Light-induced bone cement-philic titanium surface

The survival of cemented endosseous implants can be improved by enhancing the bond between the implant and the cement. We hypothesized that the lightinducible generation of super-hydrophilicity of titanium positively affects its bone cement-philicity and bone cement–titanium bonding. Commercially pure titanium disks with machined surface and acid-etched micro roughened surfaces were prepared. Ultra-violet (UV) light treatment (0.1 mW/cm2 UVA and 0.03 mW/cm2 UVB for 48 h) created a super-hydrophilic surface for both surface types. The area of poly-methyl methacrylate (PMMA)- based bone cement spread increased by 30% and 20% on the light-treated machined titanium and acid-etched titanium surfaces, respectively, compared to the matched untreated ones. The contact angle of the bone cement decreased significantly after the light treatment, confirming the enhanced wettability of bone cement by the light treatment. Interfacial tensile stress between the bone cement material and titanium was increased 100% for the machined surface and 50% for the acid-etched surface by light treatment. Interfacial shear stress measured by a pushout test of titanium rods also revealed a 40% increase for the machined surface and 25% increase for the acid-etched surface. In conclusion, the pre-UV light treatment of titanium enhances the wettability and bonding strength of poly-methyl-methacrylate-based bone cement.