In Vitro Assessment of a Novel Piranha-Passivated Dental Implant Surface Against Oral Biofilm Formation

Peri-implantitis, a significant complication resulting from bacterial colonization on dental implants, presents a challenge in oral healthcare. Developing surfaces that inhibit bacterial adhesion while promoting tissue integration is crucial for improving implant outcomes. This study aims to evaluate bacterial colonization on a novel passivated surface for dental implants using an in vitro multispecies biofilm model.

Three types of titanium implants (standard, citric acid-passivated, and piranha-passivated) were characterized by analyzing roughness, contact angle values, and surface energy after the passivation treatments. The capacity for biofilm formation on these implants was evaluated using quantitative polymerase chain reaction (qPCR), scanning electron microscopy (SEM), and confocal laser scanning microscopy (CLSM). Bacterial colonization and viability were assessed at 6, 12, and 24 h. In addition, the protein adsorption capacity of these surfaces was determined.

Treatments increased hydrophilicity and polar surface energy, with no change in roughness. Although no statistically significant differences were found, a slightly lower concentration of primary and intermediate colonizers was observed on piranha-treated surfaces compared to citric acid implants, particularly during the 24-h incubation period. CLSM analyses revealed a higher percentage of dead bacteria on piranha-passivated implants over time. Piranha passivation also resulted in the lowest fibrinogen adsorption.

These findings suggest that piranha passivation may be a promising treatment for dental implant surfaces, potentially reducing the risk of peri-implantitis. However, the inherent limitations of the in vitro approach necessitate further clinical trials to validate the efficacy of this surface modification in real-world clinical settings.