A biodegradable, bioresorbable, three-dimensional template for repair and replacement of diseased or injured bone which provides mechanical strength to bone while also providing a guide for growth of bone tissue. Preferably, the template is formed of biodegradable materials, for example, poly(L-lactic acid), poly(D, L-lactic acid), poly (D, L-lactic-co-glycolic acid), poly (glycolic acid), poly (ε-caprolactone), polyortho esters, and polyanhydrides, and has the capacity of being rendered porous, either in vitro or in vivo. A pore-forming component, which may or may not be a polymeric material, is mixed within a continuous matrix formed of a biodegradable material, the pore-forming component having a rate of degradation which exceeds that of the matrix. Differential dissolution or biodegradation provides porosity to the template.