Beta-titanium alloys versus surface treatment. How much does it improve their antimicrobial activity? A systematic review

Purpose

Beta titanium (β-Ti) alloys have shown promising outcomes in recent years, but whether they have intrinsic antimicrobial activity is unclear. So the objective was to assess the existing literature and answer “Do surface treatments applied to beta titanium alloys for implants present statistically significant results for antimicrobial activity when compared to the control group?”.

Methods

The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines were followed. The personalized search strategy was applied to Embase, PubMed, Science Direct, and Scopus. Experimental in vitro studies that evaluated the influence of surface treatments on β-Ti alloys to improve antimicrobial activity without the restriction of time and language were included. The risk of bias was assessed by Joanna Briggs Institute (JBI) adapted tool.

Results

690 articles were found, and after the removal of duplicates, 642 remained. Nineteen were selected for full-text reading, and two were selected from their reference lists. Eight of them met the eligibility criteria and were included. Quantitative analysis was not performed due to the heterogeneity of the studies. All studies had a low risk of bias.

Conclusion

All treatments evaluated provided a statistically significant improvement in antimicrobial activity with a significant reduction in bacterial adhesion despite the heterogeneity of the studies. Current literature presents three groups of surface treatment for beta titanium alloys: 1. Implantation of antimicrobial ion, 2. Bioactive polymers with antibiotics, and 3. Non-antimicrobial surface treatments.