Effects of titanium polishing environments, on bonding behavior of hydroxyapatite ceramics and titanium, by hydrothermal hot-pressing

Ti surfaces were characterized with X-ray photoelectron spectroscopy (XPS) in order to investigate bonding mechanism of Ti and hydroxyapatite (HA) ceramics by hydrothermal hot-pressing (HHP) treatment in 40 MPa pressure, at 150 °C temperature, and for 2 h. Differences in the Ti surfaces properties between water and air in finishing circumstances were revealed from XPS analytic results. Compared with the air finishing Ti samples, the O 1s region XPS spectrums of the water finishing Ti samples was significantly assigned hydroxide or hydroxyl groups (–OH) and hydrate and/or adsorbed water (H2O). The HA/Ti bonding via the HHP processing could be achieved in only water finished Ti samples. It was clarified amount of hydroxide or hydroxyl groups (–OH) remained on titanium surface is important in order to achieve bonding of HA ceramics on Ti by the HHP processing.