Fuchs S, Schmidt T, Haftka S, Jerosch J
Westfälische Wilhelms Universität Münster.
Biomed Tech (Berl). 1997 Jul-Aug;42(7-8):190-5.
We analysed the changes in crystallinity in sterilized and machined UHMWPE products used in the manufacture of total joint components. For this purpose, so-called DC measurements of absolute crystallinity and infrared spectroscopy for determining the relevant crystallinity were carried out. The DSC measurements are based on a further development of differential thermo-analysis (DTA), and a comparison of the melting enthalpy of an unknown material in comparison with known material. The results show particularly high values for gamma sterilized products, and the lowest values, i.e. the least brittleness, after sterilization with ETO. The crystallinity of the original material was 55%, that after gamma sterilized 56.5%, and after steam autoclaving 57.9%; after gamma sterilized in argon 56%, and after ETO sterilized 57.7%. During the period prior to the manufacture of the end product, a wide range of values is determinable. The average crystallinity of the end products varies between 55.4% and 61.6%. Among other things, changes in crystallinity during storage and after implantation must be taken into account. To summarize, we recommended ethylene oxide sterilization, after which the best values of crystallinity were seen in both semi-finished and finished products (prostheses).
我们分析了用于制造全关节组件的灭菌和加工超高分子量聚乙烯（UHMWPE）产品的结晶度变化。为此，进行了所谓的绝对结晶度的差示扫描量热法（DSC）测量以及用于测定相关结晶度的红外光谱分析。DSC测量基于差示热分析（DTA）的进一步发展，以及将未知材料的熔化焓与已知材料进行比较。结果显示，γ射线灭菌产品的值特别高，而环氧乙烷（ETO）灭菌后的值最低，即脆性最小。原始材料的结晶度为55%，γ射线灭菌后为56.5%，蒸汽高压灭菌后为57.9%；在氩气中γ射线灭菌后为56%，ETO灭菌后为57.7%。在最终产品制造之前的阶段，可以确定很宽的数值范围。最终产品的平均结晶度在55.4%至61.6%之间变化。此外，必须考虑储存期间和植入后结晶度的变化。总之，我们推荐环氧乙烷灭菌，之后在半成品和成品（假体）中都能看到最佳的结晶度值。
