Multilayered Adsorption of Commensal Microflora on Implant Surfaces: an Unconventional and Innovative Method to Prevent Bacterial Infections Associated with Biomaterials

Biomaterials may be colonized with infectious biofilms and this frequently leads to progressive loss of tissue. Bacteria encased within biofilms resist antibiotics and the host immune system. With life-threatening complications and the antibiotic resistance crisis, novel therapeutic approaches are essentially required to treat biofilm infections. Commensal microflora-particularly streptococci-modulate the immune system's ability to protect from pathogens. In imitation of this natural phenomenon, the present study describes a novel method of applying the commensal, Streptococcus oralis, as a coating on implants to prevent infectious biofilms. Implants are coated with a simple thermal process to circumvent sepsis persuaded by live microflora and for a stable multilayered coating. Titanium discs coated with S. oralis antagonize the biofilm-making capabilities of single, dual, or multispecies periodontal pathogens: Porphyromonas gingivalis, Treponema denticola, Veillonella dispar, and Actinomyces naeslundii-under both static and flow conditions. The bacterial adhesion force measured with atomic force microscopy (AFM) reduces on coated titanium suggesting that electrostatic interactions are mainly responsible for the decrease in maximum adhesion peak. Importantly, S. oralis coated implants are compatible with human gingival fibroblasts. S. oralis coating may provide a potent novel approach to prevent potentially fatal biofilm infections on biomaterials.