Oxidation-resistant and wear-resistant polyethylenes for human joint replacements and methods for making them

摘要

The present invention presents methods for making oxidation-resistant and wear-resistant polyethylenes and medical implants made therefrom. Preferably, the implants are components of prosthetic joints, e.g., a bearing component of an artificial hip or knee joint. The resulting oxidation-resistant and wear-resistant polyethylenes and implants are also disclosed.

主权项

1. A method for producing a wear-resistant and oxidation-resistant medical implant of a joint prosthesis, said method comprising the steps of:
(I) providing an oxidation-resistant medical implant of a joint prosthesis comprising a polyethylene component; and (II) irradiating the oxidation-resistant medical implant at a radiation dose of above 5 Mrad to about 25 Mrad so as to crosslink the implant thereby improving its wear resistance, without thermally treating the implant to extinguish free radicals in the irradiated and crosslinked implant during or subsequent to irradiating the oxidation-resistant implant; wherein the oxidation-resistant implant contains an antioxidant rendering it resistant to oxidation caused by free radicals generated by the irradiation of step (II); and the irradiated oxidation-resistant implant possesses a gel content of between about 95% to about 99%.