Selectively demineralized bone-derived implants are provided. In one
embodiment, a bone sheet for implantation includes a demineralized field
surrounding mineralized regions. In another embodiment, a bone defect
filler includes a demineralized cancellous bone section in a first
geometry. The first geometry is compressible and dryable to a second
geometry smaller than the first geometry, and the second geometry is
expandable and rehydratable to a third geometry larger than the second
geometry.