Electrochemical removal of peri-implantitis associated biofilms from titanium implant surfaces by in-situ anodization

Due to the low efficiency of decontamination, current treatments of peri-implantitis often present limited success in achieving re-osseointegration resulting from bacteria residues on the implant surface. In this work, an elec-trochemical oxidation method was proposed to achieve almost complete plaque removal. For this method, the samples were anodized in electrolyte with fluoride to let the fragile titanium dioxide nanotubes (TNT) form at the biofilm-substrate interface. Then, the samples were abrasive blasted using glycine powder (AA) to completely remove both nanotubes and the biofilms above. The contaminated titanium disks and clinical failed implants were used to evaluate the cleaning potential of conventional air-abrasion (AA) and the TNT + AA method. According to the fluorescence staining results, the TNT + AA method could more thoroughly clean the organic residues including proteins, carbohydrates, and nucleic acids for titanium disks with Porphyromonas gingivalis (P. g.) biofilms. After this treatment, the wettability and the surface roughness of disks were closer to the basic sand-blasting, acid-etched (SLA) surface than the AA method. Moreover, the in vitro response of MG63 cells confirmed that the TNT + AA treated surfaces had better biocompatibility and osteoconductivity than the air-abrasion treated surfaces. On infected implant surfaces, the TNT + AA treatment also yielded a more thorough elimi-nation of contaminants than the AA method. In summary, this new biofilm stripping method has great potential in the clinical treatment of peri-implantitis.