Apatite-forming ability of micro-arc plasma oxidized layer of titanium in simulated body fluids

Micro-arc plasma oxidation (MAO) in sulfuric acid was performed to induce apatite-forming ability of the titanium surface. After MAO treatment, the specimens were immersed in a simulated body fluid (SBF) or modified SBFs that had higher pH, calcium and phosphorus concentration than SBF to investigate apatite formation on their surfaces. Immersing in the conventional SBF at 36.5 °C, the specimen showed low ability of apatite formation on the surface, while immersion in the modified SBFs showed higher potential of the apatite formation on the MAO surface than mere Ti surface. This indicates that the MAO treatment leads a potential of bioactivity, i.e. osteoconduction, on titanium substrates.