Preparation, cell response and apatite-forming ability of microarc oxidized coatings containing Si, Ca and Na on titanium

The formation, cell response and apatite-forming ability of novel TiO ₂-based coatings containing Si, Ca and Na (SCN) on titanium formed by microarc oxidation (MAO) were investigated. The oxidation time has obvious effect on the surface morphology and SCN elements concentrations of the MAO coatings. The current results indicated that the MAO coatings containing SCN possess good apatite-forming ability, which is highly dependent on the applied voltage. And high applied voltage could facilitate for improving the apatite-forming ability of the MAO coatings due to the introduction of a large quantity of SCN elements. It was firstly observed that the induced biomimetic apatite could grow into the pores of MAO coatings, which could facilitate for the fixation of apatite layer. The A-type slightly substituted carbonated-HA and B-type slightly substituted carbonated-HA with HPO₄^2- group were obtained after immersion of the MAO coatings in a simulated body fluid. As expected, the MAO coatings show good biocompatibility according to the cells proliferation.