Influence of human bone cells on the bio-corrosion of CoCrMo pro thesis

摘要

One of the most common reasons for long-term implant failure, known as osteolysis, can lead to the revision surgery, a risky procedure that should be avoided to the patient. For this purpose, concerns remain with the understanding of interactions between metallic implants and peri-prosthetic biological tissues. Among the aspects affecting biocompatibility are the amounts and forms of corrosion products and their influence on the bone cells response. Indeed orthopedic implants such as ankle articulations are exposed to friction in an aggressive biological environment leading to their degradation and thus an adverse local tissue response. Recent investigations reported that this is mainly due to a complex combination of bone cells activity (osteoblasts) and corrosion products such as wear particles and metal ions. A first set of experiments was focused on the biocompatibility between bone cells and metallic implants without friction force. Both electrochemical techniques and molecular methods were used to determine the corrosion kinetics of the passive film as well as the adhesion and activity of bone cells. A complex "bio-passive" film at the prosthesis surface is expected. But bone cells may to corrode the implant surface by decreasing the pH leading to metal ions release and thus disturbing the secretion of proteins of cells.