Peri-implant care with the CO₂ laser: In vitro and in vivo results

Background: Numerous applications for dental lasers have been proposed for both clinical use and experimental purposes. A new indication might be the sterilization of exposed implant surfaces in order to rehabilitate ailing implants. The purposes of this study were to assess CO₂ laser parameters for the decontamination process in vitro and to evaluate the method in vivo. Methods: In vitro, temperature changes at the bone-titanium implant interface were recorded during use of a CO₂ laser-scanning system (Swiftlase®) and the effects of laser irradiation on titanium implants were examined. In vivo, in 6 beagle dogs, a total of 60 implants and bony defects were treated either conventionally by air-powder-abrasive or by laser irradiation or in combination to evaluate if reosseointegration can occur. In 16 patients (41 ailing implants), the reliability of the CO₂ laser-assisted vs. conventional decontamination was tested. Results: Depending on the parameters chosen, melting and other surface alterations could be seen in vitro. In continuous wave mode, mean power output of 2.5 W for a maximum of 10 s is suitable for the decontamination process. In the beagle dog model, histologic examination revealed new direct bone-to-implant contact following laser-assisted therapy. The clinical study showed 4 months after therapy that laser-decontaminated implants and soft tissue resection resulted in statistically significant better radiographic parameters than conventional decontamination plus soft tissue resection. Conclusions: From these results it was concluded that treatment of peri-implantitis can be optimized using CO ₂ laser-assisted implant decontamination. Nevertheless, further studies are required in this field.