Ceramic on Metal
Ceramic on metal was introduced in 2000 as it had been noted that bearing surfaces of dissimilar materials were associated with less adhesive wear than 'like on like' couples. Initial clinical studies were performed in South Africa prior to the launch of this bearing surface in Australia in 2008.
Ceramic offers the advantage of being an extremely hard and smooth ‘osteolytic-free’ material, whilst metal as the interactive bearing surface, is another hard surface with self-polishing properties.
Compared with a metal on metal bearing surface, the run-in wear is lower and the steady-state wear is considerably reduced. However, the lowest wear rates occur in ceramic on ceramic. Ceramic on metal has approximately 100 times less wear than a metal on metal pairing. There is a small amount of metal transfer onto the ceramic material. The metal particles from ceramic on metal couples are statistically smaller than metal particles from metal on metal couples.