Implantable materials for use with end effectors like surgical stapling devices, and methods associated with the operation of such end effectors, are provided herein. In one exemplary embodiment, a tissue reinforcement material is releasably retained on a portion of a surgical stapler end effector for delivery to tissue upon deployment of staples. The tissue reinforcement material comprises a plurality of fibers having an arrangement configured to compress and seal around a fastener component inserted therethrough. Other implants, devices, and methods for surgical stapling are also provided.