A staple cartridge for use with a surgical stapling apparatus includes a cartridge body including a tissue contacting surface defining a plurality of staple retaining slots, a staple disposed within each staple retaining slot of the cartridge body, and a substantially circular buttress. The buttress includes an inner portion, an outer portion, and a middle portion extending between the inner portion and the outer portion. At least one stiffened region joins the buttress to the tissue contacting surface of the cartridge body. The inner portion, the middle portion, the outer portion, and the at least one stiffened region are all formed from a common material.