**9.6 Laser therapy**

Laser treatment using CO2, diode-, Er:YAG- (erbium-doped: yttriumaluminum-garnet), and Er, Cr: YSGG- (erbium, chromium-doped:

yttrium-scandium-gallium-garnet) lasers are used in the treatment of peri-implant diseases [81, 82]. The use of Er:YAG lasers showed significantly better results than mechanical methods in terms of bleeding at peri-implantitis [83]. Er:YAG and Er, Cr: YAG with a wavelength of 3 microns can reduce biofilms up to 90%, but in contrast to most mechanical therapies, any biological compatibilities and cell stimulatory properties cannot be re-induced [84]. The CO2 excimer laser was effective in reducing the anaerobic bacteria [85].
