Abstract: A prefabricated medical implant made of polymeric material having increased wear resistance without substantially changing its ductility and other physical properties is described. The implant is formed by a method including the steps of heating a sealed, packaged, prefabricated implant, having a reduced oxygen atmosphere, to an elevated temperature below its annealing point at a predetermined rate and held at that temperature for a predetermined time. After this time the packaged implant, while being maintained in a predetermined temperature range, is irradiated with a predetermined amount of gamma radiation. After irradiation, the implant is permitted to cool at a predetermined rate. Thermal conductive and thermal insulation containers are also provided for holding the packaged implants during the process.

Abstract: Surface and near surface hardened medical implants are provided. These implants are fabricated from titanium alloys that contain an amount of zirconium sufficient to permit the formation of a significant amount of zirconium oxide at the surface of the implant to cause surface hardening. Further, the zirconium-containing titanium alloy implants are characterized in having an alloy core with an oxygen-rich layer surrounding the core, and a surface layer, overlying the oxygen-rich layer, including mixed oxides of the metals present in the alloy. A zirconium-rich interface may sometimes be present between the oxygen-rich layer and the mixed-oxide surface layer. The method of producing these surface hardened implants includes the steps of heating the implant in an oxygen containing environment at a temperature sufficient to allow oxygen to diffuse to and react with the implant surface and near surface.

Abstract: Apparatus and process for simultaneously milling, dehydrating and/or sterilizing a material by introducing the material into a chamber comprising rotating instruments while substantially simultaneously introducing a hot gas into the chamber. Gas and material are introduced tangentially to the chamber at points opposed from each other, and the gas and material both enter the chamber in the same direction as the rotating instruments.