A surgical instrument comprising: (a) a handle portion and a shaft, the shaft housing a firing bar; (b) a stapling and severing assembly (41, 48, 132) at the distal end of the firing bar, wherein the firing bar and the stapling and severing assembly (41, 48, 132) are operable to translate longitudinally responsive to a longitudinal closing motion produced by the handle portion and the shaft, (c) an end effector connected to the handle portion, the end effector comprising an anvil (123, 145), a lower jaw and a staple cartridge, the anvil (123, 145) defining a recess (122, 144) and a slot in communication with the recess, the lower jaw being configured to receive the staple cartridge, which comprises: (d) a housing, a plurality of staples disposed in the housing; and (e) a deck disposed over the plurality of staples, the deck defining apertures, each aperture being substantially disposed over each staple; and (f) a biocompatible material (120, 142) configured for receipt within the recess (122, 144) in the anvil (123, 145); (g) wherein the firing bar is operable to translate longitudinally between the anvil and the cartridge and through the slot to sever the material and to drive the staples towards the anvil (123, 145) and form the staples against the anvil (123, 145) in response to the longitudinal closing motion when the lower jaw with the cartridge is in a closed position; characterized in that: the biocompatible material (120, 142) includes: a top portion (128, 158) comprised of a ceramic or a metal; and a bottom portion (130, 160) comprising a matrix, for example having a plurality of openings therein, a foam, for example an open cell foam or a closed cell foam, a fabric pad, a fibrous pad, a mesh and/or an adhesive; and the stapling and severing assembly comprises an upper portion configured to sever the bottom portion (130, 160) in the recess (122, 144) in the anvil (123, 145) as the stapling and severing assembly (41, 48, 132) responds to the longitudinal closing motion. (a) a handle portion and a shaft, the shaft housing a firing bar; (b) a stapling and severing assembly (41, 48, 132) at the distal end of the firing bar, wherein the firing bar and the stapling and severing assembly (41, 48, 132) are operable to translate longitudinally responsive to a longitudinal closing motion produced by the handle portion and the shaft, (c) an end effector connected to the handle portion, the end effector comprising an anvil (123, 145), a lower jaw and a staple cartridge, the anvil (123, 145) defining a recess (122, 144) and a slot in communication with the recess, the lower jaw being configured to receive the staple cartridge, which comprises: (d) a housing, a plurality of staples disposed in the housing; and (e) a deck disposed over the plurality of staples, the deck defining apertures, each aperture being substantially disposed over each staple; and (f) a biocompatible material (120, 142) configured for receipt within the recess (122, 144) in the anvil (123, 145); (g) wherein the firing bar is operable to translate longitudinally between the anvil and the cartridge and through the slot to sever the material and to drive the staples towards the anvil (123, 145) and form the staples against the anvil (123, 145) in response to the longitudinal closing motion when the lower jaw with the cartridge is in a closed position; characterized in that: the biocompatible material (120, 142) includes: a top portion (128, 158) comprised of a ceramic or a metal; and a bottom portion (130, 160) comprising a matrix, for example having a plurality of openings therein, a foam, for example an open cell foam or a closed cell foam, a fabric pad, a fibrous pad, a mesh and/or an adhesive; and the stapling and severing assembly comprises an upper portion configured to sever the bottom portion (130, 160) in the recess (122, 144) in the anvil (123, 145) as the stapling and severing assembly (41, 48, 132) responds to the longitudinal closing motion. the biocompatible material (120, 142) includes: a top portion (128, 158) comprised of a ceramic or a metal; and a bottom portion (130, 160) comprising a matrix, for example having a plurality of openings therein, a foam, for example an open cell foam or a closed cell foam, a fabric pad, a fibrous pad, a mesh and/or an adhesive; and a top portion (128, 158) comprised of a ceramic or a metal; and a bottom portion (130, 160) comprising a matrix, for example having a plurality of openings therein, a foam, for example an open cell foam or a closed cell foam, a fabric pad, a fibrous pad, a mesh and/or an adhesive; and the stapling and severing assembly comprises an upper portion configured to sever the bottom portion (130, 160) in the recess (122, 144) in the anvil (123, 145) as the stapling and severing assembly (41, 48, 132) responds to the longitudinal closing motion.