Calcium phosphates formation on CaTiO3 coated titanium.

In this study, performance of calcium phosphate formation of CaTiO3 coating film on Ti in Hanks' balanced saline solution (HBSS) was investigated. CaTiO3 thin films with a thickness of 50 nm were deposited on Ti using radiofrequency (RF) magnetron sputtering. The temperature of Ti substrate was adjusted to room temperature (RT) and 873 K. Thereafter, the specimens deposited at RT were annealed at 873 K in air for 7.2 ks. The films were characterized by grazing incident angle X-ray diffractometry (GI-XRD) and X-ray photoelectron spectroscopy (XPS). After immersion in HBSS for 60 d, on CaTiO3 coated Ti, the formation of hydroxyapatite (HAP) was observed. Furthermore, HAP layer formed was thicker on the specimen on which CaTiO3 film was deposited at RT and annealed than that prepared at 873 K. The major difference between both specimens was the chemical properties of the outermost surface. In summary, CaTiO3 thin film deposited at RT and followed by annealing at 873 K for 7.2 ks in air enhances calcium phosphate formation ability on Ti.