Understanding the role of corrosion in the degradation of metal-on-metal implants.

In metal-on-metal joints the primary concerns in terms of long-term durability relate to corrosion, wear, and their joint (tribocorrosion) effects. The release of ions through corrosion processes and nanoscale debris from wear processes can seriously affect joint integrity and can lead to an adverse biological reaction by the host. In this paper an integrated study of corrosion-wear interactions in serum, Dulbecco's Modified Eagle's Medium and 0.3 per cent NaCl has demonstrated that the biological nature of the fluid affects the total degradation rate and also the level of wear-corrosion interactions. The specific action of proteins in corrosion and tribocorrosion for high-carbon Co-Cr-Mo and low-carbon Co-Cr-Mo alloys is discussed.