Surface characteristics and bioactivity of an anodized titanium surface

Purpose: The aim of this study was to evaluate the surface properties and biological response of an anodized titanium surface by cell proliferation and alkaline phosphatase activity analysis. Methods: Commercial pure titanium (Ti) disks were prepared. The samples were divided into an untreated machined Ti group and anodized Ti group. The anodization of cp-Ti was formed using a constant voltage of 270 V for 60 seconds. The surface properties were evaluated using scanning electron microscopy, X-ray photoelectron spectroscopy, and an image analyzing microscope. The surface roughness was evaluated by atomic force microscopy and a profilometer. The contact angle and surface energy were analyzed. Cell adhesion, cell proliferation, and alkaline phosphatase activity were evaluated using mouse MC3T3-E1 cells. Results: The anodized Ti group had a more porous and thicker layer on its surface. The surface roughness of the two groups measured by the profilometer showed no significant difference (P>0.001). The anodized Ti dioxide (TiO2) surface exhibited better corrosion resistance and showed a significantly lower contact angle than the machined Ti surface (P>0.001). Although there was no significant difference in the cell viability between the two groups (P>0.001), the anodized TiO2 surface showed significantly enhanced alkaline phosphatase activity (P<0.001). Conclusions: These results suggest that the surface modification of Ti by anodic oxidation improved the osteogenic response of the osteoblast cells.