nontoxic polymeric plastic medical implants for endosteal and periosteal applications such as filling bone defects , replacing entire bony parts , and tooth replacement either immediately after extraction or subsequent to healing , and a method of fabricating such implants to produce a porous surface having a predetermined pore size , pore depth , and degree of porosity . the method of fabrication of the porous portion of the implant involves adding sodium chloride crystals or other nontoxic leachable substance of controlled particle size corresponding to the desired pore size to a powdered polymer - liquid monomer mixture in relative amounts corresponding to the desired degree of porosity . after heat polymerization without an initiator , followed by abrasive removal of the resulting surface skin , the salt is leached from the plastic to provide said porosity . to obtain bone ingrowth in the case of intraosseous implantation , the pore size must be 200 - 400 microns , whereas pore size for soft tissue ingrowth should be 50 - 150 microns .