Biocompatibility of a titanium–aluminum nitride film coating on a dental alloy

The purpose of this investigation was to develop a coating technique and to study the characteristics of titanium–aluminum nitride [(Ti,Al)N] films deposited on a base-metal alloy (Wiron88®) substrate. Titanium–aluminum nitride thin films were deposited on the alloy surface using a reactive radiofrequency sputtering method. The electrochemical properties of three specimens with and without coating treatment were evaluated. The biocompatibility of the three specimens was tested using a subcutaneous implantation test. Data were analyzed using the t-test with a significance level of p<0.05. Specimens coated with (Ti,Al)N films exhibited significantly improved corrosion resistance (p<0.05). The results from biocompatibility testing, based on tissue reactions at 2 and 12 weeks, revealed substantially enhanced biocompatibility for (Ti,Al)N-coated samples when compared to uncoated samples. This demonstrates that the (Ti,Al)N film can significantly improve electrochemical and biocompatibility properties of the base metal alloy.