Abstract: A moldable bone-implant material containing between about 65%-95% hard filler particles and a binder composed of between about 35%-5% of a biocompatible, biodegradable, thermoplastic polymer which has fluidic flow properties at or below about 60.degree. C. One preferred binder is polylactic acid having a molecular weight between about 400 and 5,000 daltons, and a preferred hard filler is hydroxylapatite. In use, the material is warmed to a temperature which allows molding, and the bone site is filled with the moldable material, which then forms a contour-fitting, semi-rigid implant. The implant retains its contour fit and acquires a rigid final state as the binder in the implant is gradually biodegraded and replaced through tissue ingrowth from the surrounding bone site.