The preferred method of crosslinking is by exposing the UHMWPE to ionizing radiation. 6,448,315), in attempts to improve wear resistance. also described that irradiation does not decrease the oxidation resistance of antioxidant-doped polyethylene. In another aspect, the invention provides methods of making a medical implant comprising: a) providing a polymeric material; b) consolidating the polymeric material; c) irradiating the consolidated polymeric material with ionizing radiation, thereby forming a consolidated and cross-linked polymeric material; d) machining the consolidated and cross-linked polymeric material, thereby forming a medical implant; and e) doping the medical implant with an antioxidant by diffusion, thereby forming an antioxidant-doped cross-linked medical implant.
The invention also provides methods of making antioxidant-doped medical implants, for example, doping of medical devices containing cross-linked UHMWPE with vitamin E by diffusion and materials used therein. Therefore, there is a need to either eliminate the residual free radicals or the oxidative effect of residual free radicals without melting. In another aspect, the invention provides methods of making a medical implant containing cross-linked polymeric material comprising: a) compression molding of polymeric material to another piece, thereby forming an interface and an interlocked hybrid material; b) doping the interlocked hybrid material with an antioxidant by diffusion; and c) irradiating the interlocked hybrid material by ionizing radiation, thereby forming a cross-linked and interlocked hybrid material.
The present invention relates to a laser irradiation method and using the method of laser irradiation device (laser irradiation apparatus including a laser oscillator and a laser beam emitted from the laser oscillator is irradiated object directed to an optical system).