIONS, now U.S. Pat. No. 8,789,741; and

[0250] U.S. patent application Ser. No. 13/241,629, entitled SURGICAL INSTRUMENT WITH SELECTIVELY ARTICULATABLE END EFFECTOR, now U.S. Patent Application Publication No. 2012/0074200.

[0251] The Applicant of the present application also owns the U.S. Patent Applications identified below which were filed on Mar. 28, 2012 and which are each herein incorporated by reference in their respective entirety:

[0252] U.S. patent application Ser. No. 13/433,096, entitled TISSUE THICKNESS COMPENSATOR COMPRISING A PLURALITY OF CAPSULES, now U.S. Patent Application Publication No. 2012/0241496;

[0253] U.S. patent application Ser. No. 13/433,103, entitled TISSUE THICKNESS COMPENSATOR COMPRISING A PLURALITY OF LAYERS, now U.S. Patent Application Publication No. 2012/0241498;

[0254] U.S. patent application Ser. No. 13/433,098, entitled EXPANDABLE TISSUE THICKNESS COMPENSATOR, now U.S. Patent Application Publication No. 2012/0241491;

[0255] U.S. patent application Ser. No. 13/433,102, entitled TISSUE THICKNESS COMPENSATOR COMPRISING A RESERVOIR, now U.S. Pat. No. 9,232,241;

[0256] U.S. patent application Ser. No. 13/433,114, entitled RETAINER ASSEMBLY INCLUDING A TISSUE THICKNESS COMPENSATOR, now U.S. Patent Application Publication No. 2012/0241499;

[0257] U.S. patent application Ser. No. 13/433,136, entitled TISSUE THICKNESS COMPENSATOR COMPRISING AT LEAST ONE MEDICAMENT, now U.S. Patent Application Publication No. 2012/0241492;

[0258] U.S. patent application Ser. No. 13/433,141, entitled TISSUE THICKNESS COMPENSATOR COMPRISING CONTROLLED RELEASE AND EXPANSION, now U.S. Patent Application Publication No. 2012/0241493;

[0259] U.S. patent application Ser. No. 13/433,144, entitled TISSUE THICKNESS COMPENSATOR COMPRISING FIBERS TO PRODUCE A RESILIENT LOAD, now U.S. Pat. No. 9,277,919;

[0260] U.S. patent application Ser. No. 13/433,148, entitled TISSUE THICKNESS COMPENSATOR COMPRISING STRUCTURE TO PRODUCE A RESILIENT LOAD, now U.S. Pat. No. 9,220,500;

[0261] U.S. patent application Ser. No. 13/433,155, entitled TISSUE THICKNESS COMPENSATOR COMPRISING RESILIENT MEMBERS, now U.S. Patent Application Publication No. 2012/0241502;

[0262] U.S. patent application Ser. No. 13/433,163, entitled METHODS FOR FORMING TISSUE THICKNESS COMPENSATOR ARRANGEMENTS FOR SURGICAL STAPLERS, now U.S. Patent Application Publication No. 2012/0248169;

[0263] U.S. patent application Ser. No. 13/433,167, entitled TISSUE THICKNESS COMPENSATORS, now U.S. Pat. No. 9,220,501;

[0264] U.S. patent application Ser. No. 13/433,175, entitled LAYERED TISSUE THICKNESS COMPENSATOR, now U.S. Patent Application Publication No. 2012/0253298;

[0265] U.S. patent application Ser. No. 13/433,179, entitled TISSUE THICKNESS COMPENSATORS FOR CIRCULAR SURGICAL STAPLERS, now U.S. Patent Application Publication No. 2012/0241505;

[0266] U.S. patent application Ser. No. 13/433,115, entitled TISSUE THICKNESS COMPENSATOR COMPRISING CAPSULES DEFINING A LOW PRESSURE ENVIRONMENT, now U.S. Pat. No. 9,204,880;

[0267] U.S. patent application Ser. No. 13/433,135, entitled MOVABLE MEMBER FOR USE WITH A TISSUE THICKNESS COMPENSATOR, now U.S. Patent Application Publication No. 2013/0256382;

[0268] U.S. patent application Ser. No. 13/433,129, entitled TISSUE THICKNESS COMPENSATOR COMPRISING A PLURALITY OF MEDICAMENTS, now U.S. Pat. No. 9,211,120;

[0269] U.S. patent application Ser. No. 13/433,140, entitled TISSUE THICKNESS COMPENSATOR AND METHOD FOR MAKING THE SAME, now U.S. Pat. No. 9,241,714;

[0270] U.S. patent application Ser. No. 13/433,147, entitled TISSUE THICKNESS COMPENSATOR COMPRISING CHANNELS, now U.S. Patent Application Publication No. 2013/0256369;

[0271] U.S. patent application Ser. No. 13/433,126, entitled TISSUE THICKNESS COMPENSATOR COMPRISING TISSUE INGROWTH FEATURES, now U.S. Patent Application Publication No. 2013/0256366; and

[0272] U.S. patent application Ser. No. 13/433,132, entitled DEVICES AND METHODS FOR ATTACHING TISSUE THICKNESS COMPENSATING MATERIALS TO SURGICAL STAPLING INSTRUMENTS, now U.S. Patent Application Publication No. 2013/0256373.

[0273] Certain exemplary embodiments will now be described to provide an overall understanding of the principles of the structure, function, manufacture, and use of the devices and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the various embodiments of the present invention is defined solely by the claims. The features illustrated or described in connection with one exemplary embodiment may be combined with the features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention.

[0274] Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment”, or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment”, or “in an embodiment”, or the like, in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined, in whole or in part, with the features structures, or characteristics of one or more other embodiments without limitation. Such modifications and variations are intended to be included within the scope of the present invention.

[0275] The terms “proximal” and “distal” are used herein with reference to a clinician manipulating the handle portion of the surgical instrument. The term “proximal” referring to the portion closest to the clinician and the term “distal” referring to the portion located away from the clinician. It will be further appreciated that, for convenience and clarity, spatial terms such as “vertical”, “horizontal”, “up”, and “down” may be used herein with respect to the drawings. However, surgical instruments are used in many orientations and positions, and these terms are not intended to be limiting and/or absolute.

[0276] Various exemplary devices and methods are provided for performing laparoscopic and minimally invasive surgical procedures. However, the person of ordinary skill in the art will readily appreciate that the various methods and devices disclosed herein can be used in numerous surgical procedures and applications including, for example, in connection with open surgical procedures. As the present Detailed Description proceeds, those of ordinary skill in the art will further appreciate that the various instruments disclosed herein can be inserted into a body in any way, such as through a natural orifice, through an incision or puncture hole formed in tissue, etc. The working portions or end effector portions of the instruments can be inserted directly into a patient's body or can be inserted through an access device that has a working channel through which the end effector and elongated shaft of a surgical instrument can be advanced.

[0277] Turning to the Drawings wherein like numerals denote like components throughout the several views, FIG. 1 depicts a surgical instrument 10 that is capable of practicing several unique benefits. The surgical stapling instrument 10 is designed to manipulate and/or actuate various forms and sizes of end effectors 12 that are operably attached thereto. In the embodiment depicted in FIGS. 1-1E, for example, the end effector 12 includes an elongated channel 14 that forms a lower jaw 13 of the end effector 12. The elongated channel 14 is configured to support an “implantable” staple cartridge 30 and also movably support an anvil 20 that functions as an upper jaw 15 of the end effector 12.

[0278] In various embodiments, the elongated channel 14 may be fabricated from, for example, 300 & 400 Series, 17-4 & 17-7 stainless steel, titanium, etc. and be formed with spaced side walls 16. The anvil 20 may be fabricated from, for example, 300 & 400 Series, 17-4 & 17-7 stainless steel, titanium, etc. and have a staple forming undersurface, generally labeled as 22 that has a plurality of staple forming pockets 23 formed therein. See FIGS. 1B-1E. In addition, the anvil 20 has a bifurcated ramp assembly 24 that protrudes proximally therefrom. An anvil pin 26 protrudes from each lateral side of the ramp assembly 24 to be received within a corresponding slot or opening 18 in the side walls 16 of the elongated channel 14 to facilitate its movable or pivotable attachment thereto.

[0279] Various forms of implantable staple cartridges may be employed with the various embodiments of the surgical instruments disclosed herein. Specific staple cartridge configurations and constructions will be discussed in further detail below. However, in the embodiment depicted in FIG. 1A, an implantable staple cartridge 30 is shown. In at least one embodiment, the staple cartridge 30 has a body portion 31 that consists of a compressible hemostat material such as, for example, oxidized regenerated cellulose (“ORC”) or a bioabsorbable foam in which lines of unformed metal staples 32 are supported. In at least some embodiments, in order to prevent the staple from being affected and the hemostat material from being activated during the introduction and positioning process, the entire cartridge may be coated or wrapped in a biodegradable film 38 such as a polydioxanon film sold under the trademark PDS® or with a Polyglycerol sebacate (PGS) film or other biodegradable films formed from PGA (Polyglycolic acid, marketed under the trade mark Vicryl), PCL (Polycaprolactone), PLA or PLLA (Polylactic acid), PHA (polyhydroxyalkanoate), PGCL (poliglecaprone 25, sold under the trademark Monocryl) or a composite of PGA, PCL, PLA, PDS that would be impermeable until ruptured. The body 31 of staple cartridge 30 is sized to be removably supported within the elongated channel 14 as shown such that each staple 32 therein is aligned with corresponding staple forming pockets 23 in the anvil when the anvil 20 is driven into forming contact with the staple cartridge 30.

[0280] In use, once the end effector 12 has been positioned adjacent the target tissue, the end effector 12 is manipulated to capture or clamp the target tissue between an upper face 36 of the staple cartridge 30 and the staple forming surface 22 of the anvil 20. The staples 32 are formed by moving the anvil 20 in a path that is substantially parallel to the elongated channel 14 to bring the staple forming surface 22 and, more particularly, the staple forming pockets 23 therein into substantially simultaneous contact with the upper face 36 of the staple cartridge 30. As the anvil 20 continues to move into the staple cartridge 30, the legs 34 of the staples 32 contact a corresponding staple forming pocket 23 in anvil 20 which serves to bend the staple legs 34 over to form the staples 32 into a “B shape”. Further movement of the anvil 20 toward the elongated channel 14 will further compress and form the staples 32 to a desired final formed height “FF”.

[0281] The above-described staple forming process is generally depicted in FIGS. 1B-1E. For example, FIG. 1B illustrates the end effector 12 with target tissue “T” between the anvil 20 and the upper face 36 of the implantable staple cartridge 30. FIG. 1C illustrates the initial clamping position of the anvil 20 wherein the anvil has 20 been closed onto the target tissue “T” to clamp the target tissue “T” between the anvil 20 and the upper face 36 of the staple cartridge 30. FIG. 1D illustrates the initial staple formation wherein the anvil 20 has started to compress the staple cartridge 30 such that the legs 34 of the staples 32 are starting to be formed by the staple forming pockets 23 in the anvil 20. FIG. 1E illustrates the staple 32 in its final formed condition through the target tissue “T” with the anvil 20 removed for clarity purposes. Once the staples 32 have been formed and fastened to the target tissue “T”, the surgeon will move the anvil 20 to the open position to enable the cartridge body 31 and the staples 32 to remain affixed to the target tissue while the end effector 12 is being withdrawn from the patient. The end effector 12 forms all of the staples simultaneously as the two jaws 13, 15 are clamped together. The remaining “crushed” body materials 31 act as both a hemostat (the ORC) and a staple line reinforcement (PGA, PDS or any of the other film compositions mentioned above 38). Also, since the staples 32 never have to leave the cartridge body 31 during forming, the likelihood of the staples 32 being malformed during forming is minimized. As used herein the term “implantable” means that, in addition to the staples, the cartridge body materials that support the staples will also remain in the patient and may eventually be absorbed by the patient's body. Such implantable staple cartridges are distinguishable from prior cartridge arrangements that remain positioned within the end effector in their entirety after they have been fired.

[0282] In various implementations, the end effector 12 is configured to be coupled to an elongated shaft assembly 40 that protrudes from a handle assembly 100. The end effector 12 (when closed) and the elongated shaft assembly 40 may have similar cross-sectional shapes and be sized to operably pass through a trocar tube or working channel in another form of access instrument. As used herein, the term “operably pass” means that the end effector and at least a portion of the elongated shaft assembly may be inserted through or passed through the channel or tube opening and can be manipulated therein as needed to complete the surgical stapling procedure. In some embodiments, when in a closed position, the jaws 13 and 15 of the end effector 12 may provide the end effector with a roughly circular cross-sectional shape that facilitates its passage through a circular passage/opening. However, the end effectors of various embodiments of the present invention, as well as the elongated shaft assembly embodiments, could conceivably be provided with other cross-sectional shapes that could otherwise pass through access passages and openings that have non-circular cross-sectional shapes. Thus, an overall size of a cross-section of a closed end effector will be related to the size of the passage or opening through which it is intended to pass. Thus, one end effector for example, may be referred to as a “5 mm” end effector which means it can operably pass through an opening that is at least approximately 5 mm in diameter.

[0283] In various embodiments, the elongated shaft assembly 40 may have an outer diameter that is substantially the same as the outer diameter of the end effector 12 when in a closed position. For example, a 5 mm end effector may be coupled to an elongated shaft assembly 40 that has 5 mm cross-sectional diameter. However, as the present Detailed Description proceeds, it will become apparent that various embodiments of the present may be effectively used in connection with different sizes of end effectors. For example, a 10 mm end effector may be attached to an elongated shaft that has a 5 mm cross-sectional diameter. Conversely, for those applications wherein a 10 mm or larger access opening or passage is provided, the elongated shaft assembly 40 may have a 10 mm (or larger) cross-sectional diameter, but may also be able to actuate a 5 mm or 10 mm end effector. Accordingly, the outer shaft 40 may have an outer diameter that is the same as or is different from the outer diameter of a closed end effector 12 attached thereto.

[0284] As depicted, the elongated shaft assembly 40 extends distally from the handle assembly 100 in a generally straight line to define a longitudinal axis A-A. In various embodiments, for example, the elongated shaft assembly 40 may be approximately 9-16 inches (229-406 mm) long. However, the elongated shaft assembly 40 may be provided in other lengths and, in other embodiments, may have joints therein or be otherwise configured to facilitate articulation of the end effector 12 relative to other portions of the shaft or handle assembly as will be discussed in further detail below. In various embodiments, the elongated shaft assembly 40 includes a spine member 50 that extends from the handle assembly 100 to the end effector 12. The proximal end of the elongated channel 14 of the end effector 12 has a pair of retention trunnions 17 protruding therefrom that are sized to be received within corresponding trunnion openings or cradles 52 that are provided in a distal end of the spine member 50 to enable the end effector 12 to be removably coupled the elongated shaft assembly 40. The spine member 50 may be fabricated from, for example, 6061 or 7075 aluminum, stainless steel, titanium, etc.

[0285] In various embodiments, the handle assembly 100 comprises a pistol grip-type housing that may be fabricated in two or more pieces for assembly purposes. For example, the handle assembly 100 as shown comprises a right hand case member 102 and a left hand case member (not illustrated) that are molded or otherwise fabricated from a polymer or plastic material and are designed to mate together. Such case members may be attached together by snap features, pegs and sockets molded or otherwise formed therein and/or by adhesive, screws, etc. The spine member 50 has a proximal end 54 that has a flange 56 formed thereon. The flange 56 is configured to be rotatably supported within a groove 106 formed by mating ribs 108 that protrude inwardly from each of the case members 102, 104. Such arrangement facilitates the attachment of the spine member 50 to the handle assembly 100 while enabling the spine member 50 to be rotated relative to the handle assembly 100 about the longitudinal axis A-A in a 360° path.

[0286] As can be further seen in FIG. 1, the spine member 50 passes through and is supported by a mounting bushing 60 that is rotatably affixed to the handle assembly 100. The mounting bushing 60 has a proximal flange 62 and a distal flange 64 that define a rotational groove 65 that is configured to rotatably receive a nose portion 101 of the handle assembly 100 therebetween. Such arrangement enables the mounting bushing 60 to rotate about longitudinal axis A-A relative to the handle assembly 100. The spine member 50 is non-rotatably pinned to the mounting bushing 60 by a spine pin 66. In addition, a rotation knob 70 is attached to the mounting bushing 60. In one embodiment, for example, the rotation knob 70 has a hollow mounting flange portion 72 that is sized to receive a portion of the mounting bushing 60 therein. In various embodiments, the rotation knob 70 may be fabricated from, for example, glass or carbon filled Nylon, polycarbonate, Ultem®, etc. and is affixed to the mounting bushing 60 by the spine pin 66 as well. In addition, an inwardly protruding retention flange 74 is formed on the mounting flange portion 72 and is configured to extend into a radial groove 68 formed in the mounting bushing 60. Thus, the surgeon may rotate the spine member 50 (and the end effector 12 attached thereto) about longitudinal axis A-A in a 360° path by grasping the rotation knob 70 and rotating it relative to the handle assembly 100.

[0287] In various embodiments, the anvil 20 is retained in an open position by an anvil spring 21 and/or another biasing arrangement. The anvil 20 is selectively movable from the open position to various closed or clamping and firing positions by a firing system, generally designated as 109. The firing system 109 includes a “firing member” 110 which, in various embodiments, comprises a hollow firing tube 110. The hollow firing tube 110 is axially movable on the spine member 50 and thus forms the outer portion of the elongated shaft assembly 40. The firing tube 110 may be fabricated from a polymer or other suitable material and have a proximal end that is attached to a firing yoke 114 of the firing system 109. In various embodiments for example, the firing yoke 114 may be over-molded to the proximal end of the firing tube 110. However, other fastener arrangements may be employed.

[0288] As can be seen in FIG. 1, the firing yoke 114 may be rotatably supported within a support collar 120 that is configured to move axially within the handle assembly 100. In various embodiments, the support collar 120 has a pair of laterally extending fins that are sized to be slidably received within fin slots formed in the right and left hand case members. Thus, the support collar 120 may slide axially within the handle housing 100 while enabling the firing yoke 114 and firing tube 110 to rotate relative thereto about the longitudinal axis A-A. In various embodiments, a longitudinal slot is provided through the firing tube 110 to enable the spine pin 66 to extend therethrough into the spine member 50 while facilitating the axial travel of the firing tube 110 on the spine member 50.

[0289] The firing system 109 further comprises a firing trigger 130 which serves to control the axial travel of the firing tube 110 on the spine member 50. See FIG. 1. Such axial movement in the distal direction of the firing tube 110 into firing interaction with the anvil 20 is referred to herein as “firing motion”. As can be seen in FIG. 1, the firing trigger 130 is movably or pivotally coupled to the handle assembly 100 by a pivot pin 132. A torsion spring 135 is employed to bias the firing trigger 130 away from the pistol grip portion 107 of the handle assembly 100 to an un-actuated “open” or starting position. As can be seen in FIG. 1, the firing trigger 130 has an upper portion 134 that is movably attached to (pinned) firing links 136 that are movably attached to (pinned) the support collar 120. Thus, movement of the firing trigger 130 from the starting position (FIG. 1) toward an ending position adjacent the pistol grip portion 107 of the handle assembly 100 will cause the firing yoke 114 and the firing tube 110 to move in the distal direction “DD”. Movement of the firing trigger 130 away from the pistol grip portion 107 of the handle assembly 100 (under the bias of the torsion spring 135) will cause the firing yoke 114 and firing tube 110 to move in the proximal direction “PD” on the spine member 50.

[0290] Various embodiments of the present invention may be employed with different sizes and configurations of implantable staple cartridges. For example, the surgical instrument 10, when used in connection with a first firing adapter 140, may be used with a 5 mm end effector 12 that is approximately 20 mm long (or in other lengths) which supports an implantable staple cartridge 30. Such end effector size may be particularly well-suited, for example, to complete relatively fine dissection and vascular transactions. However, as will be discussed in further detail below, the surgical instrument 10 may also be employed, for example, in connection with other sizes of end effectors and staple cartridges by replacing the first firing adapter 140 with a second firing adapter. In still other embodiments, the elongated shaft assembly 40 may configured to be attached to only one form or size of end effector.

[0291] One method of removably coupling the end effector 12 to the spine member 50 will now be explained. The coupling process is commenced by inserting the retention trunnions 17 on the elongated channel 14 into the trunnion cradles 52 in the spine member 50. Thereafter, the surgeon advances the firing trigger 130 toward the pistol grip 107 of the housing assembly 100 to distally advance the firing tube 110 and the first firing adapter 140 over a proximal end portion 47 of the elongated channel 14 to thereby retain the trunnions 17 in their respective cradles 52. Such position of the first firing adapter 140 over the trunnions 17 is referred to herein as the “coupled position”. Various embodiments of the present invention may also have an end effector locking assembly for locking the firing trigger 130 in position after an end effector 12 has been attached to the spine member 50.

[0292] More specifically, one embodiment of the end effector locking assembly 160 includes a retention pin 162 that is movably supported in the upper portion 134 of the firing trigger 130. As discussed above, the firing tube 110 must initially be advanced distally to the coupled position wherein the first firing adapter 140 retains the retention trunnions 17 of the end effector 12 in the trunnion cradles 52 in the spine member 50. The surgeon advances the firing adapter 140 distally to the coupled position by pulling the firing trigger 130 from the starting position toward the pistol grip 107. As the firing trigger 130 is initially actuated, the retention pin 162 is moved distally until the firing tube 110 has advanced the first firing adapter 140 to the coupled position at which point the retention pin 162 is biased into a locking cavity 164 formed in the case member. In various embodiments, when the retention pin 162 enters into the locking cavity 164, the pin 162 may make an audible “click” or other sound, as well as provide a tactile indication to the surgeon that the end effector 12 has been “locked” onto the spine member 50. In addition, the surgeon cannot inadvertently continue to actuate the firing trigger 130 to start to form staples 32 in the end effector 12 without intentionally biasing the retention pin 162 out of the locking cavity 164. Similarly, if the surgeon releases the firing trigger 130 when in the coupled position, it is retained in that position by the retention pin 162 to prevent the firing trigger 130 from returning to the starting position and thereby releasing the end effector 12 from the spine member 50.

[0293] Various embodiments of the present invention may further include a firing system lock button 137 that is pivotally attached to the handle assembly 100. In one form, the firing system lock button 137 has a latch 138 formed on a distal end thereof that is oriented to engage the firing yoke 114 when the firing release button is in a first latching position. As can be seen in FIG. 1, a latch spring 139 serves to bias the firing system lock button 137 to the first latching position. In various circumstances, the latch 138 serves to engage the firing yoke 114 at a point where the position of the firing yoke 114 on the spine member 50 corresponds to a point wherein the first firing adapter 140 is about to distally advance up the clamping ramp 28 on the anvil 20. It will be understood that, as the first firing adapter 140 advances axially up the clamping ramp 28, the anvil 20 will move in a path such that its staple forming surface portion 22 is substantially parallel to the upper face 36 of the staple cartridge 30.

[0294] After the end effector 12 has been coupled to the spine member 50, the staple forming process is commenced by first depressing the firing system lock button 137 to enable the firing yoke 114 to be further moved distally on the spine member 50 and ultimately compress the anvil 20 into the staple cartridge 30. After depressing the firing system lock button 137, the surgeon continues to actuate the firing trigger 130 towards the pistol grip 107 thereby driving the first staple collar 140 up the corresponding staple forming ramp 29 to force the anvil 20 into forming contact with the staples 32 in the staple cartridge 30. The firing system lock button 137 prevents the inadvertent forming of the staples 32 until the surgeon is ready to start that process. In this embodiment, the surgeon must depress the firing system lock button 137 before the firing trigger 130 may be further actuated to begin the staple forming process.

[0295] The surgical instrument 10 may be solely used as a tissue stapling device if so desired. However, various embodiments of the present invention may also include a tissue cutting system, generally designated as 170. In at least one form, the tissue cutting system 170 comprises a knife member 172 that may be selectively advanced from an un-actuated position adjacent the proximal end of the end effector 12 to an actuated position by actuating a knife advancement trigger 200. The knife member 172 is movably supported within the spine member 50 and is attached or otherwise protrudes from a knife rod 180. The knife member 172 may be fabricated from, for example, 420 or 440 stainless steel with a hardness of greater than 38HRC (Rockwell Hardness C-scale) and have a tissue cutting edge 176 formed on the distal end 174 thereof and be configured to slidably extend through a slot in the anvil 20 and a centrally disposed slot 33 in the staple cartridge 30 to cut through tissue that is clamped in the end effector 12. In various embodiments, the knife rod 180 extends through the spine member 50 and has a proximal end portion which drivingly interfaces with a knife transmission that is operably attached to the knife advance trigger 200. In various embodiments, the knife advance trigger 200 is attached to pivot pin 132 such that it may be pivoted or otherwise actuated without actuating the firing trigger 130. In various embodiments, a first knife gear 192 is also attached to the pivot pin 132 such that actuation of the knife advance trigger 200 also pivots the first knife gear 192. A firing return spring 202 is attached between the first knife gear 192 and the handle housing 100 to bias the knife advancement trigger 200 to a starting or un-actuated position.

[0296] Various embodiments of the knife transmission also include a second knife gear 194 that is rotatably supported on a second gear spindle and in meshing engagement with the first knife gear 192. The second knife gear 194 is in meshing engagement with a third knife gear 196 that is supported on a third gear spindle. Also supported on the third gear spindle 195 is a fourth knife gear 198. The fourth knife gear 198 is adapted to drivingly engage a series of annular gear teeth or rings on a proximal end of the knife rod 180. Thus, such arrangement enables the fourth knife gear 198 to axially drive the knife rod 180 in the distal direction “DD” or proximal direction “PD” while enabling the firing rod 180 to rotate about longitudinal axis A-A with respect to the fourth knife gear 198. Accordingly, the surgeon may axially advance the firing rod 180 and ultimately the knife member 172 distally by pulling the knife advancement trigger 200 towards the pistol grip 107 of the handle assembly 100.

[0297] Various embodiments of the present invention further include a knife lockout system 210 that prevents the advancement of the knife member 172 unless the firing trigger 130 has been pulled to the fully fired position. Such feature will therefore prevent the activation of the knife advancement system 170 unless the staples have first been fired or formed into the tissue. As can be seen in FIG. 1, various implementations of the knife lockout system 210 comprise a knife lockout bar 211 that is pivotally supported within the pistol grip portion 107 of the handle assembly 100. The knife lockout bar 211 has an activation end 212 that is adapted to be engaged by the firing trigger 130 when the firing trigger 130 is in the fully fired position. In addition, the knife lockout bar 211 has a retaining hook 214 on its other end that is adapted to hookingly engage a latch rod 216 on the first cut gear 192. A knife lock spring 218 is employed to bias the knife lockout bar 211 to a “locked” position wherein the retaining hook 214 is retained in engagement with the latch rod 216 to thereby prevent actuation of the knife advancement trigger 200 unless the firing trigger 130 is in the fully fired position.

[0298] After the staples have been “fired” (formed) into the target tissue, the surgeon may depress the firing trigger release button 167 to enable the firing trigger 130 to return to the starting position under the bias of the torsion spring 135 which enables the anvil 20 to be biased to an open position under the bias of spring 21. When in the open position, the surgeon may withdraw the end effector 12 leaving the implantable staple cartridge 30 and staples 32 behind. In applications wherein the end effector was inserted through a passage, working channel, etc. the surgeon will return the anvil 20 to the closed position by activating the firing trigger 130 to enable the end effector 12 to be withdrawn out through the passage or working channel. If, however, the surgeon desires to cut the target tissue after firing the staples, the surgeon activates the knife advancement trigger 200 in the above-described manner to drive the knife bar 172 through the target tissue to the end of the end effector. Thereafter, the surgeon may release the knife advancement trigger 200 to enable the firing return spring 202 to cause the firing transmission to return the knife bar 172 to the starting (un-actuated) position. Once the knife bar 172 has been returned to the starting position, the surgeon may open the end effector jaws 13, 15 to release the implantable cartridge 30 within the patient and then withdraw the end effector 12 from the patient. Thus, such surgical instruments facilitate the use of small implantable staple cartridges that may be inserted through relatively smaller working channels and passages, while providing the surgeon with the option to fire the staples without cutting tissue or if desired to also cut tissue after the staples have been fired.

[0299] Various unique and novel embodiments of the present invention employ a compressible staple cartridge that supports staples in a substantially stationary position for forming contact by the anvil. In various embodiments, the anvil is driven into the unformed staples wherein, in at least one such embodiment, the degree of staple formation attained is dependent upon how far the anvil is driven into the staples. Such an arrangement provides the surgeon with the ability to adjust the amount of forming or firing pressure applied to the staples and thereby alter the final formed height of the staples. In other various embodiments of the present invention, surgical stapling arrangements can employ staple driving elements which can lift the staples toward the anvil. Such embodiments are described in greater detail further below.

[0300] In various embodiments, with regard to the embodiments described in detail above, the amount of firing motion that is applied to the movable anvil is dependent upon the degree of actuation of the firing trigger. For example, if the surgeon desires to attain only partially formed staples, then the firing trigger is only partially depressed inward towards the pistol grip 107. To attain more staple formation, the surgeon simply compresses the firing trigger further which results in the anvil being further driven into forming contact with the staples. As used herein, the term “forming contact” means that the staple forming surface or staple forming pockets have contacted the ends of the staple legs and have started to form or bend the legs over into a formed position. The degree of staple formation refers to how far the staple legs have been folded over and ultimately relates to the forming height of the staple as referenced above. Those of ordinary skill in the art will further understand that, because the anvil 20 moves in a substantially parallel relationship with respect to the staple cartridge as the firing motions are applied thereto, the staples are formed substantially simultaneously with substantially the same formed heights.

[0301] FIGS. 2 and 3 illustrate an alternative end effector 12″ that is similar to the end effector 12′ described above, except with the following differences that are configured to accommodate a knife bar 172′. The knife bar 172′ is coupled to or protrudes from a knife rod 180 and is otherwise operated in the above described manner with respect to the knife bar 172. However, in this embodiment, the knife bar 172′ is long enough to traverse the entire length of the end effector 12″ and therefore, a separate distal knife member is not employed in the end effector 12″. The knife bar 172′ has an upper transverse member 173′ and a lower transverse member 175′ formed thereon. The upper transverse member 173′ is oriented to slidably transverse a corresponding elongated slot 250 in anvil 20″ and the lower transverse member 175′ is oriented to traverse an elongated slot 252 in the elongated channel 14″ of the end effector 12″. A disengagement slot (not shown) is also provided in the anvil 20″ such that when the knife bar 172′ has been driven to an ending position within end effector 12″, the upper transverse member 173′ drops through the corresponding slot to enable the anvil 20″ to move to the open position to disengage the stapled and cut tissue. The anvil 20″ may be otherwise identical to anvil 20 described above and the elongated channel 14″ may be otherwise identical to elongated channel 14 described above.

[0302] In these embodiments, the anvil 20″ is biased to a fully open position (FIG. 2) by a spring or other opening arrangement (not shown). The anvil 20″ is moved between the open and fully clamped positions by the axial travel of the firing adapter 150 in the manner described above. Once the firing adapter 150 has been advanced to the fully clamped position (FIG. 3), the surgeon may then advance the knife bar 172″ distally in the manner described above. If the surgeon desires to use the end effector as a grasping device to manipulate tissue, the firing adapter may be moved proximally to allow the anvil 20″ to move away from the elongated channel 14″ as represented in FIG. 4 in broken lines. In this embodiment, as the knife bar 172″ moves distally, the upper transverse member 173′ and the lower transverse member 175′ draw the anvil 20″ and elongated channel 14″ together to achieve the desired staple formation as the knife bar 172″ is advanced distally through the end effector 12″. See FIG. 5. Thus, in this embodiment, staple formation occurs simultaneously with tissue cutting, but the staples themselves may be sequentially formed as the knife bar 172″ is driven distally.

[0303] The unique and novel features of the various surgical staple cartridges and the surgical instruments of the present invention enable the staples in those cartridges to be arranged in one or more linear or non-linear lines. A plurality of such staple lines may be provided on each side of an elongated slot that is centrally disposed within the staple cartridge for receiving the tissue cutting member therethrough. In one arrangement, for example, the staples in one line may be substantially parallel with the staples in adjacent line(s) of staples, but offset therefrom. In still other embodiments, one or more lines of staples may be non-linear in nature. That is, the base of at least one staple in a line of staples may extend along an axis that is substantially transverse to the bases of other staples in the same staple line. For example, the lines of staples on each side of the elongated slot may have a zigzag appearance.

[0304] In various embodiments, a staple cartridge can comprise a cartridge body and a plurality of staples stored within the cartridge body. In use, the staple cartridge can be introduced into a surgical site and positioned on a side of the tissue being treated. In addition, a staple-forming anvil can be positioned on the opposite side of the tissue. In various embodiments, the anvil can be carried by a first jaw and the staple cartridge can be carried by a second jaw, wherein the first jaw and/or the second jaw can be moved toward the other. Once the staple cartridge and the anvil have been positioned relative to the tissue, the staples can be ejected from the staple cartridge body such that the staples can pierce the tissue and contact the staple-forming anvil. Once the staples have been deployed from the staple cartridge body, the staple cartridge body can then be removed from the surgical site. In various embodiments disclosed herein, a staple cartridge, or at least a portion of a staple cartridge, can be implanted with the staples. In at least one such embodiment, as described in greater detail further below, a staple cartridge can comprise a cartridge body which can be compressed, crushed, and/or collapsed by the anvil when the anvil is moved from an open position into a closed position. When the cartridge body is compressed, crushed, and/or collapsed, the staples positioned within the cartridge body can be deformed by the anvil. Alternatively, the jaw supporting the staple cartridge can be moved toward the anvil into a closed position. In either event, in various embodiments, the staples can be deformed while they are at least partially positioned within the cartridge body. In certain embodiments, the staples may not be ejected from the staple cartridge while, in some embodiments, the staples can be ejected from the staple cartridge along with a portion of the cartridge body.

[0305] Referring now to FIGS. 6A-6D, a compressible staple cartridge, such as staple cartridge 1000, for example, can comprise a compressible, implantable cartridge body 1010 and, in addition, a plurality of staples 1020 positioned in the compressible cartridge body 1010, although only one staple 1020 is depicted in FIGS. 6A-6D. FIG. 6A illustrates the staple cartridge 1000 supported by a staple cartridge support, or staple cartridge channel, 1030, wherein the staple cartridge 1000 is illustrated in an uncompressed condition. In such an uncompressed condition, the anvil 1040 may or may not be in contact with the tissue T. In use, the anvil 1040 can be moved from an open position into contact with the tissue T as illustrated in FIG. 6B and position the tissue T against the cartridge body 1010. Even though the anvil 1040 can position the tissue T against a tissue-contacting surface 1019 of staple cartridge body 1010, referring again to FIG. 6B, the staple cartridge body 1010 may be subjected to little, if any, compressive force or pressure at such point and the staples 1020 may remain in an unformed, or unfired, condition. As illustrated in FIGS. 6A and 6B, the staple cartridge body 1010 can comprise one or more layers and the staple legs 1021 of staples 1020 can extend upwardly through these layers. In various embodiments, the cartridge body 1010 can comprise a first layer 1011, a second layer 1012, a third layer 1013, wherein the second layer 1012 can be positioned intermediate the first layer 1011 and the third layer 1013, and a fourth layer 1014, wherein the third layer 1013 can be positioned intermediate the second layer 1012 and the fourth layer 1014. In at least one embodiment, the bases 1022 of the staples 1020 can be positioned within cavities 1015 in the fourth layer 1014 and the staple legs 1021 can extend upwardly from the bases 1022 and through the fourth layer 1014, the third layer 1013, and the second layer 1012, for example. In various embodiments, each deformable leg 1021 can comprise a tip, such as sharp tip 1023, for example, which can be positioned in the second layer 1012, for example, when the staple cartridge 1000 is in an uncompressed condition. In at least one such embodiment, the tips 1023 may not extend into and/or through the first layer 1011, wherein, in at least one embodiment, the tips 1023 may not protrude through the tissue-contacting surface 1019 when the staple cartridge 1000 is in an uncompressed condition. In certain other embodiments, the sharp tips 1023 may be positioned in the third layer 1013, and/or any other suitable layer, when the staple cartridge is in an uncompressed condition. In various alternative embodiments, a cartridge body of a staple cartridge may have any suitable number of layers such as less than four layers or more than four layers, for example.

[0306] In various embodiments, as described in greater detail below, the first layer 1011 can be comprised of a buttress material and/or plastic material, such as polydioxanone (PDS) and/or polyglycolic acid (PGA), for example, and the second layer 1012 can be comprised of a bioabsorbable foam material and/or a compressible haemostatic material, such as oxidized regenerated cellulose (ORC), for example. In various embodiments, one or more of the first layer 1011, the second layer 1012, the third layer 1013, and the fourth layer 1014 may hold the staples 1020 within the staple cartridge body 1010 and, in addition, maintain the staples 1020 in alignment with one another. In various embodiments, the third layer 1013 can be comprised of a buttress material, or a fairly incompressible or inelastic material, which can be configured to hold the staple legs 1021 of the staples 1020 in position relative to one another. Furthermore, the second layer 1012 and the fourth layer 1014, which are positioned on opposite sides of the third layer 1013, can stabilize, or reduce the movement of, the staples 1020 even though the second layer 1012 and the fourth layer 1014 can be comprised of a compressible foam or elastic material. In certain embodiments, the staple tips 1023 of the staple legs 1021 can be at least partially embedded in the first layer 1011. In at least one such embodiment, the first layer 1011 and the third layer 1013 can be configured to co-operatively and firmly hold the staple legs 1021 in position. In at least one embodiment, the first layer 1011 and the third layer 1013 can each be comprised of a sheet of bioabsorbable plastic, such as polyglycolic acid (PGA) which is marketed under the trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example, and the second layer 1012 and the fourth layer 1014 can each be comprised of at least one haemostatic material or agent.

[0307] Although the first layer 1011 can be compressible, the second layer 1012 can be substantially more compressible than the first layer 1011. For example, the second layer 1012 can be about twice as compressible, about three times as compressible, about four times as compressible, about five times as compressible, and/or about ten times as compressible, for example, as the first layer 1011. Stated another way, the second layer 1012 may compress about two times, about three times, about four times, about five times, and/or about ten times as much as first layer 1011, for a given force. In certain embodiments, the second layer 1012 can be between about twice as compressible and about ten times as compressible, for example, as the first layer 1011. In at least one embodiment, the second layer 1012 can comprise a plurality of air voids defined therein, wherein the amount and/or size of the air voids in the second layer 1012 can be controlled in order to provide a desired compressibility of the second layer 1012. Similar to the above, although the third layer 1013 can be compressible, the fourth layer 1014 can be substantially more compressible than the third layer 1013. For example, the fourth layer 1014 can be about twice as compressible, about three times as compressible, about four times as compressible, about five times as compressible, and/or about ten times as compressible, for example, as the third layer 1013. Stated another way, the fourth layer 1014 may compress about two times, about three times, about four times, about five times, and/or about ten times as much as third layer 1013, for a given force. In certain embodiments, the fourth layer 1014 can be between about twice as compressible and about ten times as compressible, for example, as the third layer 1013. In at least one embodiment, the fourth layer 1014 can comprise a plurality of air voids defined therein, wherein the amount and/or size of the air voids in the fourth layer 1014 can be controlled in order to provide a desired compressibility of the fourth layer 1014. In various circumstances, the compressibility of a cartridge body, or cartridge body layer, can be expressed in terms of a compression rate, i.e., a distance in which a layer is compressed for a given amount of force. For example, a layer having a high compression rate will compress a larger distance for a given amount of compressive force applied to the layer as compared to a layer having a lower compression rate. This being said, the second layer 1012 can have a higher compression rate than the first layer 1011 and, similarly, the fourth layer 1014 can have a higher compression rate than the third layer 1013. In various embodiments, the second layer 1012 and the fourth layer 1014 can be comprised of the same material and can comprise the same compression rate. In various embodiments, the second layer 1012 and the fourth layer 1014 can be comprised of materials having different compression rates. Similarly, the first layer 1011 and the third layer 1013 can be comprised of the same material and can comprise the same compression rate. In certain embodiments, the first layer 1011 and the third layer 1013 can be comprised of materials having different compression rates.

[0308] As the anvil 1040 is moved toward its closed position, the anvil 1040 can contact tissue T and apply a compressive force to the tissue T and the staple cartridge 1000, as illustrated in FIG. 6C. In such circumstances, the anvil 1040 can push the top surface, or tissue-contacting surface 1019, of the cartridge body 1010 downwardly toward the staple cartridge support 1030. In various embodiments, the staple cartridge support 1030 can comprise a cartridge support surface 1031 which can be configured to support the staple cartridge 1000 as the staple cartridge 1000 is compressed between the cartridge support surface 1031 and the tissue-contacting surface 1041 of anvil 1040. Owing to the pressure applied by the anvil 1040, the cartridge body 1010 can be compressed and the anvil 1040 can come into contact with the staples 1020. More particularly, in various embodiments, the compression of the cartridge body 1010 and the downward movement of the tissue-contacting surface 1019 can cause the tips 1023 of the staple legs 1021 to pierce the first layer 1011 of cartridge body 1010, pierce the tissue T, and enter into forming pockets 1042 in the anvil 1040. As the cartridge body 1010 is further compressed by the anvil 1040, the tips 1023 can contact the walls defining the forming pockets 1042 and, as a result, the legs 1021 can be deformed or curled inwardly, for example, as illustrated in FIG. 6C. As the staple legs 1021 are being deformed, as also illustrated in FIG. 6C, the bases 1022 of the staples 1020 can be in contact with or supported by the staple cartridge support 1030. In various embodiments, as described in greater detail below, the staple cartridge support 1030 can comprise a plurality of support features, such as staple support grooves, slots, or troughs 1032, for example, which can be configured to support the staples 1020, or at least the bases 1022 of the staples 1020, as the staples 1020 are being deformed. As also illustrated in FIG. 6C, the cavities 1015 in the fourth layer 1014 can collapse as a result of the compressive force applied to the staple cartridge body 1010. In addition to the cavities 1015, the staple cartridge body 1010 can further comprise one or more voids, such as voids 1016, for example, which may or may not comprise a portion of a staple positioned therein, that can be configured to allow the cartridge body 1010 to collapse. In various embodiments, the cavities 1015 and/or the voids 1016 can be configured to collapse such that the walls defining the cavities and/or walls deflect downwardly and contact the cartridge support surface 1031 and/or contact a layer of the cartridge body 1010 positioned underneath the cavities and/or voids.

[0309] Upon comparing FIG. 6B and FIG. 6C, it is evident that the second layer 1012 and the fourth layer 1014 have been substantially compressed by the compressive pressure applied by the anvil 1040. It may also be noted that the first layer 1011 and the third layer 1013 have been compressed as well. As the anvil 1040 is moved into its closed position, the anvil 1040 may continue to further compress the cartridge body 1010 by pushing the tissue-contacting surface 1019 downwardly toward the staple cartridge support 1030. As the cartridge body 1010 is further compressed, the anvil 1040 can deform the staples 1020 into their completely-formed shape as illustrated in FIG. 6D. Referring to FIG. 6D, the legs 1021 of each staple 1020 can be deformed downwardly toward the base 1022 of each staple 1020 in order to capture at least a portion of the tissue T, the first layer 1011, the second layer 1012, the third layer 1013, and the fourth layer 1014 between the deformable legs 1021 and the base 1022. Upon comparing FIGS. 6C and 6D, it is further evident that the second layer 1012 and the fourth layer 1014 have been further substantially compressed by the compressive pressure applied by the anvil 1040. It may also be noted upon comparing FIGS. 6C and 6D that the first layer 1011 and the third layer 1013 have been further compressed as well. After the staples 1020 have been completely, or at least sufficiently, formed, the anvil 1040 can be lifted away from the tissue T and the staple cartridge support 1030 can be moved away, and/or detached from, the staple cartridge 1000. As depicted in FIG. 6D, and as a result of the above, the cartridge body 1010 can be implanted with the staples 1020. In various circumstances, the implanted cartridge body 1010 can support the tissue along the staple line. In some circumstances, a haemostatic agent, and/or any other suitable therapeutic medicament, contained within the implanted cartridge body 1010 can treat the tissue over time. A haemostatic agent, as mentioned above, can reduce the bleeding of the stapled and/or incised tissue while a bonding agent or tissue adhesive can provide strength to the tissue over time. The implanted cartridge body 1010 can be comprised of materials such as ORC (oxidized regenerated cellulose), extracellular proteins such as collagen, polyglycolic acid (PGA) which is marketed under the trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. In certain circumstances, the cartridge body 1010 can comprise an antibiotic and/or anti-microbial material, such as colloidal silver and/or triclosan, for example, which can reduce the possibility of infection in the surgical site.

[0310] In various embodiments, the layers of the cartridge body 1010 can be connected to one another. In at least one embodiment, the second layer 1012 can be adhered to the first layer 1011, the third layer 1013 can be adhered to the second layer 1012, and the fourth layer 1014 can be adhered to the third layer 1013 utilizing at least one adhesive, such as fibrin and/or protein hydrogel, for example. In certain embodiments, although not illustrated, the layers of the cartridge body 1010 can be connected together by interlocking mechanical features. In at least one such embodiment, the first layer 1011 and the second layer 1012 can each comprise corresponding interlocking features, such as a tongue and groove arrangement and/or a dovetail joint arrangement, for example. Similarly, the second layer 1012 and the third layer 1013 can each comprise corresponding interlocking features while the third layer 1013 and the fourth layer 1014 can each comprise corresponding interlocking features. In certain embodiments, although not illustrated, the staple cartridge 1000 can comprise one or more rivets, for example, which can extend through one or more layers of the cartridge body 1010. In at least one such embodiment, each rivet can comprise a first end, or head, positioned adjacent to the first layer 1011 and a second head positioned adjacent to the fourth layer 1014 which can be either assembled to or formed by a second end of the rivet. Owing to the compressible nature of the cartridge body 1010, in at least one embodiment, the rivets can compress the cartridge body 1010 such that the heads of the rivets can be recessed relative to the tissue-contacting surface 1019 and/or the bottom surface 1018 of the cartridge body 1010, for example. In at least one such embodiment, the rivets can be comprised of a bioabsorbable material, such as polyglycolic acid (PGA) which is marketed under the trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. In certain embodiments, the layers of the cartridge body 1010 may not be connected to one another other than by the staples 1020 contained therein. In at least one such embodiment, the frictional engagement between the staple legs 1021 and the cartridge body 1010, for example, can hold the layers of the cartridge body 1010 together and, once the staples have been formed, the layers can be captured within the staples 1020. In certain embodiments, at least a portion of the staple legs 1021 can comprise a roughened surface or rough coating which can increase the friction forces between the staples 1020 and the cartridge body 1010.

[0311] As described above, a surgical instrument can comprise a first jaw including the staple cartridge support 1030 and a second jaw including the anvil 1040. In various embodiments, as described in greater detail further below, the staple cartridge 1000 can comprise one or more retention features which can be configured to engage the staple cartridge support 1030 and, as a result, releasably retain the staple cartridge 1000 to the staple cartridge support 1030. In certain embodiments, the staple cartridge 1000 can be adhered to the staple cartridge support 1030 by at least one adhesive, such as fibrin and/or protein hydrogel, for example. In use, in at least one circumstance, especially in laparoscopic and/or endoscopic surgery, the second jaw can be moved into a closed position opposite the first jaw, for example, such that the first and second jaws can be inserted through a trocar into a surgical site. In at least one such embodiment, the trocar can define an approximately 5 mm aperture, or cannula, through which the first and second jaws can be inserted. In certain embodiments, the second jaw can be moved into a partially-closed position intermediate the open position and the closed position which can allow the first and second jaws to be inserted through the trocar without deforming the staples 1020 contained in the staple cartridge body 1010. In at least one such embodiment, the anvil 1040 may not apply a compressive force to the staple cartridge body 1010 when the second jaw is in its partially-closed intermediate position while, in certain other embodiments, the anvil 1040 can compress the staple cartridge body 1010 when the second jaw is in its partially-closed intermediate position. Even though the anvil 1040 can compress the staple cartridge body 1010 when it is in such an intermediate position, the anvil 1040 may not sufficiently compress the staple cartridge body 1010 such that the anvil 1040 comes into contact with the staples 1020 and/or such that the staples 1020 are deformed by the anvil 1040. Once the first and second jaws have been inserted through the trocar into the surgical site, the second jaw can be opened once again and the anvil 1040 and the staple cartridge 1000 can be positioned relative to the targeted tissue as described above.

[0312] In various embodiments, referring now to FIGS. 7A-7D, an end effector of a surgical stapler can comprise an implantable staple cartridge 1100 positioned intermediate an anvil 1140 and a staple cartridge support 1130. Similar to the above, the anvil 1140 can comprise a tissue-contacting surface 1141, the staple cartridge 1100 can comprise a tissue-contacting surface 1119, and the staple cartridge support 1130 can comprise a support surface 1131 which can be configured to support the staple cartridge 1100. Referring to FIG. 7A, the anvil 1140 can be utilized to position the tissue T against the tissue contacting surface 1119 of staple cartridge 1100 without deforming the staple cartridge 1100 and, when the anvil 1140 is in such a position, the tissue-contacting surface 1141 can be positioned a distance 1101a away from the staple cartridge support surface 1131 and the tissue-contacting surface 1119 can be positioned a distance 1102a away from the staple cartridge support surface 1131. Thereafter, as the anvil 1140 is moved toward the staple cartridge support 1130, referring now to FIG. 7B, the anvil 1140 can push the top surface, or tissue-contacting surface 1119, of staple cartridge 1100 downwardly and compress the first layer 1111 and the second layer 1112 of cartridge body 1110. As the layers 1111 and 1112 are compressed, referring again to FIG. 7B, the second layer 1112 can be crushed and the legs 1121 of staples 1120 can pierce the first layer 1111 and enter into the tissue T. In at least one such embodiment, the staples 1120 can be at least partially positioned within staple cavities, or voids, 1115 in the second layer 1112 and, when the second layer 1112 is compressed, the staple cavities 1115 can collapse and, as a result, allow the second layer 1112 to collapse around the staples 1120. In various embodiments, the second layer 1112 can comprise cover portions 1116 which can extend over the staple cavities 1115 and enclose, or at least partially enclose, the staple cavities 1115. FIG. 7B illustrates the cover portions 1116 being crushed downwardly into the staple cavities 1115. In certain embodiments, the second layer 1112 can comprise one or more weakened portions which can facilitate the collapse of the second layer 1112. In various embodiments, such weakened portions can comprise score marks, perforations, and/or thin cross-sections, for example, which can facilitate a controlled collapse of the cartridge body 1110. In at least one embodiment, the first layer 1111 can comprise one or more weakened portions which can facilitate the penetration of the staple legs 1121 through the first layer 1111. In various embodiments, such weakened portions can comprise score marks, perforations, and/or thin cross-sections, for example, which can be aligned, or at least substantially aligned, with the staple legs 1121.

[0313] When the anvil 1140 is in a partially closed, unfired position, referring again to FIG. 7A, the anvil 1140 can be positioned a distance 1101a away from the cartridge support surface 1131 such that a gap is defined therebetween. This gap can be filled by the staple cartridge 1100, having a staple cartridge height 1102a, and the tissue T. As the anvil 1140 is moved downwardly to compress the staple cartridge 1100, referring again to FIG. 7B, the distance between the tissue contacting surface 1141 and the cartridge support surface 1131 can be defined by a distance 1101b which is shorter than the distance 1101a. In various circumstances, the gap between the tissue-contacting surface 1141 of anvil 1140 and the cartridge support surface 1131, defined by distance 1101b, may be larger than the original, undeformed staple cartridge height 1102a. As the anvil 1140 is moved closer to the cartridge support surface 1131, referring now to FIG. 7C, the second layer 1112 can continue to collapse and the distance between the staple legs 1121 and the forming pockets 1142 can decrease. Similarly, the distance between the tissue-contacting surface 1141 and the cartridge support surface 1131 can decrease to a distance 1101c which, in various embodiments, may be greater than, equal to, or less than the original, undeformed cartridge height 1102a. Referring now to FIG. 7D, the anvil 1140 can be moved into a final, fired position in which the staples 1120 have been fully formed, or at least formed to a desired height. In such a position, the tissue-contacting surface 1141 of anvil 1140 can be a distance 1101d away from the cartridge support surface 1131, wherein the distance 1101d can be shorter than the original, undeformed cartridge height 1102a. As also illustrated in FIG. 7D, the staple cavities 1115 may be fully, or at least substantially, collapsed and the staples 1120 may be completely, or at least substantially, surrounded by the collapsed second layer 1112. In various circumstances, the anvil 1140 can be thereafter moved away from the staple cartridge 1100. Once the anvil 1140 has been disengaged from the staple cartridge 1100, the cartridge body 1110 can at least partially re-expand in various locations, i.e., locations intermediate adjacent staples 1120, for example. In at least one embodiment, the crushed cartridge body 1110 may not resiliently re-expand. In various embodiments, the formed staples 1120 and, in addition, the cartridge body 1110 positioned intermediate adjacent staples 1120 may apply pressure, or compressive forces, to the tissue T which may provide various therapeutic benefits.

[0314] As discussed above, referring again to the embodiment illustrated in FIG. 7A, each staple 1120 can comprise staple legs 1121 extending therefrom. Although staples 1120 are depicted as comprising two staple legs 1121, various staples can be utilized which can comprise one staple leg or, alternatively, more than two staple legs, such as three staple legs or four staple legs, for example. As illustrated in FIG. 7A, each staple leg 1121 can be embedded in the second layer 1112 of the cartridge body 1110 such that the staples 1120 are secured within the second layer 1112. In various embodiments, the staples 1120 can be inserted into the staple cavities 1115 in cartridge body 1110 such that the tips 1123 of the staple legs 1121 enter into the cavities 1115 before the bases 1122. After the tips 1123 have been inserted into the cavities 1115, in various embodiments, the tips 1123 can be pressed into the cover portions 1116 and incise the second layer 1112. In various embodiments, the staples 1120 can be seated to a sufficient depth within the second layer 1112 such that the staples 1120 do not move, or at least substantially move, relative to the second layer 1112. In certain embodiments, the staples 1120 can be seated to a sufficient depth within the second layer 1112 such that the bases 1122 are positioned or embedded within the staple cavities 1115. In various other embodiments, the bases 1122 may not be positioned or embedded within the second layer 1112. In certain embodiments, referring again to FIG. 7A, the bases 1122 may extend below the bottom surface 1118 of the cartridge body 1110. In certain embodiments, the bases 1122 can rest on, or can be directly positioned against, the cartridge support surface 1130. In various embodiments, the cartridge support surface 1130 can comprise support features extending therefrom and/or defined therein wherein, in at least one such embodiment, the bases 1122 of the staples 1120 may be positioned within and supported by one or more support grooves, slots, or troughs, 1132, for example, in the staple cartridge support 1130, as described in greater detail further below.

[0315] In various embodiments, referring now to FIGS. 8 and 9, a staple cartridge, such as staple cartridge 1200, for example, can comprise a compressible, implantable cartridge body 1210 comprising an outer layer 1211 and an inner layer 1212. Similar to the above, the staple cartridge 1200 can comprise a plurality of staples 1220 positioned within the cartridge body 1210. In various embodiments, each staple 1220 can comprise a base 1222 and one or more staple legs 1221 extending therefrom. In at least one such embodiment, the staple legs 1221 can be inserted into the inner layer 1212 and seated to a depth in which the bases 1222 of the staples 1220 abut and/or are positioned adjacent to the bottom surface 1218 of the inner layer 1212, for example. In the embodiment depicted in FIGS. 8 and 9, the inner layer 1212 does not comprise staple cavities configured to receive a portion of the staples 1220 while, in other embodiments, the inner layer 1212 can comprise such staple cavities. In various embodiments, further to the above, the inner layer 1212 can be comprised of a compressible material, such as bioabsorbable foam and/or oxidized regenerated cellulose (ORC), for example, which can be configured to allow the cartridge body 1210 to collapse when a compressive load is applied thereto. In various embodiments, the inner layer 1212 can be comprised of a lyophilized foam comprising polylactic acid (PLA) and/or polyglycolic acid (PGA), for example. The ORC may be commercially available under the trade name Surgicel and can comprise a loose woven fabric (like a surgical sponge), loose fibers (like a cotton ball), and/or a foam. In at least one embodiment, the inner layer 1212 can be comprised of a material including medicaments, such as freeze-dried thrombin and/or fibrin, for example, contained therein and/or coated thereon which can be water-activated and/or activated by fluids within the patient's body, for example. In at least one such embodiment, the freeze-dried thrombin and/or fibrin can be held on a Vicryl (PGA) matrix, for example. In certain circumstances, however, the activatable medicaments can be unintentionally activated when the staple cartridge 1200 is inserted into a surgical site within the patient, for example. In various embodiments, referring again to FIGS. 8 and 9, the outer layer 1211 can be comprised of a water impermeable, or at least substantially water impermeable, material such that liquids do not come into contact with, or at least substantially contact, the inner layer 1212 until after the cartridge body 1210 has been compressed and the staple legs have penetrated the outer layer 1211 and/or after the outer layer 1211 has been incised in some fashion. In various embodiments, the outer layer 1211 can be comprised of a buttress material and/or plastic material, such as polydioxanone (PDS) and/or polyglycolic acid (PGA), for example. In certain embodiments, the outer layer 1211 can comprise a wrap which surrounds the inner layer 1212 and the staples 1220. More particularly, in at least one embodiment, the staples 1220 can be inserted into the inner layer 1212 and the outer layer 1211 can be wrapped around the sub-assembly comprising the inner layer 1212 and the staples 1220 and then sealed.

[0316] In various embodiments described herein, the staples of a staple cartridge can be fully formed by an anvil when the anvil is moved into a closed position. In various other embodiments, referring now to FIGS. 10-13, the staples of a staple cartridge, such as staple cartridge 4100, for example, can be deformed by an anvil when the anvil is moved into a closed position and, in addition, by a staple driver system which moves the staples toward the closed anvil. The staple cartridge 4100 can comprise a compressible cartridge body 4110 which can be comprised of a foam material, for example, and a plurality of staples 4120 at least partially positioned within the compressible cartridge body 4110. In various embodiments, the staple driver system can comprise a driver holder 4160, a plurality of staple drivers 4162 positioned within the driver holder 4160, and a staple cartridge pan 4180 which can be configured to retain the staple drivers 4162 in the driver holder 4160. In at least one such embodiment, the staple drivers 4162 can be positioned within one or more slots 4163 in the driver holder 4160 wherein the sidewalls of the slots 4163 can assist in guiding the staple drivers 4162 upwardly toward the anvil. In various embodiments, the staples 4120 can be supported within the slots 4163 by the staple drivers 4162 wherein, in at least one embodiment, the staples 4120 can be entirely positioned in the slots 4163 when the staples 4120 and the staple drivers 4162 are in their unfired positions. In certain other embodiments, at least a portion of the staples 4120 can extend upwardly through the open ends 4161 of slots 4163 when the staples 4120 and staple drivers 4162 are in their unfired positions. In at least one such embodiment, referring primarily now to FIG. 11, the bases of the staples 4120 can be positioned within the driver holder 4160 and the tips of the staples 4120 can be embedded within the compressible cartridge body 4110. In certain embodiments, approximately one-third of the height of the staples 4120 can be positioned within the driver holder 4160 and approximately two-thirds of the height of the staples 4120 can be positioned within the cartridge body 4110. In at least one embodiment, referring to FIG. 10A, the staple cartridge 4100 can further comprise a water impermeable wrap or membrane 4111 surrounding the cartridge body 4110 and the driver holder 4160, for example.

[0317] In use, the staple cartridge 4100 can be positioned within a staple cartridge channel, for example, and the anvil can be moved toward the staple cartridge 4100 into a closed position. In various embodiments, the anvil can contact and compress the compressible cartridge body 4110 when the anvil is moved into its closed position. In certain embodiments, the anvil may not contact the staples 4120 when the anvil is in its closed position. In certain other embodiments, the anvil may contact the legs of the staples 4120 and at least partially deform the staples 4120 when the anvil is moved into its closed position. In either event, the staple cartridge 4100 can further comprise one or more sleds 4170 which can be advanced longitudinally within the staple cartridge 4100 such that the sleds 4170 can sequentially engage the staple drivers 4162 and move the staple drivers 4162 and the staples 4120 toward the anvil. In various embodiments, the sleds 4170 can slide between the staple cartridge pan 4180 and the staple drivers 4162. In embodiments where the closure of the anvil has started the forming process of the staples 4120, the upward movement of the staples 4120 toward the anvil can complete the forming process and deform the staples 4120 to their fully formed, or at least desired, height. In embodiments where the closure of the anvil has not deformed the staples 4120, the upward movement of the staples 4120 toward the anvil can initiate and complete the forming process and deform the staples 4120 to their fully formed, or at least desired, height. In various embodiments, the sleds 4170 can be advanced from a proximal end of the staple cartridge 4100 to a distal end of the staple cartridge 4100 such that the staples 4120 positioned in the proximal end of the staple cartridge 4100 are fully formed before the staples 4120 positioned in the distal end of the staple cartridge 4100 are fully formed. In at least one embodiment, referring to FIG. 12, the sleds 4170 can each comprise at least one angled or inclined surface 4711 which can be configured to slide underneath the staple drivers 4162 and lift the staple drivers 4162 as illustrated in FIG. 13.

[0318] In various embodiments, further to the above, the staples 4120 can be formed in order to capture at least a portion of the tissue T and at least a portion of the compressible cartridge body 4110 of the staple cartridge 4100 therein. After the staples 4120 have been formed, the anvil and the staple cartridge channel 4130 of the surgical stapler can be moved away from the implanted staple cartridge 4100. In various circumstances, the cartridge pan 4180 can be fixedly engaged with the staple cartridge channel 4130 wherein, as a result, the cartridge pan 4180 can become detached from the compressible cartridge body 4110 as the staple cartridge channel 4130 is pulled away from the implanted cartridge body 4110. In various embodiments, referring again to FIG. 10, the cartridge pan 4180 can comprise opposing side walls 4181 between which the cartridge body 4110 can be removably positioned. In at least one such embodiment, the compressible cartridge body 4110 can be compressed between the side walls 4181 such that the cartridge body 4110 can be removably retained therebetween during use and releasably disengaged from the cartridge pan 4180 as the cartridge pan 4180 is pulled away. In at least one such embodiment, the driver holder 4160 can be connected to the cartridge pan 4180 such that the driver holder 4160, the drivers 4162, and/or the sleds 4170 can remain in the cartridge pan 4180 when the cartridge pan 4180 is removed from the surgical site. In certain other embodiments, the drivers 4162 can be ejected from the driver holder 4160 and left within the surgical site. In at least one such embodiment, the drivers 4162 can be comprised of a bioabsorbable material, such as polyglycolic acid (PGA) which is marketed under the trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. In various embodiments, the drivers 4162 can be attached to the staples 4120 such that the drivers 4162 are deployed with the staples 4120. In at least one such embodiment, each driver 4162 can comprise a trough configured to receive the bases of the staples 4120, for example, wherein, in at least one embodiment, the troughs can be configured to receive the staple bases in a press-fit and/or snap-fit manner.

[0319] In certain embodiments, further to the above, the driver holder 4160 and/or the sleds 4170 can be ejected from the cartridge pan 4180. In at least one such embodiment, the sleds 4170 can slide between the cartridge pan 4180 and the driver holder 4160 such that, as the sleds 4170 are advanced in order to drive the staple drivers 4162 and staples 4120 upwardly, the sleds 4170 can move the driver holder 4160 upwardly out of the cartridge pan 4180 as well. In at least one such embodiment, the driver holder 4160 and/or the sleds 4170 can be comprised of a bioabsorbable material, such as polyglycolic acid (PGA) which is marketed under the trade name Vicryl, polylactic acid (PLA or PLLA), polydioxanone (PDS), polyhydroxyalkanoate (PHA), poliglecaprone 25 (PGCL) which is marketed under the trade name Monocryl, polycaprolactone (PCL), and/or a composite of PGA, PLA, PDS, PHA, PGCL and/or PCL, for example. In various embodiments, the sleds 4170 can be integrally formed and/or attached to a drive bar, or cutting member, which pushes the sleds 4170 through the staple cartridge 4100. In such embodiments, the sleds 4170 may not be ejected from the cartridge pan 4180 and may remain with the surgical stapler while, in other embodiments in which the sleds 4170 are not attached to the drive bar, the sleds 4170 may be left in the surgical site. In any event, further to the above, the compressibility of the cartridge body 4110 can allow thicker staple cartridges to be used within an end effector of a surgical stapler as the cartridge body 4110 can compress, or shrink, when the anvil of the stapler is closed. In certain embodiments, as a result of the staples being at least partially deformed upon the closure of the anvil, taller staples, such as staples having an approximately 0.18″ staple height, for example, could be used, wherein approximately 0.12″ of the staple height can be positioned within the compressible layer 4110 and wherein the compressible layer 4110 can have an uncompressed height of approximately 0.14″, for example.

[0320] In many embodiments described herein, a staple cartridge can comprise a plurality of staples therein. In various embodiments, such staples can be comprised of a metal wire deformed into a substantially U-shaped configuration having two staple legs. Other embodiments are envisioned in which staples can comprise different configurations such as two or more wires that have been joined together having three or more staple legs. In various embodiments, the wire, or wires, used to form the staples can comprise a round, or at least substantially round, cross-section. In at least one embodiment, the staple wires can comprise any other suitable cross-section, such as square and/or rectangular cross-sections, for example. In certain embodiments, the staples can be comprised of plastic wires. In at least one embodiment, the staples can be comprised of plastic-coated metal wires. In various embodiments, a cartridge can comprise any suitable type of fastener in addition to or in lieu of staples. In at least one such embodiment, such a fastener can comprise pivotable arms which are folded when engaged by an anvil. In certain embodiments, two-part fasteners could be utilized. In at least one such embodiment, a staple cartridge can comprise a plurality of first fastener portions and an anvil can comprise a plurality of second fastener portions which are connected to the first fastener portions when the anvil is compressed against the staple cartridge. In certain embodiments, as described above, a sled or driver can be advanced within a staple cartridge in order to complete the forming process of the staples. In certain embodiments, a sled or driver can be advanced within an anvil in order to move one or more forming members downwardly into engagement with the opposing staple cartridge and the staples, or fasteners, positioned therein.

[0321] In various embodiments described herein, a staple cartridge can comprise four rows of staples stored therein. In at least one embodiment, the four staple rows can be arranged in two inner staple rows and two outer staple rows. In at least one such embodiment, an inner staple row and an outer staple row can be positioned on a first side of a cutting member, or knife, slot within the staple cartridge and, similarly, an inner staple row and an outer staple row can be positioned on a second side of the cutting member, or knife, slot. In certain embodiments, a staple cartridge may not comprise a cutting member slot; however, such a staple cartridge may comprise a designated portion configured to be incised by a cutting member in lieu of a staple cartridge slot. In various embodiments, the inner staple rows can be arranged within the staple cartridge such that they are equally, or at least substantially equally, spaced from the cutting member slot. Similarly, the outer staple rows can be arranged within the staple cartridge such that they are equally, or at least substantially equally, spaced from the cutting member slot. In various embodiments, a staple cartridge can comprise more than or less than four rows of staples stored within a staple cartridge. In at least one embodiment, a staple cartridge can comprise six rows of staples. In at least one such embodiment, the staple cartridge can comprise three rows of staples on a first side of a cutting member slot and three rows of staples on a second side of the cutting member slot. In certain embodiments, a staple cartridge may comprise an odd number of staple rows. For example, a staple cartridge may comprise two rows of staples on a first side of a cutting member slot and three rows of staples on a second side of the cutting member slot. In various embodiments, the staple rows can comprise staples having the same, or at least substantially the same, unformed staple height. In certain other embodiments, one or more of the staple rows can comprise staples having a different unformed staple height than the other staples. In at least one such embodiment, the staples on a first side of a cutting member slot may have a first unformed height and the staples on a second side of a cutting member slot may have a second unformed height which is different than the first height, for example.

[0322] In various embodiments, as described above, a staple cartridge can comprise a cartridge body including a plurality of staple cavities defined therein. The cartridge body can comprise a deck and a top deck surface wherein each staple cavity can define an opening in the deck surface. As also described above, a staple can be positioned within each staple cavity such that the staples are stored within the cartridge body until they are ejected therefrom. Prior to being ejected from the cartridge body, in various embodiments, the staples can be contained with the cartridge body such that the staples do not protrude above the deck surface. As the staples are positioned below the deck surface, in such embodiments, the possibility of the staples becoming damaged and/or prematurely contacting the targeted tissue can be reduced. In various circumstances, the staples can be moved between an unfired position in which they do not protrude from the cartridge body and a fired position in which they have emerged from the cartridge body and can contact an anvil positioned opposite the staple cartridge. In various embodiments, the anvil, and/or the forming pockets defined within the anvil, can be positioned a predetermined distance above the deck surface such that, as the staples are being deployed from the cartridge body, the staples are deformed to a predetermined formed height. In some circumstances, the thickness of the tissue captured between the anvil and the staple cartridge may vary and, as a result, thicker tissue may be captured within certain staples while thinner tissue may be captured within certain other staples. In either event, the clamping pressure, or force, applied to the tissue by the staples may vary from staple to staple or vary between a staple on one end of a staple row and a staple on the other end of the staple row, for example. In certain circumstances, the gap between the anvil and the staple cartridge deck can be controlled such that the staples apply a certain minimum clamping pressure within each staple. In some such circumstances, however, significant variation of the clamping pressure within different staples may still exist. Surgical stapling instruments are disclosed in U.S. Pat. No. 7,380,696, which issued on Jun. 3, 2008, the entire disclosure of which is incorporated by reference herein. An illustrative multi-stroke handle for the surgical stapling and severing instrument is described in greater detail in the co-pending and co-owned U.S. patent application entitled SURGICAL STAPLING INSTRUMENT INCORPORATING A MULTISTROKE FIRING POSITION INDICATOR AND RETRACTION MECHANISM, Ser. No. 10/674,026, now U.S. Pat. No. 7,364,061, which issued on Apr. 29, 2008, the disclosure of which is hereby incorporated by reference in its entirety. Other applications consistent with the present invention may incorporate a single firing stroke, such as described in co-pending and commonly owned U.S. patent application SURGICAL STAPLING INSTRUMENT HAVING SEPARATE DISTINCT CLOSING AND FIRING SYSTEMS, Ser. No. 10/441,632, now U.S. Pat. No. 7,000,818, which issued on Feb. 21, 2006, the disclosure of which is hereby incorporated by reference in its entirety.

[0323] In various embodiments described herein, a staple cartridge can comprise means for compensating for the thickness of the tissue captured within the staples deployed from the staple cartridge. In various embodiments, referring to FIG. 14, a staple cartridge, such as staple cartridge 10000, for example, can include a rigid first portion, such as support portion 10010, for example, and a compressible second portion, such as tissue thickness compensator 10020, for example. In at least one embodiment, referring primarily to FIG. 16, the support portion 10010 can comprise a cartridge body, a top deck surface 10011, and a plurality of staple cavities 10012 wherein, similar to the above, each staple cavity 10012 can define an opening in the deck surface 10011. A staple 10030, for example, can be removably positioned in each staple cavity 10012. In at least one such embodiment, each staple 10030 can comprise a base 10031 and one or more legs 10032 extending from the base 10031. Prior to the staples 10030 being deployed, as also described in greater detail below, the bases 10031 of the staples 10030 can be supported by staple drivers positioned within the support portion 10010 and, concurrently, the legs 10032 of the staples 10030 can be at least partially contained within the staple cavities 10012. In various embodiments, the staples 10030 can be deployed between an unfired position and a fired position such that the legs 10032 move through the tissue thickness compensator 10020, penetrate through a top surface of the tissue thickness compensator 10020, penetrate the tissue T, and contact an anvil positioned opposite the staple cartridge 10000. As the legs 10032 are deformed against the anvil, the legs 10032 of each staple 10030 can capture a portion of the tissue thickness compensator 10020 and a portion of the tissue T within each staple 10030 and apply a compressive force to the tissue. Further to the above, the legs 10032 of each staple 10030 can be deformed downwardly toward the base 10031 of the staple to form a staple entrapment area 10039 in which the tissue T and the tissue thickness compensator 10020 can be captured. In various circumstances, the staple entrapment area 10039 can be defined between the inner surfaces of the deformed legs 10032 and the inner surface of the base 10031. The size of the entrapment area for a staple can depend on several factors such as the length of the legs, the diameter of the legs, the width of the base, and/or the extent in which the legs are deformed, for example.

[0324] In previous embodiments, a surgeon was often required to select the appropriate staples having the appropriate staple height for the tissue being stapled. For example, a surgeon could select tall staples for use with thick tissue and short staples for use with thin tissue. In some circumstances, however, the tissue being stapled did not have a consistent thickness and, thus, some staples were unable to achieve the desired fired configuration. For example, FIG. 48 illustrates a tall staple used in thin tissue. Referring now to FIG. 49, when a tissue thickness compensator, such as tissue thickness compensator 10020, for example, is used with thin tissue, for example, the larger staple may be formed to a desired fired configuration.

[0325] Owing to the compressibility of the tissue thickness compensator, the tissue thickness compensator can compensate for the thickness of the tissue captured within each staple. More particularly, referring now to FIGS. 43 and 44, a tissue thickness compensator, such as tissue thickness compensator 10020, for example, can consume larger and/or smaller portions of the staple entrapment area 10039 of each staple 10030 depending on the thickness and/or type of tissue contained within the staple entrapment area 10039. For example, if thinner tissue T is captured within a staple 10030, the tissue thickness compensator 10020 can consume a larger portion of the staple entrapment area 10039 as compared to circumstances where thicker tissue T is captured within the staple 10030. Correspondingly, if thicker tissue T is captured within a staple 10030, the tissue thickness compensator 10020 can consume a smaller portion of the staple entrapment area 10039 as compared to the circumstances where thinner tissue T is captured within the staple 10030. In this way, the tissue thickness compensator can compensate for thinner tissue and/or thicker tissue and assure that a compressive pressure is applied to the tissue irrespective, or at least substantially irrespective, of the tissue thickness captured within the staples. In addition to the above, the tissue thickness compensator 10020 can compensate for different types, or compressibilities, of tissues captured within different staples 10030. Referring now to FIG. 44, the tissue thickness compensator 10020 can apply a compressive force to vascular tissue T which can include vessels V and, as a result, restrict the flow of blood through the less compressible vessels V while still applying a desired compressive pressure to the surrounding tissue T. In various circumstances, further to the above, the tissue thickness compensator 10020 can also compensate for malformed staples. Referring to FIG. 45, the malformation of various staples 10030 can result in larger staple entrapment areas 10039 being defined within such staples. Owing to the resiliency of the tissue thickness compensator 10020, referring now to FIG. 46, the tissue thickness compensator 10020 positioned within malformed staples 10030 may still apply a sufficient compressive pressure to the tissue T even though the staple entrapment areas 10039 defined within such malformed staples 10030 may be enlarged. In various circumstances, the tissue thickness compensator 10020 located intermediate adjacent staples 10030 can be biased against the tissue T by properly-formed staples 10030 surrounding a malformed staple 10030 and, as a result, apply a compressive pressure to the tissue surrounding and/or captured within the malformed staple 10030, for example. In various circumstances, a tissue thickness compensator can compensate for different tissue densities which can arise due to calcifications, fibrous areas, and/or tissue that has been previously stapled or treated, for example.

[0326] In various embodiments, a fixed, or unchangeable, tissue gap can be defined between the support portion and the anvil and, as a result, the staples may be deformed to a predetermined height regardless of the thickness of the tissue captured within the staples. When a tissue thickness compensator is used with these embodiments, the tissue thickness compensator can adapt to the tissue captured between the anvil and the support portion staple cartridge and, owing to the resiliency of the tissue thickness compensator, the tissue thickness compensator can apply an additional compressive pressure to the tissue. Referring now to FIGS. 50-55, a staple 10030 has been formed to a predefined height H. With regard to FIG. 50, a tissue thickness compensator has not been utilized and the tissue T consumes the entirety of the staple entrapment area 10039. With regard to FIG. 57, a portion of a tissue thickness compensator 10020 has been captured within the staple 10030, compressed the tissue T, and consumed at least a portion of the staple entrapment area 10039. Referring now to FIG. 52, thin tissue T has been captured within the staple 10030. In this embodiment, the compressed tissue T has a height of approximately 2/9H and the compressed tissue thickness compensator 10020 has a height of approximately 7/9H, for example. Referring now to FIG. 53, tissue T having an intermediate thickness has been captured within the staple 10030. In this embodiment, the compressed tissue T has a height of approximately 4/9H and the compressed tissue thickness compensator 10020 has a height of approximately 5/9H, for example. Referring now to FIG. 54, tissue T having an intermediate thickness has been captured within the staple 10030. In this embodiment, the compressed tissue T has a height of approximately ⅔H and the compressed tissue thickness compensator 10020 has a height of approximately ⅓H, for example. Referring now to FIG. 53, thick tissue T has been captured within the staple 10030. In this embodiment, the compressed tissue T has a height of approximately 8/9H and the compressed tissue thickness compensator 10020 has a height of approximately 1/9H, for example. In various circumstances, the tissue thickness compensator can comprise a compressed height which comprises approximately 10% of the staple entrapment height, approximately 20% of the staple entrapment height, approximately 30% of the staple entrapment height, approximately 40% of the staple entrapment height, approximately 50% of the staple entrapment height, approximately 60% of the staple entrapment height, approximately 70% of the staple entrapment height, approximately 80% of the staple entrapment height, and/or approximately 90% of the staple entrapment height, for example.

[0327] In various embodiments, the staples 10030 can comprise any suitable unformed height. In certain embodiments, the staples 10030 can comprise an unformed height between approximately 2 mm and approximately 4.8 mm, for example. The staples 10030 can comprise an unformed height of approximately 2.0 mm, approximately 2.5 mm, approximately 3.0 mm, approximately 3.4 mm, approximately 3.5 mm, approximately 3.8 mm, approximately 4.0 mm, approximately 4.1 mm, and/or approximately 4.8 mm, for example. In various embodiments, the height H to which the staples can be deformed can be dictated by the distance between the deck surface 10011 of the support portion 10010 and the opposing anvil. In at least one embodiment, the distance between the deck surface 10011 and the tissue-contacting surface of the anvil can be approximately 0.097″, for example. The height H can also be dictated by the depth of the forming pockets defined within the anvil. In at least one embodiment, the forming pockets can have a depth measured from the tissue-contacting surface, for example. In various embodiments, as described in greater detail below, the staple cartridge 10000 can further comprise staple drivers which can lift the staples 10030 toward the anvil and, in at least one embodiment, lift, or “overdrive”, the staples above the deck surface 10011. In such embodiments, the height H to which the staples 10030 are formed can also be dictated by the distance in which the staples 10030 are overdriven. In at least one such embodiment, the staples 10030 can be overdriven by approximately 0.028″, for example, and can result in the staples 10030 being formed to a height of approximately 0.189″, for example. In various embodiments, the staples 10030 can be formed to a height of approximately 0.8 mm, approximately 1.0 mm, approximately 1.5 mm, approximately 1.8 mm, approximately 2.0 mm, and/or approximately 2.25 mm, for example. In certain embodiments, the staples can be formed to a height between approximately 2.25 mm and approximately 3.0 mm, for example. Further to the above, the height of the staple entrapment area of a staple can be determined by the formed height of the staple and the width, or diameter, of the wire comprising the staple. In various embodiments, the height of the staple entrapment area 10039 of a staple 10030 can comprise the formed height H of the staple less two diameter widths of the wire. In certain embodiments, the staple wire can comprise a diameter of approximately 0.0089″, for example. In various embodiments, the staple wire can comprise a diameter between approximately 0.0069″ and approximately 0.0119″, for example. In at least one exemplary embodiment, the formed height H of a staple 10030 can be approximately 0.189″ and the staple wire diameter can be approximately 0.0089″ resulting in a staple entrapment height of approximately 0.171″, for example.

[0328] In various embodiments, further to the above, the tissue thickness compensator can comprise an uncompressed, or pre-deployed, height and can be configured to deform to one of a plurality of compressed heights. In certain embodiments, the tissue thickness compensator can comprise an uncompressed height of approximately 0.125″, for example. In various embodiments, the tissue thickness compensator can comprise an uncompressed height of greater than or equal to approximately 0.080″, for example. In at least one embodiment, the tissue thickness compensator can comprise an uncompressed, or pre-deployed, height which is greater than the unfired height of the staples. In at least one embodiment, the uncompressed, or pre-deployed, height of the tissue thickness compensator can be approximately 10% taller, approximately 20% taller, approximately 30% taller, approximately 40% taller, approximately 50% taller, approximately 60% taller, approximately 70% taller, approximately 80% taller, approximately 90% taller, and/or approximately 100% taller than the unfired height of the staples, for example. In at least one embodiment, the uncompressed, or pre-deployed, height of the tissue thickness compensator can be up to approximately 100% taller than the unfired height of the staples, for example. In certain embodiments, the uncompressed, or pre-deployed, height of the tissue thickness compensator can be over 100% taller than the unfired height of the staples, for example. In at least one embodiment, the tissue thickness compensator can comprise an uncompressed height which is equal to the unfired height of the staples. In at least one embodiment, the tissue thickness compensator can comprise an uncompressed height which is less than the unfired height of the staples. In at least one embodiment, the uncompressed, or pre-deployed, height of the thickness compensator can be approximately 10% shorter, approximately 20% shorter, approximately 30% shorter, approximately 40% shorter, approximately 50% shorter, approximately 60% shorter, approximately 70% shorter, approximately 80% shorter, and/or approximately 90% shorter than the unfired height of the staples, for example. In various embodiments, the compressible second portion can comprise an uncompressed height which is taller than an uncompressed height of the tissue T being stapled. In certain embodiments, the tissue thickness compensator can comprise an uncompressed height which is equal to an uncompressed height of the tissue T being stapled. In various embodiments, the tissue thickness compensator can comprise an uncompressed height which is shorter than an uncompressed height of the tissue T being stapled.

[0329] As described above, a tissue thickness compensator can be compressed within a plurality of formed staples regardless of whether thick tissue or thin tissue is captured within the staples. In at least one exemplary embodiment, the staples within a staple line, or row, can be deformed such that the staple entrapment area of each staple comprises a height of approximately 2.0 mm, for example, wherein the tissue T and the tissue thickness compensator can be compressed within this height. In certain circumstances, the tissue T can comprise a compressed height of approximately 1.75 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 0.25 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example. In certain circumstances, the tissue T can comprise a compressed height of approximately 1.50 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 0.50 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example. In certain circumstances, the tissue T can comprise a compressed height of approximately 1.25 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 0.75 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example. In certain circumstances, the tissue T can comprise a compressed height of approximately 1.0 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 1.0 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example. In certain circumstances, the tissue T can comprise a compressed height of approximately 0.75 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 1.25 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example. In certain circumstances, the tissue T can comprise a compressed height of approximately 1.50 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 0.50 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example. In certain circumstances, the tissue T can comprise a compressed height of approximately 0.25 mm within the staple entrapment area while the tissue thickness compensator can comprise a compressed height of approximately 1.75 mm within the staple entrapment area, thereby totaling the approximately 2.0 mm staple entrapment area height, for example.

[0330] In various embodiments, further to the above, the tissue thickness compensator can comprise an uncompressed height which is less than the fired height of the staples. In certain embodiments, the tissue thickness compensator can comprise an uncompressed height which is equal to the fired height of the staples. In certain other embodiments, the tissue thickness compensator can comprise an uncompressed height which is taller than the fired height of the staples. In at least one such embodiment, the uncompressed height of a tissue thickness compensator can comprise a thickness which is approximately 110% of the formed staple height, approximately 120% of the formed staple height, approximately 130% of the formed staple height, approximately 140% of the formed staple height, approximately 150% of the formed staple height, approximately 160% of the formed staple height, approximately 170% of the formed staple height, approximately 180% of the formed staple height, approximately 190% of the formed staple height, and/or approximately 200% of the formed staple height, for example. In certain embodiments, the tissue thickness compensator can comprise an uncompressed height which is more than twice the fired height of the staples. In various embodiments, the tissue thickness compensator can comprise a compressed height which is from approximately 85% to approximately 150% of the formed staple height, for example. In various embodiments, as described above, the tissue thickness compensator can be compressed between an uncompressed thickness and a compressed thickness. In certain embodiments, the compressed thickness of a tissue thickness compensator can be approximately 10% of its uncompressed thickness, approximately 20% of its uncompressed thickness, approximately 30% of its uncompressed thickness, approximately 40% of its uncompressed thickness, approximately 50% of its uncompressed thickness, approximately 60% of its uncompressed thickness, approximately 70% of its uncompressed thickness, approximately 80% of its uncompressed thickness, and/or approximately 90% of its uncompressed thickness, for example. In various embodiments, the uncompressed thickness of the tissue thickness compensator can be approximately two times, approximately ten times, approximately fifty times, and/or approximately one hundred times thicker than its compressed thickness, for example. In at least one embodiment, the compressed thickness of the tissue thickness compensator can be between approximately 60% and approximately 99% of its uncompressed thickness. In at least one embodiment, the uncompressed thickness of the tissue thickness compensator can be at least 50% thicker than its compressed thickness. In at least one embodiment, the uncompressed thickness of the tissue thickness compensator can be up to one hundred times thicker than its compressed thickness. In various embodiments, the compressible second portion can be elastic, or at least partially elastic, and can bias the tissue T against the deformed legs of the staples. In at least one such embodiment, the compressible second portion can resiliently expand between the tissue T and the base of the staple in order to push the tissue T against the legs of the staple. In certain embodiments, discussed in further detail below, the tissue thickness compensator can be positioned intermediate the tissue T and the deformed staple legs. In various circumstances, as a result of the above, the tissue thickness compensator can be configured to consume any gaps within the staple entrapment area.

[0331] In various embodiments, the tissue thickness compensator may comprise materials characterized by one or more of the following properties: biocompatible, bioabsorable, bioresorbable, biodurable, biodegradable, compressible, fluid absorbable, swellable, self-expandable, bioactive, medicament, pharmaceutically active, anti-adhesion, haemostatic, antibiotic, anti-microbial, anti-viral, nutritional, adhesive, permeable, hydrophilic and/or hydrophobic, for example. In various embodiments, a surgical instrument comprising an anvil and a staple cartridge may comprise a tissue thickness compensator associated with the anvil and/or staple cartridge comprising at least one of a haemostatic agent, such as fibrin and thrombin, an antibiotic, such as doxycpl, and mendicant, such as matrix metalloproteinases (MMPs).

[0332] In various embodiments, the tissue thickness compensator may comprise synthetic and/or non-synthetic materials. The tissue thickness compensator may comprise a polymeric composition comprising one or more synthetic polymers and/or one or more non-synthetic polymers. The synthetic polymer may comprise a synthetic absorbable polymer and/or a synthetic non-absorbable polymer. In various embodiments, the polymeric composition may comprise a biocompatible foam, for example. The biocompatible foam may comprise a porous, open cell foam and/or a porous, closed cell foam, for example. The biocompatible foam may have a uniform pore morphology or may have a gradient pore morphology (i.e. small pores gradually increasing in size to large pores across the thickness of the foam in one direction). In various embodiments, the polymeric composition may comprise one or more of a porous scaffold, a porous matrix, a gel matrix, a hydrogel matrix, a solution matrix, a filamentous matrix, a tubular matrix, a composite matrix, a membranous matrix, a biostable polymer, and a biodegradable polymer, and combinations thereof. For example, the tissue thickness compensator may comprise a foam reinforced by a filamentous matrix or may comprise a foam having an additional hydrogel layer that expands in the presence of bodily fluids to further provide the compression on the tissue. In various embodiments, a tissue thickness compensator could also be comprised of a coating on a material and/or a second or third layer that expands in the presence of bodily fluids to further provide the compression on the tissue. Such a layer could be a hydrogel that could be a synthetic and/or naturally derived material and could be either biodurable and/or biodegradable, for example. In various embodiments, the tissue thickness compensator may comprise a microgel or a nanogel. The hydrogel may comprise carbohydrate-derived microgels and/or nanogels. In certain embodiments, a tissue thickness compensator may be reinforced with fibrous non-woven materials or fibrous mesh type elements, for example, that can provide additional flexibility, stiffness, and/or strength. In various embodiments, a tissue thickness compensator that has a porous morphology which exhibits a gradient structure such as, for example, small pores on one surface and larger pores on the other surface. Such morphology could be more optimal for tissue in-growth or haemostatic behavior. Further, the gradient could be also compositional with a varying bio-absorption profile. A short term absorption profile may be preferred to address hemostasis while a long term absorption profile may address better tissue healing without leakages.

[0333] Examples of non-synthetic materials include, but are not limited to, lyophilized polysaccharide, glycoprotein, bovine pericardium, collagen, gelatin, fibrin, fibrinogen, elastin, proteoglycan, keratin, albumin, hydroxyethyl cellulose, cellulose, oxidized cellulose, oxidized regenerated cellulose (ORC), hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethylcellulose, chitan, chitosan, casein, alginate, and combinations thereof.

[0334] Examples of synthetic absorbable materials include, but are not limited to, poly(lactic acid) (PLA), poly(L-lactic acid) (PLLA), polycaprolactone (PCL), polyglycolic acid (PGA), poly(trimethylene carbonate) (TMC), polyethylene terephthalate (PET), polyhydroxyalkanoate (PHA), a copolymer of glycolide and ε-caprolactone (PGCL), a copolymer of glycolide and -trimethylene carbonate, poly(glycerol sebacate) (PGS), poly(dioxanone) (PDS), polyesters, poly(orthoesters), polyoxaesters, polyetheresters, polycarbonates, polyamide esters, polyanhydrides, polysaccharides, poly(ester-amides), tyrosine-based polyarylates, polyamines, tyrosine-based polyiminocarbonates, tyrosine-based polycarbonates, poly(D,L-lactide-urethane), poly(hydroxybutyrate), poly(B-hydroxybutyrate), poly(ε-caprolactone), polyethyleneglycol (PEG), poly[bis(carboxylatophenoxy)phosphazene]poly(amino acids), pseudo-poly(amino acids), absorbable polyurethanes, poly(phosphazine), polyphosphazenes, polyalkyleneoxides, polyacrylamides, polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinyl alcohols, poly(caprolactone), polyacrylic acid, polyacetate, polypropylene, aliphatic polyesters, glycerols, copoly(ether-esters), polyalkylene oxalates, polyamides, poly(iminocarbonates), polyalkylene oxalates, and combinations thereof. In various embodiments, the polyester is may be selected from the group consisting of polylactides, polyglycolides, trimethylene carbonates, polydioxanones, polycaprolactones, polybutesters, and combinations thereof.

[0335] In various embodiments, the synthetic absorbable polymer may comprise one or more of 90/10 poly(glycolide-L-lactide) copolymer, commercially available from Ethicon, Inc. under the trade designation VICRYL (polyglactic 910), polyglycolide, commercially available from American Cyanamid Co. under the trade designation DEXON, polydioxanone, commercially available from Ethicon, Inc. under the trade designation PDS, poly(glycolide-trimethylene carbonate) random block copolymer, commercially available from American Cyanamid Co. under the trade designation MAXON, 75/25 poly(glycolide-ε-caprolactone-poliglecaprolactone 25) copolymer, commercially available from Ethicon under the trade designation MONOCRYL, for example.

[0336] Examples of synthetic non-absorbable materials include, but are not limited to, polyurethane, polypropylene (PP), polyethylene (PE), polycarbonate, polyamides, such as nylon, polyvinylchloride (PVC), polymethylmetacrylate (PMMA), polystyrene (PS), polyester, polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), polytrifluorochloroethylene (PTFCE), polyvinylfluoride (PVF), fluorinated ethylene propylene (FEP), polyacetal, polysulfone, silicons, and combinations thereof. The synthetic non-absorbable polymers may include, but are not limited to, foamed elastomers and porous elastomers, such as, for example, silicone, polyisoprene, and rubber. In various embodiments, the synthetic polymers may comprise expanded polytetrafluoroethylene (ePTFE), commercially available from W. L. Gore & Associates, Inc. under the trade designation GORE-TEX Soft Tissue Patch and co-polyetherester urethane foam commercially available from Polyganics under the trade designation NASOPORE.

[0337] In various embodiments, the polymeric composition may comprise from approximately 50% to approximately 90% by weight of the polymeric composition of PLLA and approximately 50% to approximately 10% by weight of the polymeric composition of PCL, for example. In at least one embodiment, the polymeric composition may comprise approximately 70% by weight of PLLA and approximately 30% by weight of PCL, for example. In various embodiments, the polymeric composition may comprise from approximately 55% to approximately 85% by weight of the polymeric composition of PGA and 15% to 45% by weight of the polymeric composition of PCL, for example. In at least one embodiment, the polymeric composition may comprise approximately 65% by weight of PGA and approximately 35% by weight of PCL, for example. In various embodiments, the polymeric composition may comprise from approximately 90% to approximately 95% by weight of the polymeric composition of PGA and approximately 5% to approximately 10% by weight of the polymeric composition of PLA, for example.

[0338] In various embodiments, the synthetic absorbable polymer may comprise a bioabsorbable, biocompatible elastomeric copolymer. Suitable bioabsorbable, biocompatible elastomeric copolymers include but are not limited to copolymers of ε-caprolactone and glycolide (preferably having a mole ratio of ε-caprolactone to glycolide of from about 30:70 to about 70:30, preferably 35:65 to about 65:35, and more preferably 45:55 to 35:65); elastomeric copolymers of ε-caprolactone and lactide, including L-lactide, D-lactide blends thereof or lactic acid copolymers (preferably having a mole ratio of ε-caprolactone to lactide of from about 35:65 to about 65:35 and more preferably 45:55 to 30:70) elastomeric copolymers of p-dioxanone (1,4-dioxan-2-one) and lactide including L-lactide, D-lactide and lactic acid (preferably having a mole ratio of p-dioxanone to lactide of from about 40:60 to about 60:40); elastomeric copolymers of ε-caprolactone and p-dioxanone (preferably having a mole ratio of ε-caprolactone to p-dioxanone of from about 30:70 to about 70:30); elastomeric copolymers of p-dioxanone and trimethylene carbonate (preferably having a mole ratio of p-dioxanone to trimethylene carbonate of from about 30:70 to about 70:30); elastomeric copolymers of trimethylene carbonate and glycolide (preferably having a mole ratio of trimethylene carbonate to glycolide of from about 30:70 to about 70:30); elastomeric copolymer of trimethylene carbonate and lactide including L-lactide, D-lactide, blends thereof or lactic acid copolymers (preferably having a mole ratio of trimethylene carbonate to lactide of from about 30:70 to about 70:30) and blends thereof. In one embodiment, the elastomeric copolymer is a copolymer of glycolide and ε-caprolactone. In another embodiment, the elastomeric copolymer is a copolymer of lactide and ε-caprolactone.

[0339] The disclosures of U.S. Pat. No. 5,468,253, entitled ELASTOMERIC MEDICAL DEVICE, which issued on Nov. 21, 1995, and U.S. Pat. No. 6,325,810, entitled FOAM BUTTRESS FOR STAPLING APPARATUS, which issued on Dec. 4, 2001, are hereby incorporated by reference in their respective entireties.

[0340] In various embodiments, the tissue thickness compensator may comprise an emulsifier. Examples of emulsifiers may include, but are not limited to, water-soluble polymers, such as, polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG), polypropylene glycol (PPG), PLURONICS, TWEENS, polysaccharides and combinations thereof.

[0341] In various embodiments, the tissue thickness compensator may comprise a surfactant. Examples of surfactants may include, but are not limited to, polyacrylic acid, methalose, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, dialkylphenoxy poly(ethyleneoxy)ethanol, and polyoxamers.

[0342] In various embodiments, the polymeric composition may comprise a pharmaceutically active agent. The polymeric composition may release a therapeutically effective amount of the pharmaceutically active agent. In various embodiments, the pharmaceutically active agent may be released as the polymeric composition is desorbed/absorbed. In various embodiments, the pharmaceutically active agent may be released into fluid, such as, for example, blood, passing over or through the polymeric composition. Examples of pharmaceutically active agents may include, but are not limited to, haemostatic agents and drugs, such as, for example, fibrin, thrombin, and oxidized regenerated cellulose (ORC); anti-inflammatory drugs, such as, for example, diclofenac, aspirin, naproxen, sulindac, and hydrocortisone; antibiotic and antimicrobial drug or agents, such as, for example, triclosan, ionic silver, ampicillin, gentamicin, polymyxin B, chloramphenicol; and anticancer agents, such as, for example, cisplatin, mitomycin, adriamycin.

[0343] In various embodiments, the polymeric composition may comprise a haemostatic material. The tissue thickness compensator may comprise haemostatic materials comprising poly(lactic acid), poly(glycolic acid), poly(hydroxybutyrate), poly(caprolactone), poly(dioxanone), polyalkyleneoxides, copoly(ether-esters), collagen, gelatin, thrombin, fibrin, fibrinogen, fibronectin, elastin, albumin, hemoglobin, ovalbumin, polysaccharides, hyaluronic acid, chondroitin sulfate, hydroxyethyl starch, hydroxyethyl cellulose, cellulose, oxidized cellulose, hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethyl cellulose, chitan, chitosan, agarose, maltose, maltodextrin, alginate, clotting factors, methacrylate, polyurethanes, cyanoacrylates, platelet agonists, vasoconstrictors, alum, calcium, RGD peptides, proteins, protamine sulfate, ε-amino caproic acid, ferric sulfate, ferric subsulfates, ferric chloride, zinc, zinc chloride, aluminum chloride, aluminum sulfates, aluminum acetates, permanganates, tannins, bone wax, polyethylene glycols, fucans and combinations thereof. The tissue thickness compensator may be characterized by haemostatic properties.

[0344] The polymeric composition of a tissue thickness compensator may be characterized by percent porosity, pore size, and/or hardness, for example. In various embodiments, the polymeric composition may have a percent porosity from approximately 30% by volume to approximately 99% by volume, for example. In certain embodiments, the polymeric composition may have a percent porosity from approximately 60% by volume to approximately 98% by volume, for example. In various embodiments, the polymeric composition may have a percent porosity from approximately 85% by volume to approximately 97% by volume, for example. In at least one embodiment, the polymeric composition may comprise approximately 70% by weight of PLLA and approximately 30% by weight of PCL, for example, and can comprise approximately 90% porosity by volume, for example. In at least one such embodiment, as a result, the polymeric composition would comprise approximately 10% copolymer by volume. In at least one embodiment, the polymeric composition may comprise approximately 65% by weight of PGA and approximately 35% by weight of PCL, for example, and can have a percent porosity from approximately 93% by volume to approximately 95% by volume, for example. In various embodiments, the polymeric composition may comprise greater than 85% porosity by volume. The polymeric composition may have a pore size from approximately 5 micrometers to approximately 2000 micrometers, for example. In various embodiments, the polymeric composition may have a pore size between approximately 10 micrometers to approximately 100 micrometers, for example. In at least one such embodiment, the polymeric composition can comprise a copolymer of PGA and PCL, for example. In certain embodiments, the polymeric composition may have a pore size between approximately 100 micrometers to approximately 1000 micrometers, for example. In at least one such embodiment, the polymeric composition can comprise a copolymer of PLLA and PCL, for example.

[0345] According to certain aspects, the hardness of a polymeric composition may be expressed in terms of the Shore Hardness, which can defined as the resistance to permanent indentation of a material as determined with a durometer, such as a Shore Durometer. In order to assess the durometer value for a given material, a pressure is applied to the material with a durometer indenter foot in accordance with ASTM procedure D2240-00, entitled, “Standard Test Method for Rubber Property-Durometer Hardness”, the entirety of which is incorporated herein by reference. The durometer indenter foot may be applied to the material for a sufficient period of time, such as 15 seconds, for example, wherein a reading is then taken from the appropriate scale. Depending on the type of scale being used, a reading of 0 can be obtained when the indenter foot completely penetrates the material, and a reading of 100 can be obtained when no penetration into the material occurs. This reading is dimensionless. In various embodiments, the durometer may be determined in accordance with any suitable scale, such as Type A and/or Type OO scales, for example, in accordance with ASTM D2240-00. In various embodiments, the polymeric composition of a tissue thickness compensator may have a Shore A hardness value from approximately 4 A to approximately 16 A, for example, which is approximately 45 OO to approximately 65 OO on the Shore OO range. In at least one such embodiment, the polymeric composition can comprise a PLLA/PCL copolymer or a PGA/PCL copolymer, for example. In various embodiments, the polymeric composition of a tissue thickness compensator may have a Shore A Hardness value of less than 15 A. In various embodiments, the polymeric composition of a tissue thickness compensator may have a Shore A Hardness value of less than 10 A. In various embodiments, the polymeric composition of a tissue thickness compensator may have a Shore A Hardness value of less than 5 A. In certain embodiments, the polymeric material may have a Shore OO composition value from approximately 35 OO to approximately 75 OO, for example.

[0346] In various embodiments, the polymeric composition may have at least two of the above-identified properties. In various embodiments, the polymeric composition may have at least three of the above-identified properties. The polymeric composition may have a porosity from 85% to 97% by volume, a pore size from 5 micrometers to 2000 micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO, for example. In at least one embodiment, the polymeric composition may comprise 70% by weight of the polymeric composition of PLLA and 30% by weight of the polymeric composition of PCL having a porosity of 90% by volume, a pore size from 100 micrometers to 1000 micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO, for example. In at least one embodiment, the polymeric composition may comprise 65% by weight of the polymeric composition of PGA and 35% by weight of the polymeric composition of PCL having a porosity from 93% to 95% by volume, a pore size from 10 micrometers to 100 micrometers, and a Shore A hardness value from 4 A to 16 A and Shore OO hardness value from 45 OO to 65 OO, for example.

[0347] In various embodiments, the tissue thickness compensator may comprise a material that expands. As discussed above, the tissue thickness compensator may comprise a compressed material that expands when uncompressed or deployed, for example. In various embodiments, the tissue thickness compensator may comprise a self-expanding material formed in situ. In various embodiments, the tissue thickness compensator may comprise at least one precursor selected to spontaneously crosslink when contacted with at least one of other precursor(s), water, and/or bodily fluids. In various embodiments, a first precursor may contact one or more other precursors to form an expandable and/or swellable tissue thickness compensator. In various embodiments, the tissue thickness compensator may comprise a fluid-swellable composition, such as a water-swellable composition, for example. In various embodiments, the tissue thickness compensator may comprise a gel comprising water.

[0348] In various embodiments, the tissue thickness compensator may comprise a biodegradable foam having an encapsulation comprising dry hydrogel particles or granules embedded therein. Without wishing to be bound to any particular theory, the encapsulations in the foam may be formed by contacting an aqueous solution of a hydrogel precursor and an organic solution of biocompatible materials to form the foam. In various embodiments, the aqueous solution and organic solution may form micelles. The aqueous solution and organic solution may be dried to encapsulate dry hydrogel particles or granules within the foam. For example, a hydrogel precursor, such as a hydrophilic polymer, may be dissolved in water to form a dispersion of micelles. The aqueous solution may contact an organic solution of dioxane comprising poly(glycolic acid) and polycaprolactone. The aqueous and organic solutions may be lyophilized to form a biodegradable foam having dry hydrogel particles or granules dispersed therein. Without wishing to be bound to any particular theory, it is believed that the micelles form the encapsulation having the dry hydrogel particles or granules dispersed within the foam structure. In certain embodiments, the encapsulation may be ruptured, and the dry hydrogel particles or granules may contact a fluid, such as a bodily fluid, and expand.

[0349] In various embodiments, as described above, the tissue thickness compensator may comprise an initial thickness and an expanded thickness. In certain embodiments, the initial thickness of a tissue thickness compensator can be approximately 0.001% of its expanded thickness, approximately 0.01% of its expanded thickness, approximately 0.1% of its expanded thickness, approximately 1% of its expanded thickness, approximately 10% of its expanded thickness, approximately 20% of its expanded thickness, approximately 30% of its expanded thickness, approximately 40% of its expanded thickness, approximately 50% of its expanded thickness, approximately 60% of its expanded thickness, approximately 70% of its expanded thickness, approximately 80% of its expanded thickness, and/or approximately 90% of its expanded thickness, for example. In various embodiments, the expanded thickness of the tissue thickness compensator can be approximately two times, approximately five times, approximately ten times, approximately fifty times, approximately one hundred times, approximately two hundred times, approximately three hundred times, approximately four hundred times, approximately five hundred times, approximately six hundred times, approximately seven hundred times, approximately eight hundred times, approximately nine hundred times, and/or approximately one thousand times thicker than its initial thickness, for example. In various embodiments, the initial thickness of the tissue thickness compensator can be up to 1% its expanded thickness, up to 5% its expanded thickness, up to 10% its expanded thickness, and up to 50% its expanded thickness. In various embodiments, the expanded thickness of the tissue thickness compensator can be at least 50% thicker than its initial thickness, at least 100% thicker than its initial thickness, at least 300% thicker than its initial thickness, and at least 500% thicker than its initial thickness. As described above, in various circumstances, as a result of the above, the tissue thickness compensator can be configured to consume any gaps within the staple entrapment area.

[0350] As discussed above, in various embodiments, the tissue thickness compensator may comprise a hydrogel. In various embodiments, the hydrogel may comprise homopolymer hydrogels, copolymer hydrogels, multipolymer hydrogels, interpenetrating polymer hydrogels, and combinations thereof. In various embodiments, the hydrogel may comprise microgels, nanogels, and combinations thereof. The hydrogel may generally comprise a hydrophilic polymer network capable of absorbing and/or retaining fluids. In various embodiments, the hydrogel may comprise a non-crosslinked hydrogel, a crosslinked hydrogel, and combinations thereof. The hydrogel may comprise chemical crosslinks, physical crosslinks, hydrophobic segments and/or water insoluble segments. The hydrogel may be chemically crosslinked by polymerization, small-molecule crosslinking, and/or polymer-polymer crosslinking. The hydrogel may be physically crosslinked by ionic interactions, hydrophobic interactions, hydrogen bonding interactions, sterocomplexation, and/or supramolecular chemistry. The hydrogel may be substantially insoluble due to the crosslinks, hydrophobic segments and/or water insoluble segments, but be expandable and/or swellable due to absorbing and/or retaining fluids. In certain embodiments, the precursor may crosslink with endogenous materials and/or tissues.

[0351] In various embodiments, the hydrogel may comprise an environmentally sensitive hydrogel (ESH). The ESH may comprise materials having fluid-swelling properties that relate to environmental conditions. The environmental conditions may include, but are not limited to, the physical conditions, biological conditions, and/or chemical conditions at the surgical site. In various embodiments, the hydrogel may swell or shrink in response to temperature, pH, electric fields, ionic strength, enzymatic and/or chemical reactions, electrical and/or magnetic stimuli, and other physiological and environmental variables, for example. In various embodiments, the ESH may comprise multifunctional acrylates, hydroxyethylmethacrylate (HEMA), elastomeric acrylates, and related monomers.

[0352] In various embodiments, the tissue thickness compensator comprising a hydrogel may comprise at least one of the non-synthetic materials and synthetic materials described above. The hydrogel may comprise a synthetic hydrogel and/or a non-synthetic hydrogel. In various embodiments, the tissue thickness compensator may comprise a plurality of layers. The plurality of the layers may comprise porous layers and/or non-porous layers. For example, the tissue thickness compensator may comprise a non-porous layer and a porous layer. In another example, the tissue thickness compensator may comprise a porous layer intermediate a first non-porous layer and a second non-porous layer. In another example, the tissue thickness compensator may comprise a non-porous layer intermediate a first porous layer and a second porous layer. The non-porous layers and porous layers may be positioned in any order relative to the surfaces of the staple cartridge and/or anvil.

[0353] Examples of the non-synthetic material may include, but are not limited to, albumin, alginate, carbohydrate, casein, cellulose, chitin, chitosan, collagen, blood, dextran, elastin, fibrin, fibrinogen, gelatin, heparin, hyaluronic acid, keratin, protein, serum, and starch. The cellulose may comprise hydroxyethyl cellulose, oxidized cellulose, oxidized regenerated cellulose (ORC), hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethylcellulose, and combinations thereof. The collagen may comprise bovine pericardium. The carbohydrate may comprise a polysaccharide, such as lyophilized polysaccharide. The protein may comprise glycoprotein, proteoglycan, and combinations thereof.

[0354] Examples of the synthetic material may include, but are not limited to, poly(lactic acid), poly(glycolic acid), poly(hydroxybutyrate), poly(phosphazine), polyesters, polyethylene glycols, polyethylene oxide, polyethylene oxide-co-polypropylene oxide, co-polyethylene oxide, polyalkyleneoxides, polyacrylamides, polyhydroxyethylmethylacrylate, poly(vinylpyrrolidone), polyvinyl alcohols, poly(caprolactone), poly(dioxanone), polyacrylic acid, polyacetate, polypropylene, aliphatic polyesters, glycerols, poly(amino acids), copoly(ether-esters), polyalkylene oxalates, polyamides, poly(iminocarbonates), polyoxaesters, polyorthoesters, polyphosphazenes and combinations thereof. In certain embodiments, the above non-synthetic materials may be synthetically prepared, e.g., synthetic hyaluronic acid, utilizing conventional methods.

[0355] In various embodiments, the hydrogel may be made from one or more hydrogel precursors. The precursor may comprise a monomer and/or a macromer. The hydrogel precursor may comprise an electrophile functional group and/or a nucleophile electrophile functional group. In general, electrophiles may react with nucleophiles to form a bond. The term “functional group” as used herein refers to electrophilic or nucleophilic groups capable of reacting with each other to form a bond. Examples of electrophilic functional groups may include, but are not limited to, N-hydroxysuccinimides (“NHS”), sulfosuccinimides, carbonyldiimidazole, sulfonyl chloride, aryl halides, sulfosuccinimidyl esters, N-hydroxysuccinimidyl esters, succinimidyl esters such as succinimidyl succinates and/or succinimidyl propionates, isocyanates, thiocyanates, carbodiimides, benzotriazole carbonates, epoxides, aldehydes, maleimides, imidoesters, combinations thereof, and the like. In at least one embodiment, the electrophilic functional group may comprise a succinimidyl ester. Examples of nucleophile functional groups may include, but are not limited to, —NH₂, —SH, —OH, —PH₂, and —CO—NH—NH₂.

[0356] In various embodiments, the hydrogel may be formed from a single precursor or multiple precursors. In certain embodiments, the hydrogel may be formed from a first precursor and a second precursor. The first hydrogel precursor and second hydrogel precursor may form a hydrogel in situ and/or in vivo upon contact. The hydrogel precursor may generally refer to a polymer, functional group, macromolecule, small molecule, and/or crosslinker that can take part in a reaction to form a hydrogel. The precursor may comprise a homogeneous solution, heterogeneous, or phase separated solution in a suitable solvent, such as water or a buffer, for example. The buffer may have a pH from about 8 to about 12, such as, about 8.2 to about 9, for example. Examples of buffers may include, but are not limited to borate buffers. In certain embodiments, the precursor(s) may be in an emulsion. In various embodiments, a first precursor may react with a second precursor to form a hydrogel. In various embodiments, the first precursor may spontaneously crosslink when contacted with the second precursor. In various embodiments, a first set of electrophilic functional groups on a first precursor may react with a second set of nucleophilic functional groups on a second precursor. When the precursors are mixed in an environment that permits reaction (e.g., as relating to pH, temperature, and/or solvent), the functional groups may react with each other to form covalent bonds. The precursors may become crosslinked when at least some of the precursors react with more than one other precursor.

[0357] In various embodiments, the tissue thickness compensator may comprise at least one monomer selected from the group consisting of 3-sulfopropyl acrylate potassium salt (“KSPA”), sodium acrylate (“NaA”), N-(tris(hydroxylmethyl)methyl)acrylamide (“tris acryl”), and 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS). The tissue thickness compensator may comprise a copolymer comprising two or more monomers selected from the group consisting of KSPA, NaA, tris acryl, AMPS. The tissue thickness compensator may comprise homopolymers derived from KSPA, NaA, trisacryl and AMPS. The tissue thickness compensator may comprise hydrophilicity modifying monomers copolymerizable therewith. The hydrophilicity modifying monomers may comprise methylmethacrylate, butylacrylate, cyclohexylacrylate, styrene, styrene sulphonic acid.

[0358] In various embodiments, the tissue thickness compensator may comprise a crosslinker. The crosslinker may comprise a low molecular weight di- or polyvinylic crosslinking agent, such as ethylenglycol diacrylate or dimethacrylate, di-, tri- or tetraethylen-glycol diacrylate or dimethacrylate, allyl(meth)acrylate, a C₂-C₈-alkylene diacrylate or dimethacrylate, divinyl ether, divinyl sulfone, di- and trivinylbenzene, trimethylolpropane triacrylate or trimethacrylate, pentaerythritol tetraacrylate or tetramethacrylate, bisphenol A diacrylate or dimethacrylate, methylene bisacrylamide or bismethacrylamide, ethylene bisacrylamide or ethylene bismethacrylamide, triallyl phthalate or diallyl phthalate. In at least one embodiment, the crosslinker may comprise N,N′-methylenebisacrylamide (“MBAA”).

[0359] In various embodiments, the tissue thickness compensator may comprise at least one of acrylate and/or methacrylate functional hydrogels, biocompatible photoinitiator, alkyl-cyanoacrylates, isocyanate functional macromers, optionally comprising amine functional macromers, succinimidyl ester functional macromers, optionally comprising amine and/or sulfhydryl functional macromers, epoxy functional macromers, optionally comprising amine functional macromers, mixtures of proteins and/or polypeptides and aldehyde crosslinkers, Genipin, and water-soluble carbodiimides, anionic polysaccharides and polyvalent cations.

[0360] In various embodiments, the tissue thickness compensator may comprise unsaturated organic acid monomers, acrylic substituted alcohols, and/or acrylamides. In various embodiments, the tissue thickness compensator may comprise methacrylic acids, acrylic acids, glycerolacrylate, glycerolmethacryulate, 2-hydroxyethylmethacrylate, 2-hydroxyethylacrylate, 2-(dimethylaminoethyl)methacrylate, N-vinyl pyrrolidone, methacrylamide, and/or N,N-dimethylacrylamide poly(methacrylic acid).

[0361] In various embodiments, the tissue thickness compensator may comprise a reinforcement material. In various embodiments, the reinforcement material may comprise at least one of the non-synthetic materials and synthetic materials described above. In various embodiments, the reinforcement material may comprise collagen, gelatin, fibrin, fibrinogen, elastin, keratin, albumin, hydroxyethyl cellulose, cellulose, oxidized cellulose, hydroxypropyl cellulose, carboxyethyl cellulose, carboxymethylcellulose, chitan, chitosan, alginate, poly(lactic acid), poly(glycolic acid), poly(hydroxybutyrate), poly(phosphazine), polyesters, polyethylene glycols, polyalkyleneoxides, polyacrylamides, polyhydroxyethylmethylacrylate, polyvinylpyrrolidone, polyvinyl alcohols, poly(caprolactone), poly(dioxanone), polyacrylic acid, polyacetate, polycaprolactone, polypropylene, aliphatic polyesters, glycerols, poly(amino acids), copoly(ether-esters), polyalkylene oxalates, polyamides, poly(iminocarbonates), polyalkylene oxalates, polyoxaesters, polyorthoesters, polyphosphazenes and combinations thereof.

[0362] In various embodiments, the tissue thickness compensator may comprise a layer comprising the reinforcement material. In certain embodiments, a porous layer and/or a non-porous layer of a tissue thickness compensator may comprise the reinforcement material. For example, the porous layer may comprise the reinforcement material and the non-porous layer may not comprise the reinforcement material. In various embodiments, the reinforcement layer may comprise an inner layer intermediate a first non-porous layer and a second non-porous layer. In certain embodiments, the reinforcement layer may comprise an outer layer of the tissue thickness compensator. In certain embodiments, the reinforcement layer may comprise an exterior surface of the tissue thickness compensator.

[0363] In various embodiments, the reinforcement material may comprise meshes, monofilaments, multifilament braids, fibers, mats, felts, particles, and/or powders. In certain embodiments, the reinforcement material may be incorporated into a layer of the tissue thickness compensator. The reinforcement material may be incorporated into at least one of a non-porous layer and a porous layer. A mesh comprising the reinforcement material may be formed using conventional techniques, such as, for example, knitting, weaving, tatting, and/or knipling. In various embodiments, a plurality of reinforcement materials may be oriented in a random direction and/or a common direction. In certain embodiments, the common direction may be one of parallel to the staple line and perpendicular to the staple line, for example. For example, the monofilaments and/or multifilament braids may be oriented in a random direction and/or a common direction. The monofilaments and multifilament braids may be associated with the non-porous layer and/or the porous layer. In various embodiments, the tissue thickness compensator may comprise a plurality of reinforcement fibers oriented in a random direction within a non-porous layer. In various embodiments, the tissue thickness compensator may comprise a plurality of reinforcement fibers oriented in a common direction within a non-porous layer.

[0364] The fibers may form a non-woven material, such as, for example, a mat and a felt. The fibers may have any suitable length, such as, for example from 0.1 mm to 100 mm and 0.4 mm to 50 mm. The reinforcement material may be ground to a powder. The powder may have a particle size from 10 micrometers to 1 cm, for example. The powder may be incorporated into the tissue thickness compensator.

[0365] In various embodiments, the tissue thickness compensator may be formed in situ. In various embodiments, the hydrogel may be formed in situ. The tissue thickness compensator may be formed in situ by covalent, ionic, and/or hydrophobic bonds. Physical (non-covalent) crosslinks may result from complexation, hydrogen bonding, desolvation, Van der Waals interactions, ionic bonding, and combinations thereof. Chemical (covalent) crosslinking may be accomplished by any of a number of mechanisms, including: free radical polymerization, condensation polymerization, anionic or cationic polymerization, step growth polymerization, electrophile-nucleophile reactions, and combinations thereof.

[0366] In various embodiments, in situ formation of the tissue thickness compensator may comprise reacting two or more precursors that are physically separated until contacted in situ and/or react to an environmental condition to react with each other to form the hydrogel. In situ polymerizable polymers may be prepared from precursor(s) that can be reacted to form a polymer at the surgical site. The tissue thickness compensator may be formed by crosslinking reactions of the precursor(s) in situ. In certain embodiments, the precursor may comprise an initiator capable of initiating a polymerization reaction for the formation of the in situ tissue thickness compensator. The tissue thickness compensator may comprise a precursor that can be activated at the time of application to create, in various embodiments, a crosslinked hydrogel. In situ formation of the tissue thickness compensator may comprise activating at least one precursor to form bonds to form the tissue thickness compensator. In various embodiments, activation may be achieved by changes in the physical conditions, biological conditions, and/or chemical conditions at the surgical site, including, but not limited to temperature, pH, electric fields, ionic strength, enzymatic and/or chemical reactions, electrical and/or magnetic stimuli, and other physiological and environmental variables. In various embodiments, the precursors may be contacted outside the body and introduced to the surgical site.

[0367] In various embodiments, the tissue thickness compensator may comprise one or more encapsulations, or cells, which can be configured to store at least one component therein. In certain embodiments, the encapsulation may be configured to store a hydrogel precursor therein. In certain embodiments, the encapsulation may be configured to store two components therein, for example. In certain embodiments, the encapsulation may be configured to store a first hydrogel precursor and a second hydrogel precursor therein. In certain embodiments, a first encapsulation may be configured to store a first hydrogel precursor therein and a second encapsulation may be configured to store a second hydrogel precursor therein. As described above, the encapsulations can be aligned, or at least substantially aligned, with the staple legs to puncture and/or otherwise rupture the encapsulations when the staple legs contact the encapsulation. In certain embodiments, the encapsulations may be compressed, crushed, collapsed, and/or otherwise ruptured when the staples are deployed. After the encapsulations have been ruptured, the component(s) stored therein can flow out of the encapsulation. The component stored therein may contact other components, layers of the tissue thickness compensator, and/or the tissue. In various embodiments, the other components may be flowing from the same or different encapsulations, provided in the layers of the tissue thickness compensator, and/or provided to the surgical site by the clinician. As a result of the above, the component(s) stored within the encapsulations can provide expansion and/or swelling of the tissue thickness compensator.

[0368] In various embodiments, the tissue thickness compensator may comprise a layer comprising the encapsulations. In various embodiments, the encapsulation may comprise a void, a pocket, a dome, a tube, and combinations thereof associated with the layer. In certain embodiments, the encapsulations may comprise voids in the layer. In at least one embodiment, the layer can comprise two layers that can be attached to one another wherein the encapsulations can be defined between the two layers. In certain embodiments, the encapsulations may comprise domes on the surface of the layer. For example, at least a portion of the encapsulations can be positioned within domes extending upwardly from the layer. In certain embodiments, the encapsulations may comprise pockets formed within the layer. In certain embodiments, a first portion of the encapsulations may comprise a dome and a second portion of the encapsulations may comprise a pocket. In certain embodiments, the encapsulations may comprise a tube embedded within the layer. In certain embodiments, the tube may comprise the non-synthetic materials and/or synthetic materials described herein, such as PLA. In at least one embodiment, the tissue thickness compensator may comprise a bioabsorable foam, such as ORC, comprising PLA tubes embedded therein, and the tube may encapsulate a hydrogel, for example. In certain embodiments, the encapsulations may comprise discrete cells that are unconnected to each other. In certain embodiments, one or more of the encapsulations can be in fluid communication with each other via one or more passageways, conduits, and/or channels, for example, extending through the layer.

[0369] The rate of release of a component from the encapsulation may be controlled by the thickness of the tissue thickness compensator, the composition of tissue thickness compensator, the size of the component, the hydrophilicity of the component, and/or the physical and/or chemical interactions among the component, the composition of the tissue thickness compensator, and/or the surgical instrument, for example. In various embodiments, the layer can comprise one or more thin sections or weakened portions, such as partial perforations, for example, which can facilitate the incision of the layer and the rupture of the encapsulations. In various embodiments, the partial perforations may not completely extend through a layer while, in certain embodiments, perforations may completely extend through the layer.

[0370] In various embodiments, an anvil may comprise a tissue thickness compensator comprising an encapsulated component comprising at least one microsphere particle. In certain embodiments, the tissue thickness compensator may comprise an encapsulation comprising a first encapsulated component and a second encapsulated component. In certain embodiments, the tissue thickness compensator may comprise an encapsulation comprising a first microsphere particle and a second microsphere particle.

[0371] In various embodiments, the tissue thickness compensator may be suitable for use with a surgical instrument. As described above the tissue thickness compensator may be associated with the staple cartridge and/or the anvil. The tissue thickness compensator may be configured into any shape, size and/or dimension suitable to fit the staple cartridge and/or anvil. As described herein, the tissue thickness compensator may be releasably attached to the staple cartridge and/or anvil. The tissue thickness compensator may be attached to the staple cartridge and/or anvil in any mechanical and/or chemical manner capable of retaining the tissue thickness compensator in contact with the staple cartridge and/or anvil prior to and during the stapling process. The tissue thickness compensator may be removed or released from the staple cartridge and/or anvil after the staple penetrates the tissue thickness compensator. The tissue thickness compensator may be removed or released from the staple cartridge and/or anvil as the staple cartridge and/or anvil is moved away from the tissue thickness compensator.

[0372] In various embodiments, referring now to FIG. 14, a staple cartridge, such as staple cartridge 10000, for example, can comprise a support portion 10010 and a compressible tissue thickness compensator 10020. Referring now to FIGS. 16-18, the support portion 10010 can comprise a deck surface 10011 and a plurality of staple cavities 10012 defined within the support portion 10010. Each staple cavity 10012 can be sized and configured to removably store a staple, such as a staple 10030, for example, therein. The staple cartridge 10000 can further comprise a plurality of staple drivers 10040 which can each be configured to support one or more staples 10030 within the staple cavities 10012 when the staples 10030 and the staple drivers 10040 are in their unfired positions. In at least one such embodiment, referring primarily to FIGS. 22 and 23, each staple driver 10040 can comprise one or more cradles, or troughs, 10041, for example, which can be configured to support the staples and limit relative movement between the staples 10030 and the staple drivers 10040. In various embodiments, referring again to FIG. 16, the staple cartridge 10000 can further comprise a staple-firing sled 10050 which can be moved from a proximal end 10001 to a distal end 10002 of the staple cartridge in order to sequentially lift the staple drivers 10040 and the staples 10030 from their unfired positions toward an anvil positioned opposite the staple cartridge 10000. In certain embodiments, referring primarily to FIGS. 16 and 18, each staple 10030 can comprise a base 10031 and one or more legs 10032 extending from the base 10031 wherein each staple can be at least one of substantially U-shaped and substantially V-shaped, for example. In at least one embodiment, the staples 10030 can be configured such that the tips of the staple legs 10032 are recessed with respect to the deck surface 10011 of the support portion 10010 when the staples 10030 are in their unfired positions. In at least one embodiment, the staples 10030 can be configured such that the tips of the staple legs 10032 are flush with respect to the deck surface 10011 of the support portion 10010 when the staples 10030 are in their unfired positions. In at least one embodiment, the staples 10030 can be configured such that the tips of the staple legs 10032, or at least some portion of the staple legs 10032, extend above the deck surface 10011 of the support portion 10010 when the staples 10030 are in their unfired positions. In such embodiments, the staple legs 10032 can extend into and can be embedded within the tissue thickness compensator 10020 when the staples 10030 are in their unfired positions. In at least one such embodiment, the staple legs 10032 can extend above the deck surface 10011 by approximately 0.075″, for example. In various embodiments, the staple legs 10032 can extend above the deck surface 10011 by a distance between approximately 0.025″ and approximately 0.125″, for example. In certain embodiments, further to the above, the tissue thickness compensator 10020 can comprise an uncompressed thickness between approximately 0.08″ and approximately 0.125″, for example.

[0373] In use, further to the above and referring primarily to FIG. 31, an anvil, such as anvil, 10060, for example, can be moved into a closed position opposite the staple cartridge 10000. As described in greater detail below, the anvil 10060 can position tissue against the tissue thickness compensator 10020 and, in various embodiments, compress the tissue thickness compensator 10020 against the deck surface 10011 of the support portion 10010, for example. Once the anvil 10060 has been suitably positioned, the staples 10030 can be deployed, as also illustrated in FIG. 31. In various embodiments, as mentioned above, the staple-firing sled 10050 can be moved from the proximal end 10001 of the staple cartridge 10000 toward the distal end 10002, as illustrated in FIG. 32. As the sled 10050 is advanced, the sled 10050 can contact the staple drivers 10040 and lift the staple drivers 10040 upwardly within the staple cavities 10012. In at least one embodiment, the sled 10050 and the staple drivers 10040 can each comprise one or more ramps, or inclined surfaces, which can co-operate to move the staple drivers 10040 upwardly from their unfired positions. In at least one such embodiment, referring to FIGS. 19-23, each staple driver 10040 can comprise at least one inclined surface 10042 and the sled 10050 can comprise one or more inclined surfaces 10052 which can be configured such that the inclined surfaces 10052 can slide under the inclined surface 10042 as the sled 10050 is advanced distally within the staple cartridge. As the staple drivers 10040 are lifted upwardly within their respective staple cavities 10012, the staple drivers 10040 can lift the staples 10030 upwardly such that the staples 10030 can emerge from their staple cavities 10012 through openings in the staple deck 10011. During an exemplary firing sequence, referring primarily to FIGS. 25-27, the sled 10050 can first contact staple 10030a and begin to lift the staple 10030a upwardly. As the sled 10050 is advanced further distally, the sled 10050 can begin to lift staples 10030b, 10030c, 10030d, 10030e, and 10030f, and any other subsequent staples, in a sequential order. As illustrated in FIG. 27, the sled 10050 can drive the staples 10030 upwardly such that the legs 10032 of the staples contact the opposing anvil, are deformed to a desired shape, and ejected therefrom the support portion 10010. In various circumstances, the sled 10030 can move several staples upwardly at the same time as part of a firing sequence. With regard to the firing sequence illustrated in FIG. 27, the staples 10030a and 10030b have been moved into their fully fired positions and ejected from the support portion 10010, the staples 10030c and 10030d are in the process of being fired and are at least partially contained within the support portion 10010, and the staples 10030e and 10030f are still in their unfired positions.

[0374] As discussed above, and referring to FIG. 33, the staple legs 10032 of the staples 10030 can extend above the deck surface 10011 of the support portion 10010 when the staples 10030 are in their unfired positions. With further regard to this firing sequence illustrated in FIG. 27, the staples 10030e and 10030f are illustrated in their unfired position and their staple legs 10032 extend above the deck surface 10011 and into the tissue thickness compensator 10020. In various embodiments, the tips of the staple legs 10032, or any other portion of the staple legs 10032, may not protrude through a top tissue-contacting surface 10021 of the tissue thickness compensator 10020 when the staples 10030 are in their unfired positions. As the staples 10030 are moved from their unfired positions to their fired positions, as illustrated in FIG. 27, the tips of the staple legs can protrude through the tissue-contacting surface 10032. In various embodiments, the tips of the staple legs 10032 can comprise sharp tips which can incise and penetrate the tissue thickness compensator 10020. In certain embodiments, the tissue thickness compensator 10020 can comprise a plurality of apertures which can be configured to receive the staple legs 10032 and allow the staple legs 10032 to slide relative to the tissue thickness compensator 10020. In certain embodiments, the support portion 10010 can further comprise a plurality of guides 10013 extending from the deck surface 10011. The guides 10013 can be positioned adjacent to the staple cavity openings in the deck surface 10011 such that the staple legs 10032 can be at least partially supported by the guides 10013. In certain embodiments, a guide 10013 can be positioned at a proximal end and/or a distal end of a staple cavity opening. In various embodiments, a first guide 10013 can be positioned at a first end of each staple cavity opening and a second guide 10013 can be positioned at a second end of each staple cavity opening such that each first guide 10013 can support a first staple leg 10032 of a staple 10030 and each second guide 10013 can support a second staple leg 10032 of the staple. In at least one embodiment, referring to FIG. 33, each guide 10013 can comprise a groove or slot, such as groove 10016, for example, within which a staple leg 10032 can be slidably received. In various embodiments, each guide 10013 can comprise a cleat, protrusion, and/or spike that can extend from the deck surface 10011 and can extend into the tissue thickness compensator 10020. In at least one embodiment, as discussed in greater detail below, the cleats, protrusions, and/or spikes can reduce relative movement between the tissue thickness compensator 10020 and the support portion 10010. In certain embodiments, the tips of the staple legs 10032 may be positioned within the guides 10013 and may not extend above the top surfaces of the guides 10013 when the staples 10030 are in their unfired position. In at least such embodiment, the guides 10013 can define a guide height and the staples 10030 may not extend above this guide height when they are in their unfired position.

[0375] In various embodiments, a tissue thickness compensator, such as tissue thickness compensator 10020, for example, can be comprised of a single sheet of material. In at least one embodiment, a tissue thickness compensator can comprise a continuous sheet of material which can cover the entire top deck surface 10011 of the support portion 10010 or, alternatively, cover less than the entire deck surface 10011. In certain embodiments, the sheet of material can cover the staple cavity openings in the support portion 10010 while, in other embodiments, the sheet of material can comprise openings which can be aligned, or at least partially aligned, with the staple cavity openings. In various embodiments, a tissue thickness compensator can be comprised of multiple layers of material. In some embodiments, referring now to FIG. 15, a tissue thickness compensator can comprise a compressible core and a wrap surrounding the compressible core. In certain embodiments, a wrap 10022 can be configured to releasably hold the compressible core to the support portion 10010. In at least one such embodiment, the support portion 10010 can comprise one or more projections, such as projections 10014 (FIG. 18), for example, extending therefrom which can be received within one or more apertures and/or slots, such as apertures 10024, for example, defined in the wrap 10022. The projections 10014 and the apertures 10024 can be configured such that the projections 10014 can retain the wrap 10022 to the support portion 10010. In at least one embodiment, the ends of the projections 10014 can be deformed, such as by a heat-stake process, for example, in order to enlarge the ends of the projections 10014 and, as a result, limit the relative movement between the wrap 10022 and the support portion 10010. In at least one embodiment, the wrap 10022 can comprise one or more perforations 10025 which can facilitate the release of the wrap 10022 from the support portion 10010, as illustrated in FIG. 15. Referring now to FIG. 24, a tissue thickness compensator can comprise a wrap 10222 including a plurality of apertures 10223, wherein the apertures 10223 can be aligned, or at least partially aligned, with the staple cavity openings in the support portion 10010. In certain embodiments, the core of the tissue thickness compensator can also comprise apertures which are aligned, or at least partially aligned, with the apertures 10223 in the wrap 10222. In other embodiments, the core of the tissue thickness compensator can comprise a continuous body and can extend underneath the apertures 10223 such that the continuous body covers the staple cavity openings in the deck surface 10011.

[0376] In various embodiments, as described above, a tissue thickness compensator can comprise a wrap for releasably holding a compressible core to the support portion 10010. In at least one such embodiment, referring to FIG. 16, a staple cartridge can further comprise retainer clips 10026 which can be configured to inhibit the wrap, and the compressible core, from prematurely detaching from the support portion 10010. In various embodiments, each retainer clip 10026 can comprise apertures 10028 which can be configured to receive the projections 10014 extending from the support portion 10010 such that the retainer clips 10026 can be retained to the support portion 10010. In certain embodiments, the retainer clips 10026 can each comprise at least one pan portion 10027 which can extend underneath the support portion 10010 and can support and retain the staple drivers 10040 within the support portion 10010. In certain embodiments, as described above, a tissue thickness compensator can be removably attached to the support portion 10010 by the staples 10030. More particularly, as also described above, the legs of the staples 10030 can extend into the tissue thickness compensator 10020 when the staples 10030 are in their unfired position and, as a result, releasably hold the tissue thickness compensator 10020 to the support portion 10010. In at least one embodiment, the legs of the staples 10030 can be in contact with the sidewalls of their respective staple cavities 10012 wherein, owing to friction between the staple legs 10032 and the sidewalls, the staples 10030 and the tissue thickness compensator 10020 can be retained in position until the staples 10030 are deployed from the staple cartridge 10000. When the staples 10030 are deployed, the tissue thickness compensator 10020 can be captured within the staples 10030 and held against the stapled tissue T. When the anvil is thereafter moved into an open position to release the tissue T, the support portion 10010 can be moved away from the tissue thickness compensator 10020 which has been fastened to the tissue. In certain embodiments, an adhesive can be utilized to removably hold the tissue thickness compensator 10020 to the support portion 10010. In at least one embodiment, a two-part adhesive can be utilized wherein, in at least one embodiment, a first part of the adhesive can be placed on the deck surface 10011 and a second part of the adhesive can be placed on the tissue thickness compensator 10020 such that, when the tissue thickness compensator 10020 is placed against the deck surface 10011, the first part can contact the second part to active the adhesive and detachably bond the tissue thickness compensator 10020 to the support portion 10010. In various embodiments, any other suitable means could be used to detachably retain the tissue thickness compensator to the support portion of a staple cartridge.

[0377] In various embodiments, further to the above, the sled 10050 can be advanced from the proximal end 10001 to the distal end 10002 to fully deploy all of the staples 10030 contained within the staple cartridge 10000. In at least one embodiment, referring now to FIGS. 56-60, the sled 10050 can be advanced distally within a longitudinal cavity 10016 within the support portion 10010 by a firing member, or knife bar, 10052 of a surgical stapler. In use, the staple cartridge 10000 can be inserted into a staple cartridge channel in a jaw of the surgical stapler, such as staple cartridge channel 10070, for example, and the firing member 10052 can be advanced into contact with the sled 10050, as illustrated in FIG. 56. As the sled 10050 is advanced distally by the firing member 10052, the sled 10050 can contact the proximal-most staple driver, or drivers, 10040 and fire, or eject, the staples 10030 from the cartridge body 10010, as described above. As illustrated in FIG. 56, the firing member 10052 can further comprise a cutting edge 10053 which can be advanced distally through a knife slot in the support portion 10010 as the staples 10030 are being fired. In various embodiments, a corresponding knife slot can extend through the anvil positioned opposite the staple cartridge 10000 such that, in at least one embodiment, the cutting edge 10053 can extend between the anvil and the support portion 10010 and incise the tissue and the tissue thickness compensator positioned therebetween. In various circumstances, the sled 10050 can be advanced distally by the firing member 10052 until the sled 10050 reaches the distal end 10002 of the staple cartridge 10000, as illustrated in FIG. 58. At such point, the firing member 10052 can be retracted proximally. In some embodiments, the sled 10050 can be retracted proximally with the firing member 10052 but, in various embodiments, referring now to FIG. 59, the sled 10050 can be left behind in the distal end 10002 of the staple cartridge 10000 when the firing member 10052 is retracted. Once the firing member 10052 has been sufficiently retracted, the anvil can be re-opened, the tissue thickness compensator 10020 can be detached from the support portion 10010, and the remaining non-implanted portion of the expended staple cartridge 10000, including the support portion 10010, can be removed from the staple cartridge channel 10070.

[0378] After the expended staple cartridge 10000 has been removed from the staple cartridge channel, further to the above, a new staple cartridge 10000, or any other suitable staple cartridge, can be inserted into the staple cartridge channel 10070. In various embodiments, further to the above, the staple cartridge channel 10070, the firing member 10052, and/or the staple cartridge 10000 can comprise co-operating features which can prevent the firing member 10052 from being advanced distally a second, or subsequent, time without a new, or unfired, staple cartridge 10000 positioned in the staple cartridge channel 10070. More particularly, referring again to FIG. 56, as the firing member 10052 is advanced into contact with the sled 10050 and, when the sled 10050 is in its proximal unfired position, a support nose 10055 of the firing member 10052 can be positioned on and/or over a support ledge 10056 on the sled 10050 such that the firing member 10052 is held in a sufficient upward position to prevent a lock, or beam, 10054 extending from the firing member 10052 from dropping into a lock recess defined within the staple cartridge channel. As the lock 10054 will not drop into the lock recess, in such circumstances, the lock 10054 may not abut a distal sidewall 10057 of the lock recess as the firing member 10052 is advanced. As the firing member 10052 pushes the sled 10050 distally, the firing member 10052 can be supported in its upward firing position owing to the support nose 10055 resting on the support ledge 10056. When the firing member 10052 is retracted relative to the sled 10050, as discussed above and illustrated in FIG. 59, the firing member 10052 can drop downwardly from its upward position as the support nose 10055 is no longer resting on the support ledge 10056 of the sled 10050. In at least one such embodiment, the surgical staple can comprise a spring 10058, and/or any other suitable biasing element, which can be configured to bias the firing member 10052 into its downward position. Once the firing member 10052 has been completely retracted, as illustrated in FIG. 60, the firing member 10052 cannot be advanced distally through the spent staple cartridge 10000 once again. More particularly, the firing member 10052 can't be held in its upper position by the sled 10050 as the sled 10050, at this point in the operating sequence, has been left behind at the distal end 10002 of the staple cartridge 10000. Thus, as mentioned above, in the event that the firing member 10052 is advanced once again without replacing the staple cartridge, the lock beam 10054 will contact the sidewall 10057 of the lock recess which will prevent the firing member 10052 from being advanced distally into the staple cartridge 10000 once again. Stated another way, once the spent staple cartridge 10000 has been replaced with a new staple cartridge, the new staple cartridge will have a proximally-positioned sled 10050 which can hold the firing member 10052 in its upper position and allow the firing member 10052 to be advanced distally once again.

[0379] As described above, the sled 10050 can be configured to move the staple drivers 10040 between a first, unfired position and a second, fired position in order to eject staples 10030 from the support portion 10010. In various embodiments, the staple drivers 10040 can be contained within the staple cavities 10012 after the staples 10030 have been ejected from the support portion 10010. In certain embodiments, the support portion 10010 can comprise one or more retention features which can be configured to block the staple drivers 10040 from being ejected from, or falling out of, the staple cavities 10012. In various other embodiments, the sled 10050 can be configured to eject the staple drivers 10040 from the support portion 10010 with the staples 10030. In at least one such embodiment, the staple drivers 10040 can be comprised of a bioabsorbable and/or biocompatible material, such as Ultem, for example. In certain embodiments, the staple drivers can be attached to the staples 10030. In at least one such embodiment, a staple driver can be molded over and/or around the base of each staple 10030 such that the driver is integrally formed with the staple. U.S. patent application Ser. No. 11/541,123, entitled SURGICAL STAPLES HAVING COMPRESSIBLE OR CRUSHABLE MEMBERS FOR SECURING TISSUE THEREIN AND STAPLING INSTRUMENTS FOR DEPLOYING THE SAME, filed on Sep. 29, 2006, now U.S. Pat. No. 7,794,475, which issued on Sep. 14, 2010, is hereby incorporated by reference in its entirety.

[0380] As described above, a surgical stapling instrument can comprise a staple cartridge channel configured to receive a staple cartridge, an anvil rotatably coupled to the staple cartridge channel, and a firing member comprising a knife edge which is movable relative to the anvil and the staple cartridge channel. In use, a staple cartridge can be positioned within the staple cartridge channel and, after the staple cartridge has been at least partially expended, the staple cartridge can be removed from the staple cartridge channel and replaced with a new staple cartridge. In some such embodiments, the staple cartridge channel, the anvil, and/or the firing member of the surgical stapling instrument may be re-used with the replacement staple cartridge. In certain other embodiments, a staple cartridge may comprise a part of a disposable loading unit assembly which can include a staple cartridge channel, an anvil, and/or a firing member, for example, which can be replaced along with the staple cartridge as part of replacing the disposable loading unit assembly. Certain disposable loading unit assemblies are disclosed in U.S. patent application Ser. No. 12/031,817, entitled END EFFECTOR COUPLING ARRANGEMENTS FOR A SURGICAL CUTTING AND STAPLING INSTRUMENT, which was filed on Feb. 15, 2008, the entire disclosure of which is incorporated by reference herein.

[0381] In various embodiments, the tissue thickness compensator may comprise an extrudable, a castable, and/or moldable composition comprising at least one of the synthetic and/or non-synthetic materials described herein. In various embodiments, the tissue thickness compensator may comprise a film or sheet comprising two or more layers. The tissue thickness compensator may be obtained using conventional methods, such as, for example, mixing, blending, compounding, spraying, wicking, solvent evaporating, dipping, brushing, vapor deposition, extruding, calendaring, casting, molding and the like. In extrusion, an opening may be in the form of a die comprising at least one opening to impart a shape to the emerging extrudate. In calendering, an opening may comprise a nip between two rolls. Conventional molding methods may include, but are not limited to, blow molding, injection molding, foam injection, compression molding, thermoforming, extrusion, foam extrusion, film blowing, calendaring, spinning, solvent welding, coating methods, such as dip coating and spin coating, solution casting and film casting, plastisol processing (including knife coating, roller coating and casting), and combinations thereof. In injection molding, an opening may comprise a nozzle and/or channels/runners and/or mold cavities and features. In compression molding, the composition may be positioned in a mold cavity, heated to a suitable temperature, and shaped by exposure to compression under relatively high pressure. In casting, the composition may comprise a liquid or slurry that may be poured or otherwise provided into, onto and/or around a mold or object to replicate features of the mold or object. After casting, the composition may be dried, cooled, and/or cured to form a solid.

[0382] In various embodiments, a method of manufacturing a tissue thickness compensator comprising at least one medicament stored and/or absorbed therein may generally comprise providing a tissue thickness compensator and contacting the tissue thickness compensator and the medicament to retain the medicament in the tissue thickness compensator. In at least one embodiment, a method of manufacturing a tissue thickness compensator comprising an antibacterial material may comprise providing a hydrogel, drying the hydrogel, swelling the hydrogel in an aqueous solution of silver nitrate, contacting the hydrogel and a solution of sodium chloride to form the tissue thickness compensator having antibacterial properties. The tissue thickness compensator may comprise silver dispersed therein.

[0383] In various embodiments, referring now to FIG. 71, a tissue thickness compensator 21020 can comprise a compensator body 21022 and a plurality of capsules, or tubes, 21024 positioned therein. In at least one embodiment, each of the tubes 21024 can include a cavity 21026 defined therein which can include one or more medicaments therein. As described in greater detail below, the tissue thickness compensator 21020 can be manufactured by placing the tubes 21024 in a mold, for example, and forming the compensator body 21022 around the tubes 21024. In certain embodiments, the one or medicaments can be placed in the tubes 21024 before the tubes 21024 are placed in the mold such that, after the compensator body 21022 has solidified, lyophilized, and/or cured, for example, the tubes 21024 can be encapsulated in the compensator body 21022. In other embodiments, referring now to FIG. 72, a tissue thickness compensator 21120 can comprise a plurality of capsules, or tubes, 21124 positioned within a compensator body 21122 wherein one or more medicaments can be loaded into the tubes 21124 after the compensator body 21122 has been formed around the tubes 21124. In at least one such embodiment, the tissue thickness compensator 21120 can comprise a port 21123 which can be in fluid communication with the tubes 21124 and can be configured to permit the one or medicaments to be injected into the tubes 21124 utilizing a syringe 21125, for example. In some circumstances, a surgeon, or other clinician, can load the one or more medicaments into the tubes 21124 just before the tissue thickness compensator 21120 is inserted into the patient. Such embodiments may be especially useful when the tissue thickness compensator 21120 may be expected to, or required to, have a long storage duration, or shelf-life.

[0384] In various embodiments, referring now to FIG. 73, the compensator body 21022 of the tissue thickness compensator 21020 can be comprised of a bioabsorbable material, for example. In at least one embodiment, the compensator body 21022 can be comprised of any suitable material, such as PGA and/or PCL, for example. In certain embodiments, the tubes 21024 can be comprised of any suitable of a bioabsorbable material, for example. In at least one embodiment, the tubes 21024 can be comprised of any suitable material, such as hyaluronic acid, gelatin, PDS, and/or oxidized regenerated cellulose (ORC), for example. In at least one embodiment, the one or medicaments 21025 contained within the cavity 21026 can comprise a fluid, such as, doxycycline, for example. In at least one such embodiment, each of the tubes 21024 can be sealed such that the medicaments 21025 can be stored within the tubes 21024 until at least a portion of the tubes 21024 have been dissolved and/or bioabsorbed, for example. In use, referring now to FIG. 74, the tubes 21024 can be exposed to a bodily fluid, such as blood, for example, which can come into contact with and dissolve the tubes 21024. In at least one embodiment, referring to FIG. 75, the bodily fluid can be expressed from tissue T when the tissue T and the tissue thickness compensator 21020 are compressed by an anvil 21060 and/or a plurality of staples 21030, for example. In various embodiments, a bioabsorbable wrap can be utilized to enclose, or at least partially enclose, the compensator body 21022. In at least one such embodiment, the wrap can be comprised of hyaluronic acid and/or ORC, for example.

[0385] In various embodiments, referring now to FIG. 77, a capsule, or tube, 21224 can comprise a plurality of layers 21224a-21224d, for example. In at least one embodiment, each tube 21224 can comprise an outer, or first, layer 21224a, a second layer 21224b, a third layer 21224c, and an inner layer 21224d, for example. In various embodiments, the outer layer 21224a can be comprised of a haemostatic material, such as thrombin, for example. The second layer 21224b can be comprised of an anti-microbial and/or anti-biotic material, such as doxycycline and/or gentamicin, for example. The third layer 21224c can be comprised of an anti-inflammatory material, such as diclofenac and/or NSAIDSs, for example. The inner layer 21224d can be comprised of a healing influencing material, such as a powdered collageno synthetic material, for example. Referring again to FIG. 77, the tube 21224 can be structured and arranged such that the outer layer 21224a is dissolved, or at least substantially dissolved, before the second layer 21224b is dissolved, or at least partially dissolved. In various embodiments, referring to FIG. 76, the outer layer 21224a can begin dissolve as soon as it is exposed to a bodily fluid. This moment in time is indicated as time to. In certain embodiments, the outer layer 21224a can be completely dissolved over the course of minutes, hours, and/or days wherein the material comprising the outer layer 21224a can reach a maximum efficacy or concentration at a moment in time indicated as time t1. At some later moment in time, the outer layer 21224a can be completely, or at least substantially, dissolved by a moment in time indicated by time t2.

[0386] As the outer layer 21224a is being dissolved, the bodily fluid can reach the second layer 21224b and begin to at least partially dissolve the second layer 21224b. Similar to the above, the second layer 21224b can be completely dissolved over the course of minutes, hours, and/or days wherein the material comprising the second layer 21224b can reach a maximum efficacy or concentration at a moment in time indicated as time t3. In various circumstances, a bodily fluid can pass through the outer layer 21224a to reach the second layer 21224b such that the outer layer 21224a and the second layer 21224b can begin to dissolve at the same, or at least substantially the same, time. In any event, the reader will note that the time t1 in which the material comprising the outer layer 21224a reaches its maximum efficacy or concentration can occur before time t3. At some later moment in time, the second layer 21224b can be completely, or at least substantially, dissolved by a moment in time indicated by time t5. As the reader will also note, the time t5 can occur after time t2. As the second layer 21224b is being dissolved, the bodily fluid can reach the third layer 21224c and begin to at least partially dissolve the third layer 21224c. Similar to the above, the third layer 21224c can be completely dissolved over the course of minutes, hours, and/or days wherein the material comprising the third layer 21224c can reach a maximum efficacy or concentration at a moment in time indicated as time t6. In various circumstances, a bodily fluid can pass through the outer layer 21224a and the second layer 21224b to reach the third layer 21224c such that the outer layer 21224a, the second layer 21224b, and/or the third layer 21224c can begin to dissolve at the same, or at least substantially the same, time. In any event, the reader will note that the time t3 in which the material comprising the second layer 21224b reaches its maximum efficacy or concentration can occur before time t6. At some later moment in time, the third layer 21224c can be completely, or at least substantially, dissolved by a moment in time indicated by time t8. As the reader will also note, the time t8 can occur after time t5.

[0387] As the third layer 21224c is being dissolved, the bodily fluid can reach the fourth layer 21224d and begin to at least partially dissolve the fourth layer 21224d at a moment in time indicated by time t4. Similar to the above, the fourth layer 21224b can be completely dissolved over the course of minutes, hours, and/or days wherein the material comprising the fourth layer 21224d can reach a maximum efficacy or concentration at a moment in time indicated as time t7. In various circumstances, a bodily fluid can pass through the outer layer 21224a, the second layer 21224b, and the third layer 21224c to reach the fourth layer 21224d such that the outer layer 21224a, the second layer 21224b, the third layer 21224c, and/or the fourth layer 21224d can begin to dissolve at the same, or at least substantially the same, time. In any event, the reader will note that the time t6 in which the material comprising the third layer 21224c reaches its maximum efficacy or concentration can occur before time t7. At some later moment in time, the fourth layer 21224d can be completely, or at least substantially, dissolved by a moment in time indicated by time t9. As the reader will also note, the time t9 can occur after time t8. In various embodiments, as a result of the above, a staged release of medicaments can occur.

[0388] In various embodiments, referring now to FIGS. 81 and 83, a staple cartridge 21300 can comprise a cartridge body 21310 including a plurality of staple cavities 21312 and a plurality of staples 21330 positioned therein. The staple cartridge 21300 can further comprise a tissue thickness compensator 21320 which can include a compensator body 21322 positionable against the cartridge body 21310 and, in addition, a plurality of discrete capsules 21324 positioned within the compensator body 21322. In at least one embodiment, the capsules 21324 can be vertically oriented and, when the staples 21330 are in their unfired configuration, as illustrated in FIG. 83, each capsule 21324 can be positioned between the staple legs 21322 of a staple 21330. In at least one such embodiment, the staple legs 21322 may at least partially extend into the tissue thickness compensator 21320 when the staples 21330 are in their unfired position without rupturing the capsules 21324. When the staples 21330 are moved from their unfired position to their fired position, referring now to FIG. 84, the staples 21330 can rupture the capsules 21324 and thereby release the at least one medicament stored therein. More particularly, in at least one embodiment, the staples 21330 can be deformed by the forming pockets 21062 defined in the anvil 21060 when the staples 21330 are lifted upwardly such that the staple legs 21332 can be curled, or deformed, downwardly and inwardly toward the capsules 21324 positioned therebetween. In at least one embodiment, the staples 21330 can be lifted upwardly by a firing system comprising drivers 21340 and sled 21345 wherein the sled 21345 can be configured to longitudinally traverse the staple cartridge 21000 and sequentially lift and fire the staple drivers 21340 and the staples 21330 positioned thereon. In any event, the staple legs 21332 can pierce and/or crush the capsules 21324 such that the internal cavities 21326 defined in the capsules 21324 can be breached and the one or more medicaments contained in the internal cavities 21326 can escape therefrom. In various embodiments, the one or more medicaments can include one or more powders and/or fluids contained therein, for example. In various embodiments, the staple cartridge 21300 can further comprise a cutting member 21380 which can be advanced distally with the sled 21345 in order to transect the tissue T positioned between the staple cartridge 21300 and the anvil 21060, for example. In at least one embodiment, the cutting member 21380 can be configured to pass through a knife slot 21314 defined in the cartridge body 21310 wherein, in at least one such embodiment, one or more capsules, such as capsules 21324, for example, can be positioned within and/or above the knife slot 21314 such that the cutting member 21380 can transect such capsules 21324. In any event, in various embodiments, the tissue thickness compensator 21320 can further comprise a layer 21321 positioned on the top, and/or bottom, of the cartridge body 21322 which, in at least one embodiment, can be comprised of hyaluronic acid, for example, and can stabilize the cartridge body 21322 and/or the staples 21330. In at least one such embodiment, the cutting member 21380 can be configured to transect the layer 21321 when the cutting member 21380 is advanced through the staple cartridge 21300 as described above.

[0389] In various embodiments, referring now to FIG. 85, a tissue thickness compensator 21420 can comprise a compensator body 21422 and a plurality of capsules 21444 positioned therein. In at least one embodiment, similar to the above, each capsule 21444 can comprise a sealed cavity 21446 which can be configured to releasably store one or medicaments therein. In certain embodiments, each of the capsules 21444 can comprise a conical and/or tapered end 21447, for example. In at least one such embodiment, the tapered ends 21447 can be utilized to hold the capsules 21444 in position while the cartridge body 21422 is being formed around it. In various embodiments, a mold can include a plurality of apertures and/or indentations which can be configured to receive and secure the tapered ends 21447 such that, when the compensator material is poured around the capsules 21444, the mold can hold the capsules 21444 in position. In certain embodiments, further to the above, the capsules 21444 can be positioned and arranged such that they may not be ruptured or burst until staples are fired into and/or through the tissue thickness compensator 21420 during use, for example.

[0390] In certain other embodiments, referring now to FIG. 86, a tissue thickness compensator 21520 can comprise a plurality of capsules 21524 positioned within a compensator body 21522. In at least one embodiment, the capsules 21524 can each comprise one or more apertures 21528 defined in the outer wall thereof wherein the apertures 21528 can be configured to permit one or medicaments 21525 to escape from the cavities 21526 defined in the capsules 21524. In various embodiments, the apertures 21528 can be sized and configured to control the rate in which the medicaments 21525 escape from the cavities 21526. For instance, larger apertures 21528 can permit a faster release of the medicaments 21525 while smaller apertures 21528 can permit a slower release of the medicaments 21525, for example. In at least one embodiment, the outer wall of each capsule 21524 can be comprised of a tube having ends 21527 which are closed and/or sealed. In various embodiments, the outer walls of the capsules 21524 can be comprised of one or more bioabsorbable polymers, for example, and, in at least one embodiment, the ends 21527 can be closed and/or sealed utilizing a heat-staking process, a thermal-welding process, and/or a laser welding process, for example. In certain embodiments, the outer walls, or shells, of the capsules 21524 can be manufactured utilizing an injection molding process wherein, after the shells have been formed, one or medicaments can be positioned into the shells through one or more open ends thereof. Thereafter, in at least one embodiment, the open end, or ends, in the shell can be capped utilizing a polymer solution, for example. In embodiments in which the walls of the capsules 21524 are comprised of a bioabsorbable material, the apertures 21528 defined therein can grow over time. In at least one such embodiment, the rate in which the medicaments 21525 are released from the cavities 21526 can increase over time.

[0391] In various embodiments, the compensator body 21522 can be comprised of gelatin, for example, and can be manufactured into a foam material utilizing a lypholization process, for example. In at least one embodiment, the capsules 21524 can be inserted into the compensator body 21522 wherein, in at least one such embodiment, the compensator body 21522 can be formed with apertures configured to receive the capsules 21524. In at least one such embodiment, a layer, or film, could then be placed over the compensator body 21522 to cap or enclose the capsules 21524 therein. In certain other embodiments, the capsules 21524 can be positioned within a mold and a compensator material can be formed at least partially around the capsules 21524 to form the compensator body 21522. In any event, the compensator body 21552 can comprise one or more keying, or indexing, features which can be configured to align and orient the tissue thickness compensator 21520 with a cartridge body of staple cartridge such that the capsules 21524 are positioned in a desired position.

[0392] In various embodiments, referring now to FIG. 87, a surgical stapling system can include a staple cartridge 21600 and an anvil 21060, wherein the staple cartridge 21600 and the anvil 21060 can be positioned on opposite sides of tissue T. Similar to other staple cartridges disclosed herein, the staple cartridge 21600 can comprise a cartridge body 21310 including a plurality of staple cavities 21312 and a plurality of staples 21330 positioned therein. In use, referring to FIG. 91, the staples 21330 can be lifted upwardly by drivers 21340 from an unfired position to a fired position such that they are deformed against the anvil 21060 or, more particularly, deformed within the forming pockets 21062. As the staples 21330 are being fired, the staples 21330 can pierce the tissue T and a tissue thickness compensator 21620 attached to the anvil 21060 before the staples 21330 are deformed between their unfired configuration (FIG. 88) and their fired configuration (FIG. 89). In various embodiments, the staples 21330 can be comprised of any suitable material such as stainless steel and/or titanium, for example, and can be configured to apply a compression or clamping force against the tissue thickness compensator 21620 and the tissue T. In at least one embodiment, as illustrated in FIG. 87, the staples 21330 can be arranged in a plurality of rows wherein one staple 21330 can be positioned in each staple cavity 21312. In various embodiments, the staple cartridge 21300 can further comprise piercing members 21635 (FIG. 90) which can be configured to engage and pierce the tissue T, the tissue thickness compensator 21620, and/or one or medicament capsules positioned within the tissue thickness compensator 21620, for example. In at least one such embodiment, the piercing members 21635 can be positioned within the staple cavities 21312 wherein the piercing members 21635 can be fired, or ejected, from the staple cavities 21312 by the drivers 21340. In certain embodiments, further to the above, some staple cavities 21312 of the staple cartridge 21600 can include staples 21330 positioned therein while other staple cavities 21312 can include piercing members 21635 positioned therein. In various embodiments, the staple cartridge 21600 can include some rows of staple cavities 21312 having only staples 21330 positioned therein, some rows having only piercing members 21635 positioned therein, and/or some rows having both staples 21330 and piercing members 21635 positioned therein. In at least the illustrated embodiment, referring to FIG. 91, the inner four rows of staple cavities 21312 may only comprise staples 21330 therein while the outer rows of staple cavities 21312 may comprise both staples 21330 and piercing members 21635 therein. In various embodiments, the staples 21330 and the piercing members 21635 within the outer rows of staple cavities 21312 may be arranged in an alternating arrangement, for example. Referring now to FIG. 92, in at least one embodiment, the staples 21330 and the piercing members 21635 may be arranged in a pattern which comprises two staples 21330, followed by a piercing member 21635, followed by two more staples 21330, followed by a piercing member 21635, and so forth, for example.

[0393] In various embodiments, referring primarily to FIG. 90, each piercing member 21635 can comprise a base 21638 and legs 21637 extending upwardly from opposite sides of the base 21638. Referring now to FIG. 91, the drivers 21340 can each comprise a trough 21348 which can be configured to receive and support the base 21638 of a piercing member 21635. When the drivers 21340 are pushed upwardly by the sled 21345, referring now to FIG. 92, the sled 21345 can sequentially fire the staples 21330 and the piercing members 21635. In various embodiments, referring now to FIG. 91, the staples 21330 may be deformed against the anvil 21060 while the piercing members 21635 may not touch the anvil 21060. In at least one embodiment, referring primarily to FIG. 90, one or both of the legs 21636 of each piercing member 21635 can include a sharp tip 21639 which can be configured to pierce the tissue T and/or the tissue thickness compensator 21620 and at least one barb 21637 which can be configured to retain the legs 21636 in the tissue T and/or the tissue thickness compensator 21620, for example. In some embodiments, a tissue thickness compensator may not be used at all. In certain embodiments, the legs 21636 of the piercing members 21635 may not be long enough to pass all the way through the tissue T, let alone touch the anvil 21060. In certain other embodiments, the legs 21636 may be long enough such that they can contact the anvil 21060 and can be deformed into a different configuration.

[0394] In various embodiments, the piercing members 21635 can be comprised of a material that is different than the material comprising the staples 21330. In at least one embodiment, the piercing members 21635 can be comprised of at least one bioabsorbable polymer, such as PGA, for example. In certain embodiments, the piercing members 21635 can each comprise at least one medicament, such as an anti-bacterial agent, an anti-inflammatory agent, pain medication, and/or a MMP inhibitor, for example. As the piercing members 21635 can be located within the staple lines, for example, the piercing members 21635 can supply one or more medicaments to the tissue T within and/or adjacent to the staple line as the piercing members 21635 are being dissolved and/or bioabsorbed. In various embodiments, the piercing members 21635 can be coated with one or more medicaments. In some embodiments, the piercing members 21635 can comprise one or more medicaments embedded within a structural substrate comprising the piercing members 21635. In at least one embodiment, some piercing members 21635 can be comprised of a first structural substrate and/or a first medicament while other piercing members 21635 can be comprised of a second, or different, structural substrate and/or a second, or different, medicament, for example. In various embodiments, the piercing members 21635 can be manufactured utilizing an injection molding process, for example.

[0395] In various embodiments, referring now to FIGS. 93 and 94, a staple cartridge 21700 can include a cartridge body 21710 and a tissue thickness compensator 21720 positioned on or adjacent to a deck surface 21711 of the cartridge body 21710. In at least one embodiment, similar to the above, the cartridge body 21710 can comprise a plurality of staples cavities 21312 and a plurality of staples positioned therein. The cartridge body 21710 can also include a slot 21714 which can be configured to receive a cutting member, such as cutting member 21380 (FIG. 95), for example, therein. In use, as illustrated in FIG. 95, the cutting member 21380 can be configured to transect the tissue T positioned between the anvil 21060 and the staple cartridge 21700. In various embodiments, referring again to FIGS. 93 and 94, the tissue thickness compensator 21720 can comprise a compensator body 21722 and a plurality of medicament packets, or capsules, 21724 positioned within the compensator body 21722. In at least one embodiment, the capsules 21724 can be positioned and arranged in the compensator body 21722 such that the capsules 21724 overlie the slot 21714 defined in the cartridge body 21710. In use, referring primarily to FIG. 96, the cutting member 21380 can be configured to incise the capsules 21724 as the cutting member 21380 is advanced through the staple cartridge 21700. In at least one such embodiment, the capsules 21724 can be sealed prior to being incised by the cutting member 21380 and, after the capsules 21724 have been incised, the one or more medicaments contained therein can be released. Owing to the position of the capsules 21724 over the slot 21714, in various embodiments, the one or more medicaments can be released onto the portion of the tissue T which has been transected by the cutting member 21380. In at least one embodiment, the one or more medicaments contained within the capsules 21724 can comprise a biologic agent in the form of a powder, for example. In various embodiments, the one or more medicaments in the capsules 21724 can comprise oxidized regenerated cellulose, alginate, and/or calcium, for example.

[0396] In various embodiments, referring again to FIGS. 93 and 94, the capsules 21724 can comprise the same medicaments therein. In various other embodiments, one or more of the capsules 21724 can comprise one or more different medicaments therein. In at least one embodiment, a first plurality of capsules 21724 can comprise a first medicament therein and a second plurality of capsules 21724 can comprise a second medicament therein. In at least one such embodiment, the capsules 21724 can be arranged in an alternating arrangement along the longitudinal path of the cutting member 21380, for example, such that a capsule 21724 including the first medicament can be followed by a capsule 21724 including the second medicament which can be followed by a capsule 21724 including the first medicament, and so forth, for example. In various embodiments, the cutting member 21380 can be configured to mix the first medicament and the second medicament together as the cutting member 21380 is advanced through the staple cartridge 21300. In certain embodiments, referring again to FIGS. 93 and 94, the tissue thickness compensator 21720 can further comprise one or more channels 21726 extending outwardly from each capsule 21724. In various embodiments, the channels 21726 can be configured to allow the medicaments within the capsules 21724 to migrate within the tissue thickness compensator 21720, and the tissue T positioned thereagainst, after the capsules 21724 have been severed. In various embodiments, the capsules 21724 can be configured such that they do not burst when a compressive load is applied thereto by the anvil 21060. In at least one embodiment, referring primarily to FIGS. 93 and 96, the cartridge body 21710 can comprise a plurality of recesses 21715 which can each be configured to receive at least a portion of a capsule 21724 therein. In at least one such embodiment, the recesses 21715 can be configured to permit the capsules 21724 to slide downwardly within the recesses 21715 when a compressive load is applied thereto such that the capsules 21724 may not burst. In various other embodiments, one or more of the capsules 21724 could be configured to burst only when a certain compressive force applied thereto is met or exceeded. In at least one such embodiment, the capsules 21724 can be configured to withstand the clamping pressure applied by the anvil 21060 but may burst when the compressive pressure applied thereto increases as a result of the cutting member 21380 being advanced through the staple cartridge 21700, for example. In at least one embodiment, the capsules 21724 can include a lubricant therein which can facilitate the movement of the cutting member 21380 as it is advanced and/or retracted within the staple cartridge 21700.

[0397] In various embodiments, referring now to FIG. 97, a tissue thickness compensator 21820 can comprise a compensator body 21822 and a longitudinal tube 21824 extending therethrough. In at least one embodiment, similar to the above, the tube 21824 can comprise a longitudinal cavity 21826 defined therein and one or more medicaments 21825 positioned within the cavity 21826. In various embodiments, the longitudinal tube 21824 can further include one or more support legs 21827 extending outwardly therefrom which can be configured to support the tube 21824. In at least one such embodiment, referring now to FIG. 98, the support legs 21827 can support the tube 21824 within a mold 21890 while the compensator body 21822 is formed around the tube 21824. In various embodiments, referring now to FIGS. 99 and 100, the material comprising the compensator body 21822, such as PGA and/or PCL, for example, can be poured around the tube 21824 and then lyophilized, foamed, and/or solidified, for example. In at least one embodiment, referring again to FIG. 98, the material comprising the compensator body 21822 can be poured into a cavity 21891 surrounding the tube 21824 wherein the cavity 21891 can then be closed by a cover 21892. In various embodiments, referring to FIG. 97, the ends of the support legs 21827 may not be covered by the poured material and may be flush with the bottom surface 21821 of the compensator body 21822. In at least one embodiment, the support legs 21827 and/or the tube 21824 can be comprised of a dissolvable and/or bioabsorbable material, such as gelatin, hyaluronic acid, PDS, and/or ORC, for example. In certain embodiments, the legs 21827 can be rapidly dissolved by bodily fluids and/or a saline solution, for example, wherein channels or passages can be left behind that extend between the outer perimeter and the interior of the tissue thickness compensator 21820. In at least one embodiment, such passages can be created to permit the one or more medicaments 21825 positioned within the tube 21824 to be rapidly dissolved and/or absorbed. An alternative embodiment of a tissue thickness compensator, such as tissue thickness compensator 21920, for example, can comprise a compensator body 21922 and a tube 21924 including a plurality of support legs 21927, as illustrated in FIG. 101. In at least one embodiment, referring to FIG. 102, the support legs 21927 can be part of a larger support network or structural lattice 21928 that can extend through the compensator body 21922.

[0398] In various embodiments, referring again to FIG. 97, the legs 21827 extending from the tube 21824 can also include one or more medicaments therein. When the legs 21827 are dissolved and/or absorbed, as described above, the one or more medicaments in the legs 21827 can provide a first medicated response to stapled and/or incised tissue while the one or more medicaments 21825 in the tube 21824 can provide a second, or subsequent, medicated response, in at least one embodiment. In certain embodiments, referring now to FIGS. 103 and 105, a tissue thickness compensator 22020 can comprise a compensator body 22022 and a longitudinal medicament tube 22024 extending through the compensator body 22022. Similar to the above, the tube 22024 can define a longitudinal cavity 22026a including one or more medicaments 22025a positioned therein. Also similar to the above, the tube 22024 can include a plurality of longitudinal leg supports 22027 that can extend along the length of the tube 22024. In various embodiments, each of the leg supports 22027 can define a longitudinal cavity, such as cavities 22026b and 22026c, for example, therein which can each include one or more medicaments, such as medicaments 22025b and 22025c, for example, therein. In various embodiments, the leg supports 22027 can be comprised of a material which can be quickly dissolved and/or absorbed such that the medicaments 22025b and 22025c can be quickly released. Thereafter, in at least one embodiment, the support legs 22027 and the tube 22024 can be further dissolved and/or absorbed such that the medicament 22025a can be subsequently released. In various embodiments, the medicaments 22025a, 22025b, and/or 22025c can be comprised of the same material. In other embodiments, the medicaments 22025a, 22025b, and/or 22025c can be comprised of different materials. In at least one embodiment, the medicaments 22025b and 22025c can be comprised of the same material, or materials, which can be different than the material, or materials, comprising medicament 22025a.

[0399] In various embodiments, further to the above, the tube 22024, the legs 22027, and/or the cavities 22026a-22026c defined therein can be manufactured utilizing an injection molding process. In certain embodiments, the tube 22024, the legs 22027, and/or the cavities 22026a-22026c can be manufactured utilizing an extrusion process, for example, wherein, as a result, such features can comprise a continuous cross-section along the length thereof. As a result of such processes, in various embodiments, the tubes 22024 and the legs 22027 can be integrally formed. Thereafter, in at least one embodiment, the medicaments 22025a-22025c can be positioned within the cavities 22026a-22026c, respectively. In various embodiments, the medicaments 22025a-22025c can each be comprised of one or more powders and/or one or more fluids, for example. In certain embodiments, referring now to FIG. 106, the ends 22029 of the cavities 22026a-22026c can be sealed in order to contain the medicaments 22025a-22025c therein. In any event, the tube 22024 can then be positioned within a mold, such as the mold 21890 described above, for example, wherein the material comprising the compensator body 22022 can be poured around the tube 22024, as illustrated in FIG. 104, to form the tissue thickness compensator 22020. Various alternative embodiments are illustrated in FIGS. 107 and 108. Referring to FIG. 107, a tissue thickness compensator 22120 can comprise a compensator body 22122 and a plurality of longitudinal tubes 22124 which are connected together. In at least one embodiment, each of the tubes 22124 can define a longitudinal cavity 22126 therein which can each include one or more medicaments 22125 therein. In various embodiments, the longitudinal cavities 22126 may not be in fluid communication with each other while, in some embodiments, one or more of the longitudinal cavities 22126 can be in fluid communication with each other. Similar to the above, the compensator 22120 can further comprise legs 22127 that extend downwardly from the tubes 22124 and can each include a longitudinal cavity 22126 and at least one medicament 22125 therein. In various embodiments, the tubes 22124 and/or the support legs 22127 can be comprised of materials which can be configured to dissolve and/or biabsorb at different rates. In at least one such embodiment, the support legs 22127 can be comprised of a material which can be dissolved and/or bioabsorbed at a faster rate than the material comprising the tubes 22124, for example. Referring now to FIG. 108, a tissue thickness compensator 22220 can comprise a compensator body 22222 and a longitudinal tube 22224 wherein the tube 22224 can include a plurality of support legs 22227 extending therefrom. In at least one embodiment, a single longitudinal cavity 22226 can be defined within the tube 22224 and can extend into the support legs 22227. Similar to the above, the cavity 22226 can include one or more medicaments 22225 positioned therein.

[0400] In various embodiments, referring again to FIG. 97, the support legs 21827 can be comprised of one or materials which can be configured to adsorb a fluid, such as blood and/or a saline solution, for example. In at least one embodiment, the support legs 21827 can be configured to wick the fluid toward the tube 21824 and the one or more medicaments 21825 contained therein. In certain embodiments, such wicking can allow the medicaments 21825 to dissolve and/or bioabsorb earlier in the healing process. In at least one embodiment, the ends of the support legs 21827 may not be covered by the compensator body 21822 and may be exposed to the fluid. In various embodiments, this wicking process can occur by capillary action and can occur regardless of the orientation of the tissue thickness compensator 21820, for example.

[0401] In various embodiments, referring now to FIG. 112, a tissue thickness compensator 22320 can comprise a compensator body 22322 and a plurality of tubes 22324 positioned therein. In certain embodiments, the compensator body 23222 can be comprised of a regenerative tissue scaffold foam, such as an acellular omentum biomatrix, Omentum Scaffold Material, and/or ACell, for example. In at least one embodiment, the Omentum Scaffold Material can comprise a hydrophilic foam produced from skeletonized omentum and, in certain embodiments, can be compressible. When exposed to a fluid, the Omentum Scaffold Material can expand and apply pressure to the tissue positioned thereagainst. In at least one embodiment, ACell is a regenerative product that provides an extracellular matrix or scaffolding network to encourage cellular proliferation and migration. In at least one embodiment, the tissue scaffold comprising the compensator body 22322 can be loaded with stem cells, PRP, or growth factors, for example. In at least one embodiment, the tissue scaffold comprising the compensator body 22322 can be coated in a collagen matrix, for example. In various embodiments, the tissue scaffold matrix of the compensator body 22322 can be comprised of a fiber matrix and, in at least one embodiment, the fiber matrix can be comprised of randomly-oriented fibers. In some circumstances, a fiber matrix comprised of randomly-oriented fibers may not be able to provide a desired elasticity or resiliency within the compensator body 22322. To account for this, in various embodiments, the randomly-oriented fibers can be comprised of a hydrophilic material and/or can be coated with a hydrophilic material which, after being exposed to a liquid, can be configured to expand and provide a desired resiliency to the fiber matrix and/or a desired compression force to the tissue. In various circumstances, the fiber matrix may not be exposed to a liquid until after it has been captured against tissue by a plurality of staples, as described above. In at least one such embodiment, the compensator body 22322 can comprise a liquid-impermeable wrap which can be broken, punctured, incised, and/or torn, for example, in use to allow the liquid to enter into the compensator body 22322 and access the hydrophilic fibers. In any event, when the liquid is absorbed by the scaffold matrix captured within the staples, the scaffold matrix can expand to apply a compressive pressure to the tissue also captured within the staples and, over time, accommodate tissue ingrowth into the scaffold matrix.

[0402] In various embodiments, further to the above, the tubes 22324 of the tissue thickness compensator 22320 can be comprised of a degradable material which can be configured to dissolve and/or bioabsorb. Similar to the above, each tube 22324 can include a sealed inner cavity having one or medicaments contained therein and, in addition, one or more support legs 22327 which can be configured to degrade and provide a channel or flow path for liquids to reach the medicament stored within the tube 22324. Such degradation of the support legs 22327 may take time and, as a result, the medicament contained within the tubes 22324 may not be immediately released. In a sense, a period of time may be required for a fluid to degrade the legs 22327 wherein, as a result, the legs 22327 can serve as a fuse designed to delay the release of the medicament within the tubes 22324. Thus, in various circumstances, legs 22327 having longer lengths and/or thicker cross-sections may provide a longer delay while legs 22327 having shorter lengths and/or thinner cross-sections may provide a shorter delay. In certain embodiments, the tubes 22324 can be comprised of a material which dissolves quickly and/or slowly; however, in either event, the degradation of the tubes 22324 can occur over a period of time which can delay the release of the one or more medicaments contained within the tubes 22324. In various embodiments, a first tube 22324 can be comprised of a first material which degrades at a first rate and a second tube 22324 can be comprised of a second material which degrades at a second, or different, rate. In such embodiments, a first medicament contained within the first tube 22324 can be released before a second medicament contained within the second tube 22324, for example. In certain embodiments, a first tube 22324 can have a thinner outer wall than a second tube 22324 which can allow the first tube 22324 to degrade faster than the second tube 22324 and allow a medicament contained within the first tube 22334 to be released before a medicament in the second tube 22324, for example. As a result of the above, in various embodiments, a first tube 22324 can be configured to release a first medicament at a first point in time, a second tube 22324 can be configured to release a second medicament at a second, or later, point in time, and a third tube 22324 can be configured to release a third medicament at a third, or even later, point in time, for example.

[0403] In various embodiments, referring now to FIGS. 113 and 114, a tissue thickness compensator 22420 can comprise a compensator body 22422 and a sealed vessel 22424 positioned within the compensator body 22422. In at least one embodiment, similar to the above, the vessel 22424 can define a longitudinal cavity 22426 and one or more medicaments 22425 positioned within the longitudinal cavity 22426. In certain embodiments, the vessel 22424 can be resilient such that, when the tissue thickness compensator 22420 is compressed, or flattened, as illustrated in FIG. 114, the vessel 22424 can seek to spring back or retain its original, undeformed shape. In at least one such embodiment, the vessel 22424 can comprise an elastic spring member positioned within the compensator body 22422. In at least one embodiment, the vessel 22424 can be configured to change shape without rupturing. In at least one such embodiment, the vessel 22424 can degrade when exposed to a liquid, for example, as described herein.

[0404] In various embodiments, referring now to FIG. 115, a tissue thickness compensator 22520 can comprise a compensator body 22522 and a plurality of sealed vessels 22524a-22524c. In at least one embodiment, each of the vessels 22524a-22524c can define an outer perimeter which is configured to increase, maximize, and/or optimize the surface area of the vessel that comes into contact with a liquid, such as blood and/or a saline solution, for example. In various circumstances, vessels having a larger surface area may be exposed to a larger quantity of liquid and, as a result, can be dissolved and/or bioabsorbed at a faster rate. Correspondingly, vessels having a smaller surface area may be exposed to a smaller quantity of liquid and, as a result, can be dissolved and/or bioabsorbed at a slower rate. In various embodiments, the vessels 22524a-22524c can be comprised of gelatin, hyaluronic acid, PDS, and/or ORC, for example. Similar to the above, in certain embodiments, the vessels 22524a-22524c can be resilient and can provide a spring-back or elastic biasing force. In various embodiments, referring now to FIG. 116, a tissue thickness compensator 22620 can comprise a compensator body 22622 and a plurality of resilient laminate members 22624 positioned within the compensator body 22622. In at least one embodiment, each of the laminate members 22624 can comprise a sealed inner channel including one or more medicaments positioned therein.

[0405] In various embodiments, referring now to FIG. 117, an end effector of a surgical stapling instrument can comprise an anvil 21060 and a staple cartridge 22700. In at least one embodiment, the anvil 21060 can comprise a tissue thickness compensator 22770 attached thereto and the staple cartridge 22700 can comprise a cartridge body 22710 and a tissue thickness compensator 22720. In certain embodiments, referring now to FIG. 118, the tissue thickness compensator 22770 can comprise a plurality of layers wherein, in at least one embodiment, the tissue thickness compensator 22720 can comprise a first layer 22771 and a second layer 22772, although other embodiments are envisioned in which a tissue thickness compensator can comprise more than two layers. In various embodiments, one or more of the layers of the tissue thickness compensator can comprise a woven material. In at least one embodiment, the first layer 22771 can be comprised of a plurality of first threads 22773 comprised of a first material and a plurality of second threads 22774 comprised of a second, or different, material. Similarly, the second layer 22772 can be comprised of a plurality of first threads 22773 and a plurality of second threads 22774. In certain embodiments, the concentrations of the first threads 22773 and the second threads 22774 in the first layer 22771 can be the same as the concentrations of the first threads 22773 and the second threads 22774 in the second layer 22772. In certain other embodiments, the concentrations of the first threads 22773 and the second threads 22774 in the first layer 22771 can be different than the concentrations of the first threads 22773 and the second threads 22774 in the second layer 22772, as discussed in greater detail below.

[0406] In various embodiments, further to the above, the first threads 22773 can be comprised of bioabsorbable polymer, such as PGA, PDS, PCL, and/or PLA, for example, and the second threads 22774 can be comprised of oxidized regenerated cellulose (ORC), for example. In certain embodiments, the first layer 22771 can comprise an outer layer of the tissue thickness compensator 22770 and can include a tissue contacting surface. In at least one embodiment, the first layer 22771 can comprise more first threads 22773 than second threads 22774. In at least one such embodiment, the first layer 22771 can comprise a ratio of approximately 80% first threads 22773 to approximately 20% second threads 22774, for example. In various embodiments, the first layer 22771 can comprise a ratio of approximately 60% first threads 22773 to approximately 40% second threads 22774, a ratio of approximately 67% first threads 22773 to approximately 33% second threads 22774, a ratio of approximately 70% first threads 22773 to approximately 30% second threads 22774, a ratio of approximately 75% first threads 22773 to approximately 25% second threads 22774, and/or a ratio of approximately 90% first threads 22773 to approximately 10% second threads 22774, for example.

[0407] In various embodiments, further to the above, the first threads 22773 can be comprised of a material which dissolves, bioabsorbs, and/or changes state at a slower rate than the material comprising the second threads 22774. In at least one such embodiment, the second threads 22774 can be comprised of ORC threads which can change from a solid to a gel when they are exposed to a liquid, for example, and, in at least one embodiment, the ORC threads can react and change from a solid to a gel when they are exposed to platelets, for example. In such embodiments, however, the first layer 22773 can be mostly comprised of bioabsorbable polymer threads which can react to liquids much slower than the ORC threads and, thus, in at least one embodiment, the first layer 22773 can come into contact with tissue or bodily fluids on multiple occasions without losing its overall shape and structure. That said, the ORC fibers in the first layer 22773 can react when they first come into contact with a liquid and/or tissue; however, the ORC gel can be at least partially or mostly retained within the first layer 22773.

[0408] In various embodiments, the second layer 22772 can comprise an inner layer of the tissue thickness compensator 22770 and may not include a direct tissue contacting surface. In at least one embodiment, the second layer 22772 can comprise less first threads 22773 than second threads 22774. In at least one such embodiment, the second layer 22772 can comprise a ratio of approximately 20% first threads 22773 to approximately 80% second threads 22774, for example. In various embodiments, the second layer 22772 can comprise a ratio of approximately 40% first threads 22773 to approximately 60% second threads 22774, a ratio of approximately 33% first threads 22773 to approximately 67% second threads 22774, a ratio of approximately 30% first threads 22773 to approximately 70% second threads 22774, a ratio of approximately 25% first threads 22773 to approximately 75% second threads 22774, and/or a ratio of approximately 10% first threads 22773 to approximately 90% second threads 22774, for example.

[0409] In various embodiments, further to the above, the second layer 22772 can comprise more ORC threads than bioabsorbable polymer threads, for example. In certain embodiments, the second layer 22772 can comprise more ORC threads than the first layer 22771. As the second layer 22772 is not an outer layer, in various embodiments, liquids may not immediately contact the second layer 22772 as they would have to first pass through the first layer 22771 before contacting the second layer 22772. In such embodiments, the second layer 22772 can comprise a higher density of ORC threads as the ORC threads in the second, protected, layer 22772 would not immediately turn into a gel. Even if the ORC threads in the second layer 22772 were to come into contact with a liquid and turn into a gel, the ORC gel could be contained in the tissue thickness compensator 22770 by the first layer 22771 which, as described above, can maintain its general shape, at least initially, and provide a support mesh to the second layer 22772. While ORC fibers and bioabsorbale fibers can be utilized in various embodiments, other suitable materials could be utilized.

[0410] Further to the above, referring now to FIGS. 121-123, the tissue thickness compensator 22770 can be positioned intermediate an anvil 21060 and tissue T, wherein the tissue thickness compensator 22770 can be compressed against the tissue T before staples 21330 are fired from the staple cartridge 22700. After the staples 21330 have been fired to capture the tissue T and the tissue thickness compensators 22720 and 22770 therein, the anvil 21060 and the cartridge body 22710 of the staple cartridge 22700 can be moved away from the compensators 22720, 22770 and the tissue T and removed from the surgical site. In various embodiments, referring now to FIG. 119, a layer 22871 of a tissue thickness compensator can comprise woven threads 22873 which can include an elongate, or flattened, cross-section, for example. In certain embodiments, referring now to FIG. 120, a layer 22971 of a tissue thickness compensator can comprise woven threads 22973 which can include a round cross-section, for example.

[0411] Various alternative embodiments are illustrated in FIGS. 124-127. Referring now to FIG. 125, an end effector of a surgical stapling instrument can include an anvil 21060 and a tissue thickness compensator 22770′ positioned thereon. In various embodiments, referring to FIG. 124, the tissue thickness compensator 22270′ can comprise a layer 22771′ which can include a plurality of first fibers 22773′ woven with a plurality of second fibers 22774′. In at least one such embodiment, the first fibers 22773′ can be configured to dissolve and/or bioabsorb at a faster rate than the second fibers 22774′. In certain embodiments, gaps, openings, and/or pockets can be defined between the first fibers 22773′ and the second fibers 22773″ which can permit liquids to flow through the layer 22771′. Referring now to FIG. 127, an end effector of a surgical stapling instrument can include a tissue thickness compensator 22770″ attached to an anvil 21060. In various embodiments, referring to FIG. 126, the tissue thickness compensator 22770″ can comprise a woven layer of threads 22771″ which can be embedded and/or encased within a substrate 22772″. In at least one embodiment, the threads 22771″ can be exposed while, in other embodiments, at least a portion of the substrate 22772″ may have to be dissolved and/or bioabsorbed before the threads 22771″ are exposed. In at least one such embodiment, the material comprising the substrate 22772″ may fill within any gaps, openings, or pockets defined between the threads 22771″.

[0412] In various embodiments, referring now to FIG. 132, a staple cartridge 23000 can include a tissue thickness compensator 23020. As discussed herein, a tissue thickness compensator can be manufactured utilizing a lypholization process, for example. In at least one embodiment, a solution comprising PGA and/or PCL, for example, can be poured into a mold wherein the solution can be permitted to grow into an open cell foam in the presence of a vacuum atmosphere and/or reduced temperature, for example. In at least one such embodiment, the PGA material can be present in the solution according to an approximately 64/36 ratio by weight with respect to the PLA material, for example. In various embodiments, referring to FIG. 128, fibers and/or filaments 23021, for example, can be mixed into the solution. In at least one embodiment, PGA fibers, for example, can be dispersed within the solution before it is poured into the mold such that the PGA fibers can be evenly, or at least substantially evenly, distributed throughout the tissue thickness compensator 23020, for example. In other circumstances, the PGA fibers can be placed in the solution, and/or directly into the mold, for example, such that the PGA fibers can precipitate or settle toward the bottom of the mold, for example. In other circumstances, the PGA fibers could be configured to float to the top of the solution. In any event, in certain embodiments, a solvent, such as dioxane solvent, for example, can be present in the solution which can assist in the lypholization process. In various embodiments, the dioxane solvent may not react, or at least substantially react, with the PGA fibers within the solution.

[0413] In various embodiments, further to the above, the fibers 23021 can be coated with one or more medicaments before they are mixed into and/or with the solution. In certain embodiments, referring to FIG. 130, each fiber 23021 can comprise a substrate 23022 which can be at least partially coated with a coating 23023 utilizing any suitable manufacturing process. Referring to FIG. 129 the fibers 23021 can be manufactured utilizing an extruding process in which at least one drug coating is placed on a PGA substrate, for example. Such embodiments may be particularly useful for drugs that can withstand the elevated temperature of an extruding process. Referring to FIG. 131, the fibers 23021 can be coated and/or impregnated with a drug utilizing a carrier fluid, such as supercritical carbon dioxide, for example. In any event, in various embodiments, the drug-coated fibers 23021 can be mixed with the solution such that the fibers 23021 become embedded within the tissue thickness compensator 23020. In various circumstances, as a result, the coatings of the fibers 23021 may begin to dissolve and elude the one or more medicaments contained therein. In certain embodiments, the fibers 23021 positioned closer to the perimeter of the tissue thickness compensator 23020 may begin to dissolve before the fibers 23021 positioned closer to the interior of the tissue thickness compensator 23020. In such embodiments, the dissolved fibers 23021 may leave behind a plurality, or network, of cavities within the tissue thickness compensator 23020 wherein, in at least one embodiment, such cavities can permit cellular or tissue ingrowth within the tissue thickness compensator 23020. In certain embodiments, a tissue thickness compensator can comprise a plurality of first fibers which can dissolve at a faster than a plurality of second fibers. In at least one such embodiment, the first fibers can comprise PGA fibers, for example, which have been gamma irradiated. In various embodiments, gamma irradiated PGA fibers can dissolve faster than non-gamma irradiated PGA fibers, for example.

[0414] In various embodiments, one or more colorants can be added to the solution described above such that the tissue thickness compensator produced from the solution can have a suitable color. In at least one embodiment, it may be desirable for the tissue thickness compensator to have a color which contrasts with its surrounding environment. In at least one such embodiment, the tissue thickness compensator can be green and/or blue, for example.

[0415] In various embodiments, referring now to FIGS. 133 and 135, a tissue thickness compensator 23120 can comprise a compensator body 23122 and a plurality of medicament particles 23121 distributed throughout the compensator body 23122. In at least one embodiment, the compensator body 23122 can be comprised of a hydrophobic material. In at least one such embodiment, the compensator body 23122 can be comprised of a material including PCL/PGA, for example, wherein the PCL and PGA can be present in the material according to a 65/35 ratio by weight. In certain embodiments, referring now to FIG. 134, the medicament particles 23121 can comprise one or more drugs 23123, such as doxycycline, percarbonate, and/or ascorbic acid phosphate, for example, which can be encapsulated by and/or incorporated within a casing or shell 23124 comprised of a hydrophilic material, for example. In at least one embodiment, the shell 23124 can be comprised of low molecular weight gelatin, hyaluronic acid, and/or CMC, for example. In various embodiments, the medicament 23121 can be manufactured as microparticles which can be distributed within a solution and poured into a mold where the solution can be subsequently lyophilized, for example, as described above. Once the tissue thickness compensator 23120 has been exposed to a liquid, in use, a fluid 23129 (FIG. 136) can enter into the compensator body 23122 and dissolve and/or absorb the hydrophilic shell 23124 of the medicament particles 23121, for example. In various embodiments, referring now to FIG. 139, a tissue thickness compensator 23220 can comprise a first layer 23222 and a second, or outer, layer 23224 which, in at least one embodiment, can comprise a plurality of coated drug particles 23221 dispersed therein. Similar to the above, the particles 23221 can be dissolved and/or absorbed from the second layer 23224 and can leave behind openings or capillary paths 23225, for example, within the second layer 23224, for example. In certain embodiments, referring now to FIG. 140, a tissue thickness compensator 23320 can comprise a compensator body 23322 comprising a plurality of medicament particles 23121 and a plurality of fibers 23021 distributed therein, for example.

[0416] In various embodiments, referring now to FIGS. 141 and 142, a staple cartridge 23400 can include a cartridge body 23410 and a tissue thickness compensator 23420 positioned thereon, for example. In at least one embodiment, the tissue thickness compensator 23420 can comprise a plurality of capsules 23421 positioned within the compensator body 23422. In certain embodiments, the capsules 23421 can be manufactured utilizing an emoulism, or spin disk, process, for example, and, in at least one embodiment, the capsules 23421 can comprise microspheres of solid and/or liquid biometrics, for example. In various embodiments, the capsules 23421 can include one or more adhesives which, when released from the capsules 23421, can help secure tissue sealing. Certain embodiments are envisioned in which the capsules 23421 can include haemostatic agents, for example. In any event, in various embodiments, the capsules 23421 can be distributed within the compensator body 23422 in any suitable manner. In at least one embodiment, referring now to FIG. 143, the capsules 23421 can be placed in a mold cavity 21891 defined in a mold 21890, for example, wherein the capsules 23421 can settle to the bottom 21893 of the mold 21890. In certain embodiments, referring to FIG. 144, the mold 21890 can be vibrated such that the capsules 23421 can form an even, or an at least substantially even, layer on the bottom 21893. In various embodiments, referring now to FIG. 145, the material comprising the compensator body 23422 can be poured into the mold cavity 21891 with the capsules 23421. In certain embodiments, the capsules 23421 can be denser than the compensator body material and, as a result, the capsules 23421 may remain at the bottom 21893 of the mold 21890 as illustrated in FIG. 146. In at least one such embodiment, referring to FIG. 148, the bottom 21893 of the mold 21890 can include a plurality of recesses, depressions, and/or dimples 21899 which can be configured to receive the capsules 23421. In certain other embodiments, referring to FIG. 147, the capsules 23421 can be less dense than the compensator body material and may float to the top of the mold 21890. In various embodiments, as described in greater detail further below, the density of the capsules 23421 can be selected such that the capsules 23421 can float throughout the compensator body material.

[0417] After the mixture comprising the capsules 23421 and the compensator body material has been suitably poured into the mold 21890, the mixture can undergo a lypholization process, for example, to form the tissue thickness compensator 23420. In at least one such embodiment, the capsules 23421 can be secured or freeze-dried into position within the compensator body 23422. Thereafter, referring again to FIG. 141, the tissue thickness compensator 23420 can be removed from the mold 21890 and then assembled to the cartridge body 23410 of the staple cartridge 23400. As illustrated in FIG. 141, the tissue thickness compensator 23420 can be positioned and arranged such that capsules 23421 can define, or are positioned adjacent to, a tissue-contacting surface, or skin, 23425 of the tissue thickness compensator 23420. In certain embodiments, the capsules 23421 can be at least partially comprised of a hydrophilic material, for example, which can be quickly dissolved and/or bioabsorbed after the tissue thickness compensator 23420 has been positioned against tissue, for example. In at least one embodiment, each of the capsules 23421 can be comprised of multiple layers of materials which can be dissolved and/or bioabsorbed over time. In at least one such embodiment, an outer layer of a capsule 23421 can comprise a first medicament which can be dissolved and/or bioabsorbed to expose a second, or inner, layer comprising a second medicament which can then be dissolved and/or bioabsorbed, for example. In at least one embodiment, some of the capsules 23421 can be positioned such that they are incised by a cutting member, described elsewhere herein, as the cutting member is progressed distally to incise the tissue and/or the tissue thickness compensator 23420. In at least one embodiment, the capsules 23421 can decrease the density of the tissue thickness compensator 23420 which can reduce the force or energy needed to advance the cutting member through the tissue thickness compensator 23420, for example.

[0418] As discussed above, various embodiments of a tissue thickness compensator 23420 can comprise capsules 23421 positioned on one or more sides, or skins, on the compensator body 23422. As also discussed above, certain embodiments of a tissue thickness compensator 23420 can comprise capsules 23421 dispersed throughout the compensator body 23422. In at least one such embodiment, the capsules 23421 can have the same density of the compensator body material such that the capsules 23421 can float within the compensator body material. In certain embodiments, the capsules 23421 can be dispersed, or homogenized, throughout the compensator body material wherein the mixture can then be cooled before the capsules 23421 settle, or at least substantially settle, to the bottom of the mold.

[0419] In various embodiments, referring now to FIG. 149, a tissue thickness compensator 23520 can comprise a shell 23522 and a plurality of movable elements 23524 positioned within the shell 23522. In at least one embodiment, the shell 23322 can define an enclosed and/or sealed space, such as cavity 23523, for example, within which the movable elements 23524 can move. In certain embodiments, the movable elements 23254 can be spherical in shape, for example, and can be configured to slide and/or roll, for example, relative to each other. In various embodiments, the tissue thickness compensator 23520 can be positioned over a cartridge body 21310 of a staple cartridge wherein staples 21330 can be fired from the staple cartridge and through the tissue thickness compensator 23520, as illustrated in FIG. 150. In various circumstances, the movable elements 23524 can be configured to move to the sides of the staples 21330 being fired through the tissue thickness compensator 23520 such that the elements 23524 may not be ruptured during the firing process. In at least one such embodiment, the shell 23522 can be comprised of a resilient material which can be configured to flex and/or shift in order to accommodate the movement of the movable elements 23524 and dynamically redistribute the forces generated within. In certain embodiments, the shell 23522 can enclose a medium. In at least one such embodiment, the medium can comprise one or more powders, liquids, gasses, fluids, and/or gels, for example, within which the movable elements 23524 can move. In various embodiments, the movable elements 23524 can be comprised of a dissolvable and/or bioabsorbable material, for example, and one or more medicaments contained therein. In at least one such embodiment, such an arrangement can be configured to provide a delayed and/or sustained release of the one or more medicaments. In certain alternative embodiments, although not illustrated, the tissue thickness compensator 23520 can be positioned between the tissue T and an anvil 21060, for example. In any event, in various embodiments, the tissue thickness compensator 23520 can comprise an enclosed “bean bag” arrangement. In certain embodiments, the shell 23522 can be configured such that it does not rupture, or at least substantially rupture, until a cutting member, such as cutting member 21380, for example, is passed therethrough. At such point, in various embodiments, one or more of the movable elements 23524 could escape from the shell 23522.

[0420] In various embodiments, referring now to FIG. 153, a tissue thickness compensator 23620 can comprise a compensator body 23622 and a plurality of capsules 23624 at least partially contained therein. In certain embodiments, referring now to FIG. 151, a mold 23690 can be utilized to manufacture the tissue thickness compensator 23620. In at least one such embodiment, a plurality of spherical capsules 23624 can be positioned within a cavity 23691 defined in the mold 23690 wherein the lateral movement of the capsules 23624 within the mold 23690 can be arrested or stopped by lateral sidewalls 23694 of the mold 23690 and lateral stops 23693 extending between the lateral sidewalls 23694, for example. In various embodiments, the lateral sidewalls 23694 and the lateral stops 23693 can define a plurality of pockets within which the capsules 23624 can be positioned and contained. In certain embodiments, the capsules 23624 can be configured to rest on the bottom surface 23699 of the mold 23690. In other embodiments, referring to FIGS. 151 and 152, the mold 23690 can further comprise one or more longitudinal supports 23692 which can be configured to suspend the capsules 23624 such that they are not in contact with the bottom surface 23699 of the mold 23690. In at least one such embodiment, the longitudinal supports 23692 can be positioned on the bottom surface 23699 while, in other embodiments, referring to FIG. 152, the longitudinal supports 23692 can be positioned on the lateral supports 23693.

[0421] In various embodiments, referring again to FIGS. 151 and 152, a material comprising the compensator body 23622 can be poured into the cavity 23691 of the mold 23690 such that the capsules 23624 are at least substantially surrounded by the material. In at least one embodiment, referring primarily to FIG. 153, portions of the capsules 23624 can protrude from the compensator body 23622 of a tissue thickness compensator 23620. In certain embodiments, the lateral supports 23693 and/or the longitudinal supports 23692 can be withdrawn from the mold 23691 during and/or after the compensator body 23622 has undergone a lypholization process, for example. At such point, the capsules 23624 can be suspended within the compensator body 23622 without structural supports. In various other embodiments, the lateral supports 23693 and/or the longitudinal supports 23692 can remain in the compensator body 23622. In at least one such embodiment, the lateral supports 23693 and/or the longitudinal supports 23692 can be comprised of a bioabsorbable material, for example. In certain embodiments, the supports 23692 and/or the supports 23693 can comprise elastic members positioned within the compensator body 23622 which can increase the resiliency of the compensator body 23622, for example.

[0422] In various embodiments, referring now to FIG. 157, a tissue thickness compensator 23720 can comprise a compensator body having first and second portions, 23722a and 23722b, and at least one capsule 23724 positioned therebetween. In at least one embodiment, the tissue thickness compensator 23720 can be manufactured utilizing mold 21890, for example. Referring now to FIG. 154, a first material can be poured into the mold 21890 to form the first portion 23722a of the compensator body. Thereafter, referring to FIG. 155, the capsule 23724 can be positioned on the first portion 23722a. In some embodiments, the capsule 23724 can be positioned on the first portion 23722a after a period of time and/or after the first material has undergone a lypholization process, for example. Referring now to FIG. 156, a second material can be poured into the mold 21890 to form the second portion 23722b of the compensator body. After a period of time and/or after the second material has undergone a lypholization process, for example, the tissue thickness compensator 23720 can be removed from the mold 21890 and used in connection with a staple cartridge 23700 as illustrated in FIG. 158, for example. In certain embodiments, the second material can be different than the first material while, in other embodiments, the second material can be the same as the first material. In either event, in various embodiments, the first material and/or the second material can be comprised of a bioabsorbable material and the capsule 23724 can be comprised of at least one medicament, for example.

[0423] In various embodiments, referring now to FIG. 162, a staple cartridge 23800 can comprise a tissue thickness compensator 23820 which can include a compensator body 23822 and a longitudinal capsule 23824 positioned therein. In at least one embodiment, referring now to FIGS. 159 and 160, a longitudinal aperture 23821 can be formed in the compensator body 23822 by any suitable process such as by a mechanical drilling process and/or a laser drilling process, for example. Once the longitudinal aperture 23821 has been formed, a longitudinal capsule 23824 can be positioned within the longitudinal aperture 23821, as illustrated in FIG. 161. In various embodiments, referring now to FIG. 166, a staple cartridge 23900 can comprise a tissue thickness compensator 23920 which can include a compensator body 23922 and a plurality of transverse capsules 23924 positioned therein. In at least one embodiment, referring now to FIGS. 163 and 164, transverse apertures 23921 can be formed in the compensator body 23922 by any suitable process such as by a mechanical drilling process and/or a laser drilling process, for example. Once the transverse apertures 23921 have been formed, a plurality of transverse capsules 239824 can be positioned within the transverse apertures 23921, as illustrated in FIG. 165.

[0424] FIGS. 167-171 illustrate an alternative method for manufacturing the tissue thickness compensator 23820 utilizing a vertical mold 24090. Referring primarily to FIG. 167, the mold 24090 can include a cavity 24091 defined by sidewalls 24092 and a bottom end wall 24093. In at least one embodiment, referring to FIG. 168, the end wall 24093 can comprise an aperture 24094 which can be configured to receive an end of the longitudinal capsule 23824 and hold the capsule 23824 in an upright position, as illustrated in FIG. 169. Thereafter, referring now to FIG. 170, the open side of the cavity 24091 can be closed and/or sealed by a cover 24095 such that the material comprising the compensator body 23822 can be poured into the cavity 24091 through an open end of the mold 24090. After the material comprising the compensator body has solidified, cured, and/or lyophilized, for example, the tissue thickness compensator 23820 can be removed from the mold 24090.

[0425] In various embodiments, referring now to FIG. 172, a staple cartridge 24100 can comprise a cartridge body 24110, a tissue thickness compensator mat 24170 positioned against a deck surface 24111 of the cartridge body 24110, and a tissue thickness compensator 24120 positioned on top of the tissue thickness compensator mat 24170. In at least one embodiment, the tissue thickness compensator 24120 and the tissue thickness compensator mat 24170, together or independently, can compensate for variations in the thickness of the tissue captured within staples, such as staples 21330 (FIG. 175), for example, fired from the staple cartridge 24100. In various embodiments, referring primarily to FIGS. 172 and 173, the compensator mat 24170 can comprise a bottom surface 24171 configured to abut the deck surface 24111 and, in addition, an attachment flange or rail 24174 extending from the bottom surface 24171 which can be configured to be securely received within a knife slot 24114 defined in the cartridge body 24110. The compensator mat 24170 can further comprise a plurality of packets 24172 which can extend transversely across the compensator mat 24170. In at least one such embodiment, each of the packets 24172 can be defined along a transverse axis which is transverse to and/or perpendicular to a longitudinal axis defined by the knife slot 24114, as illustrated in FIG. 176. In various embodiments, the compensator mat 24170 can comprise a plurality of layers between which the packets 24172 can be defined. In at least one such embodiment, the layers can be comprised of PDS and/or collagen, for example. In at least one embodiment, each packet 24172 can be configured to store one or more medicaments therein such as doxycycline, a coagulant, and/or an anti-microbial material, for example.

[0426] Referring again to FIG. 175, the tissue thickness compensator mat 24170 can be positioned relative to the cartridge body 24110 such that the packets 24172 overlie the staple cavities 21312 defined in the cartridge body 24110. More particularly, in at least one embodiment, each packet 24172 can be positioned and arranged such that it extends between the staples legs 21332 of a staple 21330. In various embodiments, the compensator mat 24170 can comprise a plurality of apertures and/or throughholes which can be configured to receive the ends of the staples 21330, for example. These throughholes can be positioned adjacent to the packets 24172, for example. As the staples 21330 are moved from an unfired position to a fired position, as illustrated in FIG. 175, the staples 21330 can be configured to capture the packets 24172 therein. In at least one such embodiment, the staples 21330 and the packets 24172 can be configured and arranged such that the packets 24172 are not punctured or ruptured while the staples 21330 are being fired. In such embodiments, the packets 24172 can provide a resilient or compressive pressure to the tissue T captured within the staples 21330 and can consume gaps between the tissue T and the staples 21330, for example. In various embodiments, referring again to FIG. 176, the packets 24172 can be incised by the cutting member 21380 as the cutting member 21380 is advanced through the knife slot 24114 defined in the cartridge body 24110, the tissue T, and/or the compensator mat 24170. The reader will note that the tissue thickness compensator 24120 is not depicted in FIGS. 175 and 176. Various embodiments are envisioned in which the staple cartridge 24100 includes the tissue thickness compensator mat 24170 and not the tissue thickness compensator 24120 while, in other embodiments, referring now to FIG. 177, the staple cartridge 24100 can include both the tissue thickness compensator mat 24170 and the tissue thickness compensator 24120, for example.

[0427] An alternative embodiment of a staple cartridge is illustrated in FIG. 178. In various embodiments, a circular staple cartridge 24200 can comprise a circular cartridge body 24210 including a plurality of staple cavities 21312 arranged in concentric circles, for example. In at least one such embodiment, the staple cartridge 24200 can further comprise a circular tissue thickness compensator mat 24270 positioned on the cartridge body 24210 wherein the compensator mat 24270 can comprise packets 24272 which extend radially outwardly, for example. In certain embodiments, similar to the above, the packets 24272 can extend in directions which overlie the staple cavities 21312 such that the packets 24272 can extend between the legs of staples 21330 positioned within the staple cavities 21312. Also similar to the above, the staples 21330 can be configured to capture the packets 24272 therein when the staples 21330 are fired from the staple cartridge 24200.

[0428] In various embodiments, referring now to FIG. 189, a staple cartridge 24300 can include a cartridge body 24310 and a tissue thickness compensator 24320 including a compensator body 24322 and a plurality of tubular members 24324 positioned within the compensator body 24322. In at least one such embodiment, the staple cartridge 24300 can further comprise a tissue thickness compensator layer, or sheet, 24370, for example, positioned intermediate the tissue thickness compensator 24320 and the cartridge body 24310. In certain embodiments, referring now to FIG. 179, a plurality of staple cartridges 24300 can be manufactured simultaneously utilizing a mold 24390. The mold 24390 can include a plurality of cavities 24391 which can each be configured to receive a cartridge body 24310 therein, as illustrated in FIG. 180. Thereafter, one or more large sheets of material comprising the tissue thickness compensator layer 24370 can be placed over the cartridge bodies 24310. In at least one embodiment, the mold 24390 can include a plurality of upwardly-extending support pins or posts 24392 wherein the sheets 24370 can be positioned against the posts 24392 and then pushed downwardly such that the posts 24392 can puncture the sheets 24370 as illustrated in FIGS. 181 and 183. In various embodiments, referring now to FIGS. 182 and 184, an elongate tube, or tubes, 24324 can be wound around and between the posts 24392 such that the tube 24324 passes over each cartridge body 24310 at least once. In at least one embodiment, the tube 24324 can be wound around and between the posts 24392 such that the tube 24324 passes over each cartridge body 24310 six times, for example. In certain embodiments, the tube 24324 can be permitted to rest on the sheets 24370 while, in certain other embodiments, the tube 24324 can be wound tightly around and between the posts 24392 such that the tube 24324 is taut and can be suspended above the sheets 24370. Once the tube 24324 has been suitably positioned, referring primarily to FIG. 185, a material comprising the compensator body 24322 can be poured into the mold 24390 on top of the sheets 24370. In at least one embodiment, the sheets 24370 can be configured to protect, or mask, the cartridge bodies 24310 and can prevent the compensator body material 24322 from entering into the staple cavities 21312 defined in the cartridge bodies 24310, for example. In various embodiments, a sufficient amount of compensator body material 24322 can be poured into the mold such that the compensator body material 24322 covers the elongate tube 24322.

[0429] In various embodiments, further to the above, the compensator body material 24322 can then be cured, solidified, and/or lyophilized, for example, to form the tissue thickness compensators 24320 on top of the cartridge bodies 24310. Thereafter, in at least one embodiment, referring now to FIG. 186, a cutting die 24395 can be utilized to cut the compensator body material 24322, the tissue thickness compensator sheets 24370, and the elongate tube 24322. In various embodiments, referring now to FIG. 187, the cutting die 24395 can comprise a plurality of cutting blades 24396 which can be configured to singulate and detach the tissue thickness compensators 24320 and the tissue thickness compensator sheets 24370 from one another. In certain embodiments, the cutting die 24395 can include a plurality of wells 24397 which can be configured to remove any excess material between the singulated tissue thickness compensators 24320 and the tissue thickness compensator sheets 24370, as illustrated in FIG. 188. In various embodiments, the cutting die 24935, and/or any other suitable die, can comprise one or more heating elements, for example, which can be configured to seal the ends and/or edges of the tissue thickness compensators 24320. In at least one embodiment, the tube 24324 can be filled with one or more fluids. In such embodiments, the cutting blades 24396 can be configured to incise the tube 24324 and, at the same time, seal the ends of the tube portions contained within the tissue thickness compensator 24320. Thereafter, the plurality of staple cartridges 24300 can be removed from the mold.

[0430] In various embodiments, referring now to FIGS. 190 and 191, a staple cartridge 24400 can comprise a cartridge body 24410 which can be configured to removably store a plurality of staples therein. In addition, the staple cartridge 24400 can further comprise a tissue thickness compensator 24420. In at least one embodiment, the tissue thickness compensator 24420 can include a compensator body comprised of a plurality of layers 24422 wherein, in various embodiments, the layers 24422 can be comprised of cellulose film, for example. As illustrated in FIG. 192, in various embodiments, a material 24424 can be positioned between two or more adjacent layers 24422 wherein the material 24424 can space the adjacent layers 24422 apart from each other. In at least one embodiment, the material 24424 can comprise a polyblend biomedics extrusion and, in various embodiments, the material 24424 can comprise a haemostatic material, an anti-inflammatory material, and/or an anti-biotic material, for example. In certain embodiments, referring now to FIG. 192, the material 24424 can be applied to a layer 24422 by a dispenser 24490 in a wave pattern, for example, wherein the wave pattern can be configured such that the material 24424 can be positioned over one or more staple cavities defined in the cartridge body 24410. In such embodiments, the material 24424 can be captured within staples ejected from the staple cavities and provide a resilient biasing force to tissue also captured within the staples. In any event, one or more of the layers 24422 can be vacuum formed and/or heat sealed, for example, over the material 24424 to create the tissue thickness compensator 24420. In certain embodiments, the tissue thickness compensator 22420 can then be cut to length. Various embodiments are envisioned in which a tissue thickness compensator 22420 is positioned against the deck surface of a staple cartridge and another tissue thickness compensator 22420 is positioned against the anvil.

[0431] In certain embodiments, referring now to FIG. 195, a staple cartridge 24600 can comprise one or more tissue thickness compensators 24620 positioned over a cartridge body 24610. Referring primarily to FIG. 194, each tissue thickness compensator 24620 can comprise a plurality of layers 24622 and a compressible, or collapsible, member 24624 positioned between the layers 24622. In various embodiments, the collapsible member 24624 can comprise a corrugated member which includes a plurality of pockets defined therein wherein, in at least one embodiment, one or more medicaments can be stored within the pockets. In at least one such embodiment, a first medicament can be placed within the pockets on a first side of the corrugated member and a second medicament can be placed within the pockets on a second side of the corrugated member, for example. In certain embodiments, the tissue thickness compensator 24620 can be formed when the layers 24622 and the compressible member 24624 are compressed together by rollers 24590, for example. With reference now to an embodiment depicted in FIG. 193, a tissue thickness compensator 24520 can be formed from a tube of material that is rolled into a partially flattened shape by rollers 24590, for example. In various embodiments, referring now to FIGS. 196 and 197, staples 21330 positioned within the cartridge body 24610 can be ejected therefrom such that the staples 21330 can capture at least a portion of a tissue thickness compensator 24620 therein. In such embodiments, the compressible member 24624 can be configured to apply a resilient biasing force against the tissue T which has also been captured within the staples 21330. In various embodiments, the layers 24622 of the tissue thickness compensator 24620 can also be configured to apply a resilient biasing force against the tissue T. In certain embodiments, the staples 21330 can puncture the pockets of the corrugated member 24624 and release the one or more medicaments contained therein.

[0432] The tissue thickness compensators described above may include substances therein. The substances may include coagulants, medications, and/or anti-inflammatories, for example. The substances may be liquids, but also may take other forms, such as solids and/or gels, for example. For surgical devices that include such tissue thickness compensators, it may be advantageous for the surgical device to include features that direct the substance out of the tissue thickness compensators. For example, the substance may be directed from the tissue thickness compensators toward incised and stapled tissue. In another example, a first tissue thickness compensator may include a first substance and a second thickness compensator may include a second substance, wherein the first and second substances may be mixed by the surgical device. As another example, the substances may be directed away from each other, toward a staple cartridge, and/or toward an anvil of the surgical device, for example.

[0433] FIGS. 61 and 62 illustrate a surgical stapling system that includes a cutting blade 19000 comprising a cutting edge 19016, a staple cartridge 19002, an anvil 19008, a first tissue thickness compensator 19004 positioned on the staple cartridge 19002, and a second tissue thickness compensator 19006 positioned on the anvil 19008. In use, the cutting blade 19000 is moved distally in the direction of arrow D to cut patient tissue T and the first and second tissue thickness compensators 19004 and 19006. In various embodiments, the first tissue thickness compensator 19004 comprises a substance S contained therein and the second tissue thickness compensator 19006 comprises a substance S′ contained therein. In various embodiments, the first tissue thickness compensator 19004 includes an encasement that includes the substance S therein. The encasement may include a film of material that is opened by the cutting blade 19000 cutting the film, wherein the substance S is released when the film is opened. The second tissue thickness compensator 19006 may include a similar encasement, and the second substance S′ may be released when the encasement of the second tissue thickness compensator 19006 is cut open by the cutting blade 19000. As the blade 19000 moves distally, guides 19030 and 19022 may direct or displace substances S and S′ from the first and second tissue thickness compensators 19004 and 19006, respectively. For example, substances S and S′ may be directed toward the incised tissue T. The blade 19000 may be coupled to a shaft 19012, which, in turn, may be connected to an actuating mechanism that moves the blade 19000 in the distal direction D and in a proximal direction indicated by arrow P.

[0434] A guide 19030 may direct the substance S from the first tissue thickness compensator 19004 towards the incised tissue T. A mirror-image of the guide 19030 may be positioned on an opposing face of the blade 19000. Guide 19030 may include two raised ridges 19032 and 19034 that define a channel C therebetween. A distal end 19035 of the channel C can be positioned proximate to the first tissue thickness compensator 19004 and a proximal end 19037 of the channel C can be positioned proximate to the tissue T when the surgical stapler is positioned against the tissue T. In use, as the cutting blade 19000 moves in the distal direction D, the substance S from the first tissue thickness compensator 19004 enters the channel C at distal end 19035, flows through the channel C, and exits the channel C at proximal end 19037 proximate to the tissue T.

[0435] A guide 19022 may direct substance S′ from the second tissue thickness compensator 19006 toward the incised tissue T. Guide 19022 includes a protrusion 19025 with an inclined surface 19023. As shown in FIG. 61, the protrusion 19025 may pierce or cut the second tissue thickness compensator 19006 to release the substance S′. As the blade 19000 moves distally D, the inclined surface 19025 can direct the substance S′ towards the tissue T.

[0436] Substances S and S′ may mix as they are directed towards the tissue T. The substances S and S′ may be different and may react when mixed. For example, substances S and S′ may react chemically when mixed to form a new substance S″. The new substance S″ may be, for example, a medication, an antibiotic, a coagulant, and/or any other suitable type of substance. After the blade 19000 has been suitably advanced in the distal direction D, the blade 19000 may return by moving proximally P wherein the proximal movement of the blade 19000 may further mix substances S and S′.

[0437] Alternatively, the guides 19022 and 19030 may be configured to direct substances S and S′ away from tissue T. For example, guide 19030 may be configured to direct substance S toward the staple cartridge 19002, and guide 19022 may be configured to direct substance S′ toward the anvil 19008. Such an arrangement may be advantageous, for example, if the first tissue thickness compensator 19004 is held to the staple cartridge 19002 by an adhesive at a junction 19005, for example, and if the second tissue thickness compensator 19906 is held to the anvil 19008 by an adhesive at a junction 19007, for example. The substances S and S′ may dissolve or neutralize the adhesives, thereby at least partially releasing the first and second tissue thickness compensators 19004 and 19006 from the staple cartridge 19002 and the anvil 19008, respectively.

[0438] FIG. 63 shows an alternative guide 19030′ in which a channel C′ is defined by a depression or groove in the surface of the blade 19014. The channel C′ may comprise a single channel or may comprise multiple channels.

[0439] FIGS. 64-67 illustrate another surgical stapling system that includes a cutting blade 19060 and a cutting edge 19056, a first tissue thickness compensator 19004, and a second tissue thickness compensator 19006. The blade 19060 may include a first protrusion 19062 on a first side of the blade 19060, wherein the first protrusion 19062 defines an orifice 19064 passing from the first side of the blade 19060 to a second side of the blade 19060. In various embodiments, the first protrusion 19062 and first orifice 19064 may be aligned with the first tissue thickness compensator 19004. In use, as the blade 19060 moves distally, at least a portion of the substance S in the first tissue thickness compensator 19004 can pass through the first orifice 19064. In various embodiments, contours of the first protrusion 19062 can direct the substance S to a second side of the blade 19060 and/or toward the tissue T.

[0440] The blade 19060 may also include a second protrusion 19066 on the second side of the blade 19060, wherein the second protrusion defines an orifice 19068 passing from the second side of the blade 19060 to the first side of the blade 19060. In various embodiments, the second protrusion 19066 and the second orifice may be aligned with the second tissue thickness compensator 19006. In use, as the blade 19060 moves distally, at least a portion of the substance S′ in the tissue thickness compensator 19006 can pass through the second orifice 19068. In various embodiments, contours of the second protrusion 19066 can direct the substance S′ to the first side of the blade 19060 and/or toward the tissue T.

[0441] Referring primarily to FIGS. 64 and 65, the shaft 19059 may include surface features, such as, for example, dimples 19070 that can increase turbulence and/or displacement of the substances S and S′. This increased turbulence and/or displacement can cause a greater portion of the substances S and S′ to come into contact with each other, for example. In at least one embodiment, the dimples 19070 can be positioned proximally with respect to the orifices 19064 and 19068. When the blade 19000 is being advanced distally, the dimples 19070 can be downstream of the orifices 19064 and 19068; however, when the blade 19000 is refracted proximally, the dimples 19070 can be upstream of the orifices 19064 and 19068.

[0442] FIGS. 68-70 illustrate another surgical stapler that includes a blade 19100 and a cutting edge 19108, a first tissue thickness compensator 19120, and a second tissue thickness compensator 19122. In various embodiments, the first tissue thickness compensator 19120 can comprise a first substance S and a second substance S′. For example, the first substance S can be contained in a first encasement, described above. The second substance S′ can be carried in a second encasement that can be proximate to and/or surrounding the first encasement. In various embodiments, the second tissue thickness compensator 19122 can comprise a third substance S″. In various embodiments, the second tissue thickness compensator 1922 can comprise a fourth substance S′″. The third substance S″ and the fourth substance S′″ may be carried in encasements, like the encasements described above. The blade 19100 may include a textured surface 19110 on a first side 19102 of the blade 19100 on which substances S, S′, S″, and S′″ can spread across. Another textured surface may be located on an opposing second side (not shown) of the blade 19100. The textured surface 19110 may comprise a series of disrupting features, such as, for example, grooves that are cut, scored, etched, and/or otherwise formed in the first surface 19102. The disrupting features also may comprise a series of raised features, such as raised ridges, on the first surface 19102, for example. As shown in FIGS. 68-70, the disrupting features of the textured surface 19110 may include a regularly repeating pattern of disrupting features. The disrupting features may also be placed in a non-repeating pattern or randomly placed.

[0443] The blade 19100 may also include a second surface 19104 that is positioned proximally relative to the first surface 19102. In various embodiments, the second surface 19104 can be raised relative to the first surface 19102. A junction between the first surface 19102 and the second surface 19104 can define a third surface 19106, wherein the third surface 19106 may be positioned at an angle relative to a longitudinal axis of the blade 19100. In various embodiments, the motion of the blade 19100 in the distal direction D can result in a first end 19107 of the third surface 19106 leading ahead of a second end 19109 of the third surface 19106. As a result, as shown in FIG. 70, the third surface 19106 can cause the substances S and S′ from the first tissue thickness compensator 19120 to be directed toward the incised tissue T. A surface 19105, similar to the second surface 19104, may be located on the opposing second side of the blade 19100.

[0444] The blade 19100 shown in FIGS. 68-70 may be used in a surgical device that includes the first and second tissue thickness compensators 19004 and 19006 shown in FIGS. 61-67. As described above, the textured surface 19110 may distribute the substances S and S′ from respective tissue thickness compensators 19004 and 19006 on the first surface 19102 of the blade such that they may mix and can be positioned near the tissue T.

[0445] The blade 19100 shown in FIGS. 68-70 also may be used in a surgical device that includes the first tissue thickness compensator 19120 and the second tissue thickness compensator 19122 shown in FIGS. 68-70. The first tissue thickness compensator 19120 may include an interior portion 19121 that includes a first substance S. When the first tissue thickness compensator 19120 is cut by the cutting edge 19108 of the blade 19100, the substance S can be released from the interior portion 19121. As the blade 19100 moves relative to the tissue thickness compensator 19120, the substance S may be spread on the textured surface 19110 and the third surface 19106 can direct the substance S toward the tissue T. As described above, in various embodiments, the first tissue thickness compensator 19120 may include a second substance S′ outside of the interior portion 19121. When the first tissue thickness compensator 19120 is cut by the cutting edge 19108 of the blade 19100, both the first substance S and the second substance S′ may be distributed on the textured surface 19110. The distribution on the textured surface 19110 may cause the first substance S and the second substance S′ to mix. When mixed, the first substance S and the second substance S′ may react, such as, for example, chemically reacting to form a new substance. The third surface 19106 may direct the first substance S and the second substance S′ towards the tissue. As described above, in various embodiments, the second tissue thickness compensator 19122 may include a third substance S″. When the second tissue thickness compensator 19122 is cut by the cutting edge 19108 of the blade 19100, the third substance S″ may be distributed on the textured surface 19110 where it may mix with the first substance S and/or the second substance S′ and be directed towards the tissue T. As described above, in various embodiments, the second tissue thickness compensator 19122 may include a fourth substance S′″. When the second tissue thickness compensator 19122 is cut by the cutting edge 19108 of the blade 19100, the third substance S″ and the fourth substance S′″ may be distributed on the textured surface 19110 where they may mix with the first substance S, the second substance S′ and/or each other and can be directed towards the tissue T.

[0446] In various embodiments, further to the above, a tissue thickness compensator can be comprised of a biocompatible material. The biocompatible material, such as, a foam, may comprise tackifiers, surfactants, fillers, cross-linkers, pigments, dyes, antioxidants and other stabilizers and/or combinations thereof to provide desired properties to the material. In certain embodiments, a biocompatible foam may comprise a surfactant. The surfactant may be applied to the surface of the material and/or dispersed within the material. Without wishing to be bound to any particular theory, the surfactant applied to the biocompatible material may reduce the surface tension of the fluids contacting the material. For example, the surfactant may reduce the surface tension of water contacting the material to accelerate the penetration of water into the material. In various embodiments, the water may act as a catalyst. The surfactant may increase the hydrophilicity of the material.

[0447] In various embodiments, the surfactant may comprise an anionic surfactant, a cationic surfactant, and/or a non-ionic surfactant. Examples surfactants include, but are not limited to polyacrylic acid, methalose, methyl cellulose, ethyl cellulose, propyl cellulose, hydroxy ethyl cellulose, carboxy methyl cellulose, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene stearyl ether, polyoxyethylene nonylphenyl ether, dialkylphenoxy poly(ethyleneoxy) ethanol, and polyoxamers, and combinations thereof. In at least one embodiment, the surfactant may comprise a copolymer of polyethylene glycol and polypropylene glycol. In at least one embodiment, the surfactant may comprise a phospholipid surfactant. The phospholipid surfactant may provide antibacterial stabilizing properties and/or disperse other materials in the biocompatible material.

[0448] In various embodiments, the tissue thickness compensator may comprise at least one medicament. The tissue thickness compensator may comprise one or more of the natural materials, non-synthetic materials, and/or synthetic materials described herein. In certain embodiments, the tissue thickness compensator may comprise a biocompatible foam comprising gelatin, collagen, hyaluronic acid, oxidized regenerated cellulose, polyglycolic acid, polycaprolactone, polyactic acid, polydioxanone, polyhydroxyalkanoate, poliglecaprone, and combinations thereof. In certain embodiments, the tissue thickness compensator may comprise a film comprising the at least one medicament. In certain embodiments, the tissue thickness compensator may comprise a biodegradable film comprising the at least one medicament. In certain embodiments, the medicament may comprise a liquid, gel, and/or powder. In various embodiments, the medicaments may comprise anticancer agents, such as, for example, cisplatin, mitomycin, and/or adriamycin.

[0449] In various embodiments, the tissue thickness compensator may comprise a biodegradable material to provide controlled elution of the at least one medicament as the biodegradable material degrades. In various embodiments, the biodegradable material may degrade may decompose, or loses structural integrity, when the biodegradable material contacts an activator, such as, for example an activator fluid. In various embodiments, the activator fluid may comprise saline or any other electrolyte solution, for example. The biodegradable material may contact the activator fluid by conventional techniques, including, but not limited to spraying, dipping, and/or brushing. In use, for example, a surgeon may dip an end effector and/or a staple cartridge comprising the tissue thickness compensator comprising the at least one medicament into an activator fluid comprising a salt solution, such as sodium chloride, calcium chloride, and/or potassium chloride. The tissue thickness compensator may release the medicament as the tissue thickness compensator degrades. In certain embodiments, the elution of the medicament from the tissue thickness compensator may be characterized by a rapid initial elution rate and a slower sustained elution rate.

[0450] In various embodiments, a tissue thickness compensator, for example, can be comprised of a biocompatible material which may comprise an oxidizing agent. In various embodiments, the oxidizing agent may an organic peroxide and/or an inorganic peroxide. Examples of oxidizing agents may include, but are not limited to, hydrogen peroxide, urea peroxide, calcium peroxide, and magnesium peroxide, and sodium percarbonate. In various embodiments, the oxidizing agent may comprise peroxygen-based oxidizing agents and hypohalite-based oxidizing agents, such as, for example, hydrogen peroxide, hypochlorous acid, hypochlorites, hypocodites, and percarbonates. In various embodiments, the oxidizing agent may comprise alkali metal chlorites, hypochlorites and perborates, such as, for example, sodium chlorite, sodium hypochlorite and sodium perborate. In certain embodiments, the oxidizing agent may comprise vanadate. In certain embodiments, the oxidizing agent may comprise ascorbic acid. In certain embodiments, the oxidizing agent may comprise an active oxygen generator. In various embodiments, a tissue scaffold may comprise the biocompatible material comprising an oxidizing agent.

[0451] In various embodiments, the biocompatible material may comprise a liquid, gel, and/or powder. In certain embodiments, the oxidizing agent may comprise microparticles and/or nanoparticles, for example. For example, the oxidizing agent may be milled into microparticles and/or nanoparticles. In certain embodiments, the oxidizing agent may be incorporated into the biocompatible material by suspending the oxidizing agent in a polymer solution. In certain embodiments, the oxidizing agent may be incorporated into the biocompatible material during the lyophylization process. After lyophylization, the oxidizing agent may be attached to the cell walls of the biocompatible material to interact with the tissue upon contact. In various embodiments, the oxidizing agent may not be chemically bonded to the biocompatible material. In at least one embodiment, a percarbonate dry power may be embedded within a biocompatible foam to provide a prolonged biological effect by the slow release of oxygen. In at least one embodiment, a percarbonate dry power may be embedded within a polymeric fiber in a non-woven structure to provide a prolonged biological effect by the slow release of oxygen. In various embodiments, the biocompatible material may comprise an oxidizing agent and a medicament, such as, for example, doxycycline and ascorbic acid.

[0452] In various embodiments, the biocompatible material may comprise a rapid release oxidizing agent and/or a slower sustained release oxidizing agent. In certain embodiments, the elution of the oxidizing agent from the biocompatible material may be characterized by a rapid initial elution rate and a slower sustained elution rate. In various embodiments, the oxidizing agent may generate oxygen when the oxidizing agent contacts bodily fluid, such as, for example, water. Examples of bodily fluids may include, but are not limited to, blood, plasma, peritoneal fluid, cerebral spinal fluid, urine, lymph fluid, synovial fluid, vitreous fluid, saliva, gastrointestinal luminal contents, and/or bile. Without wishing to be bound to any particular theory, the oxidizing agent may reduce cell death, enhance tissue viability and/or maintain the mechanical strength of the tissue to tissue that may be damaged during cutting and/or stapling. In various embodiments, the biocompatible material may comprise at least one microparticle and/or nanoparticle. The biocompatible material may comprise one or more of the natural materials, non-synthetic materials, and synthetic materials described herein. In various embodiments, the biocompatible material may comprise particles having a mean diameter of about 10 nm to about 100 nm and/or about 10 μm to about 100 μm, such as, for example, 45-50 nm and/or 45-50 μm. In various embodiments, the biocompatible material may comprise biocompatible foam comprising at least one microparticle and/or nanoparticle embedded therein. The microparticle and/or nanoparticle may not be chemically bonded to the biocompatible material. The microparticle and/or nanoparticle may provide controlled release of the medicament. In certain embodiments, the microparticle and/or nanoparticle may comprise at least one medicament. In certain embodiments, the microparticle and/or nanoparticle may comprise a hemostatic agent, an anti-microbial agent, and/or an oxidizing agent, for example. In certain embodiments, the tissue thickness compensator may comprise a biocompatible foam comprising an hemostatic agent comprising oxidized regenerated cellulose, an anti-microbial agent comprising doxycline and/or Gentamicin, and/or an oxidizing agent comprising a percarbant. In various embodiments, the microparticle and/or nanoparticle may provide controlled release of the medicament up to three days, for example.

[0453] In various embodiments, the microparticle and/or nanoparticle may be embedded in the biocompatible material during a manufacturing process. For example, a biocompatible polymer, such as, for example, a PGA/PCL, may contact a solvent, such as, for example, dioxane to form a mixture. The biocompatible polymer may be ground to form particles. Dry particles, with or without ORC particles, may be contacted with the mixture to form a suspension. The suspension may be lyophilized to form a biocompatible foam comprising PGA/PCL having dry particles and/or ORC particles embedded therein.

[0454] In various embodiments, the tissue thickness compensators or layers disclosed herein can be comprised of an absorbable polymer, for example. In certain embodiments, a tissue thickness compensator can be comprised of foam, film, fibrous woven, fibrous non-woven PGA, PGA/PCL (Poly(glycolic acid-co-caprolactone)), PLA/PCL (Poly(lactic acid-co-polycaprolactone)), PLLA/PCL, PGA/TMC (Poly(glycolic acid-co-trimethylene carbonate)), PDS, PEPBO or other absorbable polyurethane, polyester, polycarbonate, Polyorthoesters, Polyanhydrides, Polyesteramides, and/or Polyoxaesters, for example. In various embodiments, a tissue thickness compensator can be comprised of PGA/PLA (Poly(glycolic acid-co-lactic acid)) and/or PDS/PLA (Poly(p-dioxanone-co-lactic acid)), for example. In various embodiments, a tissue thickness compensator can be comprised of an organic material, for example. In certain embodiments, a tissue thickness compensator can be comprised of Carboxymethyl Cellulose, Sodium Alginate, Cross-linked Hyaluronic Acid, and/or Oxidized regenerated cellulose, for example. In various embodiments, a tissue thickness compensator can comprise a durometer in the 3-7 Shore A (30-50 Shore OO) ranges with a maximum stiffness of 15 Shore A (65 Shore 00), for example. In certain embodiments, a tissue thickness compensator can undergo 40% compression under 3 lbf load, 60% compression under 6 lbf load, and/or 80% compression under 20 lbf load, for example. In certain embodiments, one or more gasses, such as air, nitrogen, carbon dioxide, and/or oxygen, for example, can be bubbled through and/or contained within the tissue thickness compensator. In at least one embodiment, a tissue thickness compensator can comprise beads therein which comprise between approximately 50% and approximately 75% of the material stiffness comprising the tissue thickness compensator.

[0455] In various embodiments, a tissue thickness compensator can comprise hyaluronic acid, nutrients, fibrin, thrombin, platelet rich plasma, Sulfasalazine (Azulfidine®−5ASA+Sulfapyridine diazo bond))−prodrug−colonic bacterial (Azoreductase), Mesalamine (5ASA with different prodrug configurations for delayed release), Asacol® (5ASA+Eudragit-S coated−pH>7 (coating dissolution)), Pentasa® (5ASA+ethylcellulose coated−time/pH dependent slow release), Mesasal® (5ASA+Eudragit-L coated−pH>6), Olsalazine (5ASA+5ASA−colonic bacterial (Azoreductase)), Balsalazide (5ASA+4-Aminobenzoyl-B-alanine)-colonic bacterial (Azoreductase)), Granulated mesalamine, Lialda (delay and SR formulation of mesalamine), HMPL-004 (herbal mixture that may inhibit TNF-alpha, interleukin-1 beta, and nuclear-kappa B activation), CCX282-B (oral chemokine receptor antagonist that interferes with trafficking of T lymphocytes into the intestinal mucosa), Rifaximin (nonabsorbable broad-spectrum antibiotic), Infliximab, murine chymieric (monoclonal antibody directed against TNF-alpha-approved for reducing signs/symptoms and maintaining clinical remission in adult/pediatric patients with moderate/severe luminal and fistulizing Crohn's disease who have had inadequate response to conventional therapy), Adalimumab, Total Human IgG1 (anti-TNF-alpha monoclonal antibody—approved for reducing signs/symptoms of Crohn's disease, and for the induction and maintenance of clinical remission in adult patients with moderate/severe active Crohn's disease with inadequate response to conventional therapies, or who become intolerant to Infliximab), Certolizumab pegoll, humanized anti-TNF FAB′ (monoclonal antibody fragment linked to polyethylene glycol—approved for reducing signs/symptoms of Crohn's disease and for the induction and maintenance of response in adult patients w/moderate/severe disease with inadequate response to conventional therapies), Natalizumab, First non-TNF-alpha inhibitor (biologic compound approved for Crohn's disease), Humanized monoclonal IgG4 antibody (directed against alpha-4 integrin—FDA approved for inducing and maintaining clinical response and remission in patients with moderate/severe disease with evidence of inflammation and who have had inadequate response to or are unable to tolerate conventional Crohn's therapies and inhibitors of TNF-alpha), concomitant Immunomodulators potentially given with Infliximab, Azathioprine 6-Mercaptopurine (purine synthesis inhibitor—prodrug), Methotrexate (binds dihydrofolate reductase (DHFR) enzyme that participates in tetrahydrofolate synthesis, inhibits all purine synthesis), Allopurinol and Thioprine therapy, PP1, H2 for acid suppression to protect the healing line, C-Diff-Flagyl, Vancomycin (fecal translocation treatment; probiotics; repopulation of normal endoluminal flora), and/or Rifaximin (treatment of bacterial overgrowth (notably hepatic encephalopathy); not absorbed in GI tract with action on intraluminal bacteria), for example.

[0456] As described herein, a tissue thickness compensator can compensate for variations in the thickness of tissue that is captured within the staples ejected from a staple cartridge and/or contained within a staple line, for example. Stated another way, certain staples within a staple line can capture thick portions of the tissue while other staples within the staple line can capture thin portions of the tissue. In such circumstances, the tissue thickness compensator can assume different heights or thicknesses within the staples and apply a compressive force to the tissue captured within the staples regardless of whether the captured tissue is thick or thin. In various embodiments, a tissue thickness compensator can compensate for variations in the hardness of the tissue. For instance, certain staples within a staple line can capture highly compressible portions of the tissue while other staples within the staple line can capture portions of the tissue which are less compressible. In such circumstances, the tissue thickness compensator can be configured to assume a smaller height within the staples that have captured tissue having a lower compressibility, or higher hardness, and, correspondingly, a larger height within the staples that have captured tissue having a higher compressibility, or lower hardness, for example. In any event, a tissue thickness compensator, regardless of whether it compensates for variations in tissue thickness and/or variations in tissue hardness, for example, can be referred to as a ‘tissue compensator’ and/or as a ‘compensator’, for example.

[0457] The devices disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. In either case, however, the device can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the device, followed by cleaning or replacement of particular pieces, and subsequent reassembly. In particular, the device can be disassembled, and any number of the particular pieces or parts of the device can be selectively replaced or removed in any combination. Upon cleaning and/or replacement of particular parts, the device can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of a device can utilize a variety of techniques for disassembly, cleaning/replacement, and reassembly. Use of such techniques, and the resulting reconditioned device, are all within the scope of the present application.

[0458] Preferably, the invention described herein will be processed before surgery. First, a new or used instrument is obtained and if necessary cleaned. The instrument can then be sterilized. In one sterilization technique, the instrument is placed in a closed and sealed container, such as a plastic or TYVEK bag. The container and instrument are then placed in a field of radiation that can penetrate the container, such as gamma radiation, x-rays, or high-energy electrons. The radiation kills bacteria on the instrument and in the container. The sterilized instrument can then be stored in the sterile container. The sealed container keeps the instrument sterile until it is opened in the medical facility.

[0459] Any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

[0460] While this invention has been described as having exemplary designs, the present invention may be further modified within the spirit and scope of the disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.