In vitro Evaluations of Anodic Spark Deposited AZ91 Alloy as Biodegradable Metallic Orthopedic Implant

Surface treatment of Mg alloys is a major approach for its enhanced use as orthopedic implants. In this paper, the in vitro bioactivity, mechanical stability and cytocompatibility of the AZ91 Mg alloy coated by anodic spark deposition (ASD) method are studied. The cytocompatibility behavior is examined by culturing L-929 fibroblast on the surface of the uncoated and ASD-coated AZ91 Mg substrates. The results showed that the corrosion resistance, in vitro bioactivity, mechanical stability and cytocompatibility of biodegradable Mg alloy were improved by ASD coating. Reduction of the degradation rate by ASD coating not only created a relatively stable interface for the cell adhesion and growth, but also arrested the release of corrosion products to reduce the cytotoxicity, hence, resulting in the enhanced cytocompatibility.