In various embodiments, a tissue thickness compensator can comprise a plurality of fibers. In at least one embodiment, such fibers can include a plurality of first fibers comprised of a first material and a plurality of second fibers comprised of a second material. A tissue thickness compensator can comprise a plurality of layers wherein each layer can be comprised of one or more medicaments. Certain embodiments are disclosed herein for manufacturing a tissue thickness compensator comprising fibers, for example.