Micro- and nano-scale adhesion of oral bacteria to biomaterials using atomic force microscopy: A systematic review

To evaluate the available evidence regarding in-vitro studies carried out with atomic force microscopy (AFM) to study the adhesion of oral bacteria under the research question: "Which adhesion parameters have been reported for oral bacteria attachment to surfaces following AFM experiments?" This review was carried out following PRISMA guidelines. The Pubmed, Web of Science and Scopus databases were accessed and original articles reporting in-vitro findings on AFM-based oral bacteria adhesion experiments were included. Study selection and data extraction was performed by two independent researchers. Of the initial 249 screened articles, 24 were included in the final analysis. Overall, the adhesion of oral bacteria to 12 different biomaterial surface types has been explored with AFM including soft materials, dental materials, and other materials. S. mutans was the most frequently studied bacterial species in its early attachment to biomaterials. Regarding AFM-based adhesion parameters, the maximum adhesion force, adhesion energy, rupture and contour lengths, and number of rupture events between oral bacteria and substrates have been quantified and reported. Initial oral bacterial attachment to biomaterials is modulated by a range of cell, environmental, and surface-derived properties. Further research is needed to transfer this knowledge into the clinical setting.