Enhancement of the bioactivity of titanium oxide nanotubes by precalcification

Titania nanotubes have been thought to be a novel material for improving bioactivity of titanium. In this work, the effect of precalcification (Pre-Ca) on the bioactivity of the TiO2 nanotubes was investigated, which was applied by soaking the TiO2 nanotubes in Na2HPO4 Solution overnight and then in saturated Ca(OH)(2) Solution for 5 h. It was observed that, only after 7 days immersion in a supersaturated calcium phosphate solution (SCP), hydroxyapatite (HA) was formed apparently on the surface of the precalcified TiO2 nanotube specimens. But no obvious HA was observed on the non-precalcified specimens even up to 14 days immersion in the SCP. The bioactivity of titania nanotubes was enhanced by the precalcification procedure. Therefore, it is much easier and faster for the Ca-P coating fabrication on titanium implants with cooperation of the anodic oxidation and precalcification procedure than that with only an anodic oxidation. (c) 2008 Elsevier B.V. All fights reserved.