Antibacterial and osteogenic stem cell differentiation properties of photoinduced TiO2 nanoparticle-decorated TiO2 nanotubes

Aim: To improve the antibacterial and mammalian cell compatibility properties of titania nanotubes (TNTs) anodized into titanium (Ti). Materials & methods: 3–8-nm TiO2 nanoparticles were decorated on the surface and inside TNT (TNT-TiO2) through a hydrothermal method. After UV light treatment, two types of oral bacteria and stem cells were cultured on the samples to determine antibacterial and compatibility properties. Results: TiO2 nanoparticles increased the surface area and photocatalysis of TNTs. Based on the photocatalysis effect and prolonged photo-induced wettability, the numbers of Streptococcus mutans and Porphyromonas gingivalis were lower on the surface of TNT-TiO2 than pure Ti and TNTs after the first 7 days. Specifically, for S. mutans, the glycosytransferase (gtf) genes were downregulated 0.1–0.2-fold on TNT-TiO2. Due to the different topography and high surface energy of TNT-TiO2, stem cells also showed improved osteogenic functions on TNT-TiO2. Conclusion: In this study, we demonstrated fo...