Novel Tio2 Coatings For Visible Light-Responsive Titanium Implants

Peri-implantitis is a key challenge in implant dentistry. In recent years, TiO2 as a pho-tosensitizer of photodynamic antimicrobial therapy (APDT) is often preferred in the treatment of peri-implantitis. However, due to its wide bandgap, TiO2 exhibits photo-catalytic activity mainly under ultraviolet (UV) light. So developing a antibacterial TiO2 coatings with visible light response on implant surfaces remains a challenge. To address this, we used the micro-arc oxidation (MAO) technique combined with high-temperature annealing to fabricate vanadium (V) and silicon (Si) co-doped TiO2 coatings on titanium surfaces. Comprehensive analyses of the standard optimization parameters, surface morphology, chemical composition, optical properties, biological properties, and antibacterial performance under visible light were conducted. It showed that the co-doped coatings, characterized by a brown-black appearance, absorbed more visible light and maintained excellent biocompatibility. Furthermore, the coatings demonstrated significant antibacterial activity against Staphylococcus au-reus and Escherichia coli under visible light. The study unveiled a preliminary mecha-nism involving impurity energy level transitions and suppression of electron-hole re-combination, which enhanced the visible light response. And the reactive oxygen spe-cies (ROS) produced after the energy level transition make the coating surface have certain antibacterial properties. These findings highlight the potential of this coating technology for modifying the transcutaneous or abutment surfaces of dental implants, thereby reducing the risk of peri-implantitis.