Ozone-gas-mediated surface hydrophilization enhances the cell responses to titanium

Abstract Surface wettability is attracting increasing attention as an important factor that affects the cell/tissue responses of implant materials. Time-dependent hydrocarbon adsorption on the titanium (Ti) implant surface has been reported to decrease the surface hydrophilicity by adsorption of hydrocarbon contaminants from the atmosphere and dramatically decrease the osseointegration over time. In this study, we found that ozone-gas-mediated removal of hydrocarbon contaminants and introduction of –OH groups significantly increased the surface hydrophilicity of acid-etched Ti without changing the original surface topography. Ozone-gas-treated Ti dramatically enhanced osteogenic differentiation of mesenchymal stem cells, as evidenced by greater cell proliferation, alkaline phosphatase activity, and bone-like nodule formation compared with original Ti.