**Abstract**

Every year, with the increasing number of dental implants placed, there is an increase in the incidence of peri-implantitis. The treatment of peri-implantitis is very complex and among other things includes mechanical and chemical decontamination of the implant surfaces, which is very challenging and often not predictable due to the surface properties of the implants. Photodynamic therapy recently has emerged as a potential treatment alternative or adjuvant treatment to peri-implantitis. Its potential to decontaminate implant surfaces without damaging the surface and the implants surrounding tissues has generated much interest in the scientific community. The possibilities of photodynamic therapy in treatment of peri-implantitis are opening new challenges in establishing optimal conditions for the clinical application of aPDT. Due to its non-invasiveness and ease of use this method can be effective when applied alone or as an adjunct therapy to conventional methods for treating peri-implantitis.

**Keywords:** photodynamic therapy, implants, peri-implanitits, titanium, zirconia
