Exponent, Inc., Philadelphia, Pennsylvania 19104, USA.
J Biomed Mater Res B Appl Biomater. 2010 May;93(2):442-7. doi: 10.1002/jbm.b.31601.
The objectives of this study were three-fold: (1) to determine the applicability of the small punch test to characterize Bionate 80A polycarbonate urethane (PCU) acetabular implants; (2) to evaluate the susceptibility of PCU acetabular implants to exhibit degradation of mechanical behavior following gamma irradiation in air and accelerated aging; and (3) to compare the oxidation of gamma-air sterilized PCU following accelerated aging and 5 years of natural shelf aging. In addition to attenuated total reflectance-Fourier transform infrared spectroscopy, we also adapted a miniature specimen mechanical test, the small punch test, for the deformable PCU cups. Accelerated aging was performed using ASTM F2003, a standard test that represents a severe oxidative challenge. The results of this study suggest that the small punch test is sufficiently sensitive and reproducible to discriminate slight differences in the large-deformation mechanical behavior of Bionate 80A following accelerated aging. The gamma-air sterilized PCU had a reduction of 9% in ultimate load after aging. Five years of shelf aging had little effect on the mechanical properties of the PCU. Overall, our findings suggest that the Bionate 80A material has greater oxidative stability than ultra-high molecular weight polyethylene following gamma irradiation in air and exposure to a severe oxidative challenge.
(1)确定小冲孔试验在表征 Bionate 80A 聚碳酸酯氨酯(PCU)髋臼植入物方面的适用性；(2)评估 PCU 髋臼植入物在空气中伽马辐照和加速老化后表现出机械性能下降的敏感性；(3)比较加速老化和 5 年自然货架老化后经伽马空气消毒的 PCU 的氧化情况。除衰减全反射傅里叶变换红外光谱外，我们还采用微型试件力学试验，即小冲孔试验，对可变形 PCU 杯进行了测试。加速老化采用 ASTM F2003 进行，这是一项代表严重氧化挑战的标准试验。本研究结果表明，小冲孔试验足够灵敏且可重复，可区分 Bionate 80A 在加速老化后的大变形力学行为的细微差异。伽马空气消毒的 PCU 在老化后极限载荷降低了 9%。5 年货架老化对 PCU 的力学性能影响很小。总体而言，我们的研究结果表明，与超高分子量聚乙烯相比，Bionate 80A 材料在空气中伽马辐照和暴露于严重氧化挑战后具有更高的氧化稳定性。
