## 1 Introduction  
Dental implant therapy has had a high success rate with successful maintenance for many years. Nevertheless, peri-implant inflammation is commonly observed after placing dental implants [1]. Peri-implant diseases have become increasingly relevant with the growing role of implant therapy in modern dentistry. Peri-implant diseases comprise two entities: peri-implant mucositis and peri-implantitis [2]. Peri-implant mucositis describes an inflammatory lesion residing in the soft tissues, while peri-implantitis describes an inflammatory reaction involving both the soft tissues and the supporting bone around the implant [3,4]. A recent systematic review and meta-analysis focused on the prevalence of peri-implant diseases in 47 selected studies with at least a three-year average follow-up period and at least 30 subjects and implants [5]. Therein, [PERSON] et al. reported weighted mean prevalence of implant- and subject-based peri-implantitis and peri-implant mucositis of 9.25%, 19.83%, 29.48% and 46.83%, respectively. Removal of bacterial deposits is essential in the treatment of peri-implant infections. Various therapeutic modalities, including chemical and mechanical disruption of peri-implant biofilm, have been shown to have certain beneficial effects on peri-implant infections [6]. However, biofilm-associated infection may be resistant to antimicrobial therapy without mechanical disruption [6]. The overall resistance of biofilm bacteria may be attributed to protection by extracellular polymeric substances, the adoption of resistant physiological states or phenotypes, or the horizontal transfer of resistance and virulence genes within the biofilm community [7, 8, 9]. Non-surgical mechanical treatment was found to be ineffective for peri-implantitis in various clinical trials and reviews [10, 11, 12]. Hence, surgical and regenerative therapies are preferred for the management of peri-implantitis lesions [13]. Many implant surface decontamination methods using chemical agents, mechanical debridement, or lasers have been proposed. Several methods or agents, including saline, citric acid, chlorhexiidine, air-powder abrasion, hydrogen peroxide, and antimicrobials, have been used for surface decontamination in the surgical management of peri-implantitis lesions, but no agent has been found to be superior [13,14]. The use of mechanical instruments such as metal curettes and ultrasonic scalers on titanium is prohibited as it may cause significant implant surface alterations that may lead to plaque attachment [15,16]. Subsequently, the application of lasers has been considered for decontamination of implant surfaces. The wavelengths of lasers most commonly used in periodontitis, including diode lasers, neodymium-doped yttrium, aluminum and garnet (Nd:YAG) lasers, erbium-doped yttrium, aluminum and garnet (Er:YAG) lasers and CO\({}_{2}\) lasers range from 819 to 10,600 nm. Of the lasers emitting in the near- and mid-infrared spectral range, the Er:YAG laser exhibits high absorption of its emission wavelength (2940 nm) in water and provides the capability to remove calculus effectively without causing thermal side effects to the adjacent tissues [16]. The interaction between laser light and metal surfaces is mainly determined by the degree of absorption and reflection. Each metal features a certain spectral reflection capacity that is dependent upon the specific wavelength of the laser. The reflection capacity of titanium for an Er:YAG laser with a 2940 nm wavelength is 71%, whereas the reflection capacity of titanium for a CO\({}_{2}\) laser at 10,000 nm is 96% [17]. With high reflectivity, the implant surface does not absorb the radiation, and subsequently, there is no temperature increase, which could damage the implant surface. An in vitro study showed a bactericidal effect and no excessive temperature elevation with Er:YAG laser irradiation of different titanium surfaces [18].