Aging Resistant Ceramics for Total Hip Arthroplasty

全髋关节置换术用耐老化陶瓷

• 批准号: 6644503
• 负责人: R LAKSHMINARAYANAN
• 金额: $ 9.94万
• 依托单位: SINTX TECHNOLOGIES, INC.
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-18 至 2003-10-17
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6644503
• 关键词: aging; aluminum; arthroplasty; biomaterial compatibility; biomaterial development /preparation; biomaterial evaluation; ceramics; cerium; hip; zirconium

DESCRIPTION (provided by applicant): Zirconia bio-ceramics (e.g. Prozyr) have the highest toughness and strength compared to other bio-ceramics such as alumina (e.g. Biolox) or zirconia-toughened alumina (Biolox-Delta). However, as highlighted by the recent recall of St. Gobain zirconia heads, a critical need remains to develop bio-ceramics with both significantly reduced wear characteristics and reduced fracture risk in-vivo. Theoretical calculations and practical demonstration show that damage resistance in many ceramic systems has been significantly improved by imparting insurface compression. This mechanism will be employed by providing a layered composite structure to make ceramics with significantly enhanced wear resistance. A novel doping strategy will be used to improve aging resistance of zirconia. By these enhancements the investigators propose to demonstrate feasibility and merits of advanced zirconia toughened alumina (ZTA) composites as a replacement for CoCr femoral heads and currently used alumina and zirconia femoral heads. This should lead to a simultaneous dramatic reduction in wear and catastrophic failure risk, thereby addressing and eliminating one of the most important clinical problems in total-hip arthroplasty (THA). In this phase I project, the aging resistance of the zirconia will be improved by adding suitable dopants to shift the martensitic start temperature far below in-vivo temperatures. Amount of monoclinic content in the matrix measured using XRD, after autoclaving will be the indicator of the aging resistance. The strength of this aging resistant zirconia is further improved by a suitable choice of the matrix. In addition by careful design of surface compression further improvement in strength and fracture toughness can be attained. The strength and fracture toughness will be measured using ASTM protocols C-1161 and E-399. Finally, wear performance will be evaluated using pin-on-disk wear tester and compared to the performance of currently available zirconia and alumina materials used for femoral heads. The three-step characterization will establish the superior performance of ACe-TZP materials over the currently existing alumina and zirconia materials for THA.

描述（由申请人提供）：与其他生物陶瓷（例如氧化铝（例如Biolox）或氧化氧化铝（Biolox-delta））相比，与其他生物陶瓷相比，氧化氧化生物陶瓷（例如Prozyr）具有最高的韧性和强度。然而，正如最近对圣戈巴因氧化锆头的回忆所强调的那样，发展生物陶瓷的重要需求仍然显着降低了磨损特性，并且体内骨折风险降低。 理论计算和实际演示表明，通过施加保险表压缩，许多陶瓷系统中的抗损伤性已得到显着改善。该机制将通过提供分层复合结构来使陶瓷具有显着增强的耐磨性。一种新型的兴奋剂策略将用于改善氧化锆的耐老化耐药性。通过这些增强功能，研究人员建议证明晚期氧化锆加氧化铝（ZTA）复合材料的可行性和优点，以替代COCR股骨头，目前使用了氧化铝和氧化氧化甲基股头。这将导致磨损和灾难性衰竭风险同时急剧降低，从而解决并消除全型临床置换术（THA）中最重要的临床问题之一。 在此I阶段项目中，通过添加合适的掺杂剂将马氏体起始温度转移到远低于体内温度的情况下，可以提高氧化锆的衰老抗性。使用XRD测量的基质中的单斜含量，在高压灭菌后将是衰老抗性的指标。通过合适的基质选择，这种耐老化的氧化锆的强度进一步提高了。此外，通过仔细设计表面压缩，可以实现强度和断裂韧性的进一步改善。强度和断裂韧性将使用ASTM方案C-1161和E-399测量。最后，将使用针孔磨损测试仪对磨损性能进行评估，并将其与当前可用的氧化锆和用于股骨头的氧化铝材料的性能进行比较。三步的特征将确定ACE-TZP材料的优越性能，而不是当前现有的氧化铝和氧化氧化铝材料。