**3.5 Laser applications in implant dentistry**

In the previous years the important role of laser in dental implant treatment has been discussed widely [50]. Because of the lack of comparable test and control sites, it is difficult nowadays to know if lasers, with their different types, can be used to treat peri-implantitis using randomized clinical trials [51]. Removal of peri-implant soft tissues and bacterial reduction, uses of laser in second-stage surgery [52], and decontamination of failing implants [53] are the most important applications for lasers in implant dentistry. However there are a lot of limitations of using laser in implant dentistry including the serious alarms about the overheating of the implant and the concern about the melting of the implant surface [54, 55], as well as the fears regarding missing of the re-osseointegration after peri-implantitis treatment with lasers. In recent years a lot of reviews have concentrated on these limitations and gave additional facts about re-stabilization and re-osseointegration of the implants subsequent to the laser decontamination of the implant surface [56]. Deppe et al. [57] showed that CO2 laser decontamination of the surface of implants placed in dogs allowed new bone to grow and be in contact with the implant surface (re-osseointegration). In vitro studies of osteoblasts have confirmed these effects for CO2 and Er,Cr:YSGG lasers [58]. Previous clinical case series were able to demonstrate new bone fill and long-term success of failing implants that were decontaminated with a CO2 laser [59, 60]. The main advantage of using CO2 laser irradiation on implant surfaces is that this wavelength does not pose the risk of overheating [61], unlike other wavelengths, such as that of diode, Nd:YAG, and Er:YAG lasers [62, 63]. A significant increase of the implant surface temperature has been demonstrated when irradiating implant surfaces with a diode laser in vitro for more than 10 s [62–64]. It is possible that authors have presented unsuccessful and nonpredictable clinical results from their studies because of overheating resulting from inconsistent power settings [65]. Limited facts available regarding laserassisted decontamination of implant surfaces, with a limited number of included

studies, as well as the great heterogeneity of the results had been pointed out by a recent systematic review. Nevertheless, even though data is incomplete regarding the clinical use of CO2 (10.6 nm) lasers in the surgical treatment of peri-implantitis, its use appears promising [66].

The following summary of advantages and disadvantages of using lasers for periodontal therapy is based on the literature and the author's experience.
