CVD Zirconia Coating on CO-CR Orthopedic Implants

Long-term performance of orthopaedic joint prostheses is now limited by wear. Surface coatings have been shown to be effective in reducing this wear, but each metal alloy system requires a different treatment. Spire's ion implantation process has been used effectively to reduce titanium wear through direct treatment of titanium surfaces and to reduce UHMWPE wear through treatment of mating Co-Cr surfaces. This proposal strives to continue Spire's leadership in this field by combining the beneficial properties of the metal with the desired wear properties of a ceramic. Hardened ceramic coatings will reduce wear and will have immediate commercial impact with significant benefits to younger patients who would have to use these devices for extended periods. Zirconia is a biocompatible, hard ceramic with good wear and lubricity. It can be uniformly applied on intricate surfaces by chemical vapor deposition (CVD) at low temperatures. We will test this coating on cobalt-chromium coupons for wear reduction of UHMWPE mating pieces. Coating uniformity, adhesion, and other relevant physical properties will be determined. Success in Phase I will lead to tests on actual hip components in Phase II.