Introduction of Bioactivity to Plasma Sprayed TiO₂ Coating with Nanostructured Surface by Post-Treatment

In this work, a TiO₂ coating with nanostructured surface was obtained through plasma sprayed nano-sized TiO₂ powder. Its bonding strength onto Ti-6Al-4V substrate is high up to 38 MPa. At same time, we have successfully improved the bioactivity of plasma sprayed TiO₂ coating with nanostructured surface using hydrogen ion implantation and UV illumination. Bone-like apatite can form on the surface of the post-treated TiO₂ coatings after they are soaked in simulated body fluid for a period of time. Introduction of surface bioactivity (bone conductivity) to plasma-sprayed TiO₂ coatings which are generally recognized to have excellent biocompatibility and corrosion resistance as well as high bonding to titanium alloys makes them more superior than many current biomedical coatings such as plasma-sprayed hydroxyapatite.