Role of TiO2 Nanotubes on the Surface of Implants in Osseointegration in Animal Models: A Systematic Review and Meta-Analysis.

Abstract

This systematic review and meta-analysis aims to synthesize evidence relating to the effects of TiO2 nanotubes on osseointegration in animal models. The focused question was "Does the preparation of TiO2 nanotubes on the surface of implants enhance osseointegration?" Searches were performed for relevant manuscripts up to September 2019 using the PubMed, Embase, Scopus and Google Scholar databases with terms such as "TiO2 nanotubes" in combination with "osseointegration", "osteogenic", "osteogenesis", and "bone regeneration". The titles, abstracts and full texts of the manuscripts were reviewed in accordance with the eligibility criteria. The meta-analysis were then performed to analyze the effects of TiO2 nanotubes in bone-implant contact (BIC) and biomechanical tests. Fourteen manuscripts were included for the systematic review and meta-analysis. Eleven studies showed that the results of a histological analysis, micro-CT evaluation and biomechanical tests were significantly higher near TiO2 than titanium. The meta-analysis demonstrating similar results in the BIC and biomechanical tests were obtained. The selected studies also showed the preferable nanotube diameter (70, 80, or 100 nm) to enhance osseointegration in BIC and/or bone area (BA). TiO2 nanotubes, especially those with large diameters, enhanced osseointegration near titanium implants. Compared to bare nanotubes, TiO2 nanotube composite coatings resulted in higher osteogenic ability.