Antimicrobial and Osteogenic Performance Comparison of Titanium Implants between the Conventional Array Structure Surface and Post-etched Surface

Abstract

Ti implants are often unsatisfactory in clinical use due to bacterial infections and difficulty in generating osteogenic activity. Constructing silver-loaded antibacterial coatings is a feasible surface modification strategy for Ti implants. However, achieving the osteogenic performance of the coating while accurately regulating the release of silver ions remains a huge challenge. Here, we combined hydrothermal chemical method and laser etching technology to prepare two completely different surface structures of silver-loaded titanium dioxide coatings on the surface of titanium implants: arrays and different periodic etching structures. The results indicated that it is difficult to achieve a balance between effective antibacterial and cytotoxicity for conventional array structure silver-loaded coatings. The better the antibacterial effect, the greater the cytotoxicity. Compared with the conventional surface, the cytotoxicity and osteogenic activity of post-laser-etched samples can be significantly improved through modulating surface etching intervals, while maintaining excellent antibacterial effects unchanged. The smaller spacing of the periodic array structure leads to a smoother release rate of silver ions and a higher cell survival rate. This study provides a new and simple approach to promote the research of silver-loaded coatings on medical titanium surfaces with dual and osteogenic and antibacterial properties.