영문제목 New poly Crosslinked poly

초록

Ultra high molecular weight polyethylene (UHMWPE) has been the material of choice for bearing surfaces in total joint replacements for over 30 years. However, during the last 10 years a large number of reports of its failures have been published. The major factor responsible for these failures was oxidative degradation induced by sterilization with gamma irradiation. The majority of UHMWPE components used in prostheses over the past three decades were sterilized using 2.5 to 4 Mrads of gamma radiation, with the implant packaged in air during the sterilization and, in some cases, during several years or more of shelf storage prior to clinical use. Clinical follow-ups, involving thousands of these gamma-sterilized implants, and retrieval analysis have established that gamma-sterilization had both good and bad effects on the polyethylene. One important benefit was that the moderate level of crosslinking, induced by the gamma radiation had the potential to improve the wear resistance of the polyethylene.