Abstract: This invention relates to biomechanical devices comprising a liquid sinterable metallic alloy, characterized by a multiphase, composite microstructure of isolated spherical grains approximately 50 microns in diameter distributed in an essentially nonporous matrix. The dental prosthetic devices include full-cast crowns, copings, pontics, inlays, onlays, and bridges. Other devices include reconstructive and orthopedic pieces. A method for fabricating a dental prosthetic device is also recited.

Abstract: A vacuum furnace for heating dental reconstructionproducts using sintered powder metal that includes a sealed vacuum tube made of a material having a relatively low thermal shock resistance characteristic. The vacuum tube is desirably relatively short. The vacuum tube chamber has a heating chamber and end seals for the vacuum tube have a maximum use temperature of less than 200.degree. C. Insulation is positioned around and connected to the tube proximate the ends of the tube, and heating elements are placed around the heating chamber in an annular insulation chamber formed in the insulation between the insulation and the vacuum tube. Opposed annular clearances extending to positions proximately spaced from the ends of the tube and opening to the central annular insulation chamber are formed between the insulation means and the vacuum tube. The insulation prevents heat from passing to the ends of the tube and overheating the seals there.

Abstract: A high strength porcelain dental prosthetic device, such as an infrastructure, inlay or onlay is formed directly from a dental porcelain fired at elevated temperatures of about 1000.degree. F. and above, under a pressure of about 10 to 1000 microns of Hg. A special furnace is devised which will achieve this pressure range in a rapid efficient manner. The resultant porcelain dental infrastructure has a high density, and the strength approaching that found in commercial cast ceramic restorations.

Abstract: An alloyed metal dental prosthetic device, such as a coping, of an alloy dental reconstructive element, is formed from a liquid phase sintered powdered metal alloy at elevated temperatures of about 1000.degree.-1300.degree. C. under a high level of vacuum of about 10 to 1000 microns of Hg. A special oven is devised which will achieve this high level of vacuum in a rapid efficient manner. The resultant metal prosthetic device has the density of at least that found in commercial cast prosthetic devices.