Enhancement of Calcium Phosphate Formation on Zirconium by Combination of Simple Electrochemical Treatments

Electrochemical surface treatments of micro-arc oxidation (MAO) and following cathodic polarization were performed on zirconium (Zr) disks in this study to enhance the bioactivity of Zr. The surface oxide layers formed with electrochemical treatments on Zr disks were characterized using surface analyses; the calcium phosphate formation on the specimens after immersion in Hanks' solution was evaluated. As a result, thick calcium phosphate layers formed on only Zr specimens that underwent both MAO treatment with a mixture of calcium glycerophosphate and magnesium acetate and subsequent cathodic polarization treatment with sodium sulfate solution, while no precipitate was observed without treatment. Thus, this technique was confirmed to be a promising method to improve the bioactivity of Zr.