Effect of Surface Treatment on Titanium Surface Free Energy and its Relation to Bacterial Activity: A Systematic Review.

The surface properties of titanium dental implants, such as wettability and surface free energy, influence the adhesion of microorganisms responsible for inflammation and infection of peri-implant tissues. This systematic review aimed to investigate the relationship of titanium surface treatments, surface free energy/wettability property and its relationship with bacterial activity. This systematic review followed PRISMA 2020 (Preferred Reporting Items for Systematic Review and MetaAnalysis) guidelines and was registered in the OpenScience Framework (osf.io/ejnct). PubMed, ScienceDirect, Embase, and Scopus library databases were used from custom search strategies. Inclusion criteria were research articles that studied titanium or its alloys for wetting property and its correlation with adhesion. Of the 697 articles initially identified, 27 were selected after full-text reading and application of the eligibility criteria. In general, the evaluated studies showed that regardless of the surface treatment, there was an increase in titanium hydrophilicity and concomitant reduction in bacterial adhesion. The surface treatment of titanium results in higher surface free energy and lower bacterial adhesion. Hydrophilic titanium surfaces prevent adhesion of hydrophobic bacteria in early stages.