Measuring Adhesion Strength of an Improved Dental Biofilm Model on a Titanium Surface

Adhesion of bacteria to oral implant surfaces can lead to oral infections, and the prevention of strong biofilm adherence to implant surfaces can assist in the prevention of these infections like peri-implantitis. In prior studies, single species biofilm adhesion has been quantitatively measured via the laser spallation technique. However, colonizing oral biofilms rarely consists of a single bacteria species. Multiple early colonizer species, including several strains of Streptococci, dominate initial oral biofilm formation. This study aims to characterize the adhesion of a multi-species oral biofilm consisting of S. oralis, S. sanguinis, and S. gordonii on titanium, a common implant material, using the laser spallation technique. Previous work has established these specific Streptococci strains as a multi-species periodontal biofilm model. This study is the first to provide a quantitative adhesion measurement of this multi-species model onto a dental implant surface. First, adhesion strength of the multi-species model is compared to adhesion strength of the single-species streptococci constituents. Fluorescent staining and imaging by fluorescent microscopy are used to identify individual bacteria species within the biofilm. The multi-species biofilm presented in this study provides a more representative model of in vivo early biofilms and provides a more accurate metric for understanding biocompatibility on implant surfaces.