The effect of different sterilization methods on the mechanical strength of magnesium based implant materials

Abstract

The research on the development and characterization of potential magnesium biomaterials is a steadily expanding. Commonly, implants present a high risk of infection for their recipients. For this reason, a pre-operative sterilizing process is required. Due to the temperatures and media which are used while sterilizing, effects may occur which cause a change in the mechanical strength of certain magnesium alloys. Four commonly used sterilization methods (autoclave sterilization, dry heat sterilization, gamma sterilization and ethylene oxide sterilization) were investigated to gain information about their influences on the quasi-static mechanical behavior of LAE442 (Mg 90m.%, Li 4m.%, Al 4m.%, RE 2m.%), MgCa0.8 (Mg 99.2m.%, Ca 0.8m.%) magnesium alloys as well as pure magnesium. The mechanical properties exhibited by the sterilized and non-sterilized alloys refer to susceptibilities of the mechanical strengths to the investigated sterilization methods. Such susceptibilities appear to be dependent on the combination of alloy and method of sterilization. However, the maximum changes in mechanical strength appear in the range of ±10%. Within this study, ETO sterilization caused the least changes in the mechanical strength of the alloys and appears to be the best performer. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.