Antibacterial effect of hydrogen peroxide-titanium dioxide suspensions in the decontamination of rough titanium surfaces

<p>The chemical decontamination of infected dental implants is essential for the successful treatment of peri-implantitis. The aim of this study was to assess the antibacterial effect of a hydrogen peroxide-titanium dioxide (H<sub>2</sub>O<sub>2</sub>–TiO<sub>2</sub>) suspension against <i>Staphylococcus epidermidis</i> biofilms. Titanium (Ti) coins were inoculated with a bioluminescent <i>S. epidermidis</i> strain for 8 h and subsequently exposed to H<sub>2</sub>O<sub>2</sub> with and without TiO<sub>2</sub> nanoparticles or chlorhexidine (CHX). Bacterial regrowth, bacterial load and viability after decontamination were analyzed by continuous luminescence monitoring, live/dead staining and scanning electron microscopy. Bacterial regrowth was delayed on surfaces treated with H<sub>2</sub>O<sub>2</sub>–TiO<sub>2</sub> compared to H<sub>2</sub>O<sub>2</sub>. H<sub>2</sub>O<sub>2</sub>-based treatments resulted in a lower bacterial load compared to CHX. Few viable bacteria were found on surfaces treated with H<sub>2</sub>O<sub>2</sub> and H<sub>2</sub>O<sub>2</sub>–TiO<sub>2</sub>, which contrasted with a uniform layer of dead bacteria for surfaces treated with CHX. H<sub>2</sub>O<sub>2</sub>–TiO<sub>2</sub> suspensions could therefore be considered an alternative approach in the decontamination of dental implants.</p>