A method for forming a ceramic article useful as a bone substitute and having an outer surface defining a shape having a bulk volume and having open, interconnecting openings extending throughout the volume and opening through the surface, includes, providing an organic open-pore structure, coating surface of pores of the structure with a ceramic slip, pyrolyzing the organic structure to leave a ceramic structure having struts defining a plurality of interconnecting interstices, and providing within the interstices a porous osteoconductive composition exposed to the interconnecting openings. In a preferred embodiment, the ceramic slip includes a strong, supportive ceramic material and a separate osteoconductive material.