In vitro and in vivo studies of anti-bacterial copper-bearing titanium alloy for dental application

Abstract

Objective: A novel copper-bearing titanium alloy (Ti-Cu) was fabricated for dental application that is expected to efficiently restrain the growth of bacteria and discourage biofilm formation. The aim of this study was to investigate both the antibacterial activity and biofilm inhibition of Ti-Cu alloy in vitro, and the antibacterial effect of Ti-Cu implant in early stage of peri-implantitis in vivo.

Methods: Staphylococcus aureus and Escherichia coli were selected to evaluate the antibacterial activity of Ti-Cu alloy and Ti served as control. The antibacterial rate, attached bacteria and developed biofilms were studied from quantitative antibacterial test, biofilm observation and bacterial morphological examination. Electrochemical tests were used to investigate the corrosion property of Ti-Cu alloy. Furthermore, both Ti and Ti-Cu dental implants were manufactured and then implanted in the mandibular premolar sites of beagle dogs for 3 months with ligature-infected treatment. Implant-tissue samples were prepared for radiographic analysis, Micro-CT evaluation and histological examination.

Results: Ti-Cu alloy was found to efficiently kill the attached bacteria by ways of damaging cell membranes and cell walls and strongly inhibit the biofilm formation. However, Ti-Cu alloy had excellent corrosion resistance similar with Ti. Further, Ti-Cu dental implants showed superior capacities of inhibiting the bone resorption caused by bacterial infection and enhancing bone formation.

Significance: Ti-Cu alloy strongly inhibited biofilm formation in vitro and prevented bacterial infection associated with dental implant in vivo, making it great potential for application in dental implants with excellent antibacterial viability and positive effect against bone resorption induced by peri-implantitis.

Keywords: Anti-bacterial; Biofilm; Copper; Dental implants; Peri-implantitis; Titanium.