Electrochemical Disinfection of Dental Implants-A Proof-of-Concept Study

Peri-implantitis has gained significant clinical attention over recent years. This disease is an inflammatory reaction to microorganisms around dental implants. Because of limited accessibility, noninvasive antimicrobial strategies are of high interest. An unexpected approach to implant disinfection may evolve from electrolysis. Given the electric conductivity of titanium implants, alkalinity or active oxidants can be generated in body fluids. The use of dental titanium implants as electrodes for the local generation of disinfectants was investigated. The hypotheses were that electrolysis would reduce viable counts of adhering bacteria and that this reduction would be greater if active oxidative species were generated. As model systems, dental implants, covered with a monospecies biofilm of Escherichia coli C43, were placed in photographic gelatin prepared with physiologic saline. Implants were treated by a continuous current of 0 to 10 mA for 15 minutes. The reduction of viable counts was investigated on cathodes and anodes. In separate experiments, the local change in pH was visualized using color indicators embedded in the gelatin. Oxidative species were detected qualitatively using potassium iodide starch paper. The in situ generated alkaline environment around cathodic implants caused a reduction of up to 2 orders of magnitude in viable E coli counts. On anodic implants, in contrast to their cathodic counterparts, oxidative species were detected. Here, a current of merely 7.5 mA caused complete eradication of the bacteria. This laboratory study shows that electrochemical treatment may provide access to a new way to decontaminate dental implants in situ.