Journal of Materials Science, Vol.44, No.20, 5544-5551, 2009
Mechanical characterization of anti-infectious, anti-allergic, and bioactive coatings on orthopedic implant surfaces
In total joint replacement much effort has been made to reduce implant loosening. We investigated different implant coatings (copper integrated titanium dioxide (TiO2-Cu), titanium nitride (TiN), plasma polymerized allylamine (PPAAm), and calcium phosphate (CaP)) regarding the adhesion strength and wear resistance. Standardized scratch and adhesive tests were applied. Abrasive wear was measured with artificial bone and bone cement using a special testing machine. All tested coatings have higher bonding strengths than the 22 N/mm(2) required for medical implant surface coatings by ASTM standard 4711-F. Using bone cement, wear testing revealed higher wear rates in most cases. Polished surfaces reduce the amount of wear, whereas rough surfaces highly increase the wear rate due to three-body wear, especially ceramic surfaces. In general, the application of bone cement in conjunction with modified implant surfaces can lead to an increase in wear rate.