Bioactivity assessment of titanium sheets electrochemically coated with thick oxide film

Bone formation around a metallic implant is a complex process that involves micro- and nano-metric interactions. In order to obtain faster osseointegration it is necessary to develop adequate surface treatments. Recently, the effect of coatings on implants performance has being studied, specially those related to the titanium oxide. In this work, a thick oxide layer on titanium surface was electrochemically produced and characterized. Incubation of this material into simulated body fluids for 7 days showed that a layer containing calcium (Ca) and phosphorus (P) was precipitated on the titanium surface. By XPS analysis the Ca/P ratio was equal to 1.61 and the calcium and phosphorus binding energies were compatible with hydroxyapatite and phosphate, respectively. Fourier-transformed infrared spectroscopy results indicated the presence of carbonate bands besides phosphate ones. Consequently, we can conclude that the oxide film exhibits suitable in vitro behavior due to its ability of inducing the precipitation of a calcium-phosphate layer similar to the bone-like apatite.