Superhard Nanocrystalline Coated Prosthesis

超硬纳米晶涂层假体

• 批准号: 6773253
• 负责人: ERIC J TOBIN
• 金额: $ 36.93万
• 依托单位: SPIRE CORPORATION
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-30 至 2006-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6773253
• 关键词: adhesions; alloys; atomic force microscopy; bioengineering /biomedical engineering; biomaterial development /preparation; biomaterial evaluation; biomaterial interface interaction; chromium; cobalt; hardness; hip prosthesis; metals; nanotechnology; polyethylenes; surface coating

DESCRIPTION (provided by applicant): Nanocrystalline homometallic (same as the substrate and without interface) coatings will be developed to reduce wear of ultra-high molecular weight polyethylene (UHMWPE) in orthopedic prostheses. UHMWPE wear is a primary cause of prosthesis failure, and roughness of the mating Co-Cr surface has been identified as a major contributing factor to UHMWPE wear. Third-body wear particles, such as bone cement constituents, scratch the articulating surface, roughening it and accelerating UHMWPE wear. Attempts to apply conventional hard ceramic coatings to the metallic surfaces have not been successful because of difficulties in achieving adequate adhesion due to dissimilarity of coating and substrate materials and thermal and lattice mismatches. We have demonstrated, for the first time, that nanocrystalline (3-40 nm grains) Co-Or deposited onto Co-Cr-Mo substrates possesses hardness close to that of some ceramics (18-26 GPa, 400% increase), without the associated problems with adhesion to metallic substrates. (Similar results have also been obtained for Ti and stainless steel). In post Phase I work, we have demonstrated uniform deposition of superhard homometallic coatings onto Co-Cr femoral hip heads. Ongoing hip simulation tests have demonstrated up to 75% reduction in UHWMPE wear against homometallic Co-Or femoral heads vs. uncoated Co-Cr. Additionally, atomic force microscopy shows that the homometallic coatings retain the same low surface roughness as the original, highly polished Co-Cr. These results clearly demonstrate feasibility of the proposed technology. Phase 2 will optimize the processes involved in deposition of homometallic coatings and evaluate them in Hip Simulation tests, which will be done by Stephen Li at the Medical Device Testing and Innovation and a major Orthopedic Company.

描述（由申请人提供）：将开发纳米晶同质金属（与基材相同且无界面）涂层，以减少矫形假体中超高分子量聚乙烯（UHMWPE）的磨损。 UHMWPE 磨损是假体失效的主要原因，而配合 Co-Cr 表面的粗糙度已被确定为 UHMWPE 磨损的主要影响因素。第三体磨损颗粒（例如骨水泥成分）会划伤关节表面，使其变得粗糙并加速 UHMWPE 磨损。将传统的硬陶瓷涂层施加到金属表面的尝试尚未成功，因为由于涂层和基材材料的不同以及热和晶格失配而难以获得足够的附着力。 我们首次证明，沉积在 Co-Cr-Mo 基材上的纳米晶（3-40 nm 晶粒）Co-Or 具有接近某些陶瓷的硬度（18-26 GPa，增加 400%），并且不存在与金属基材粘附的相关问题。 （对于钛和不锈钢也得到了类似的结果）。在第一阶段的后期工作中，我们已经证明了超硬同质金属涂层在钴铬股骨髋头上的均匀沉积。正在进行的髋部模拟测试表明，与未涂层 Co-Cr 相比，同质金属 Co-Or 股骨头的 UHWMPE 磨损最多可减少 75%。此外，原子力显微镜显示同金属涂层保留了与原始高度抛光的钴铬合金相同的低表面粗糙度。这些结果清楚地证明了所提出技术的可行性。 第二阶段将优化同质金属涂层沉积过程，并在髋关节模拟测试中对其进行评估，该测试将由医疗器械测试与创新公司和一家大型骨科公司的 Stephen Li 完成。