Comparison of Laser-Assisted and Conventional Non-Surgical Treatments for Improving Gum and Implant Health in Patients with Peri-Implantitis

Before the intervention, all clinical and microbiological measurements were performed by a blinded and calibrated periodontist to establish baseline values. Arm 1 (Mechanical debridement + active Er,Cr:YSGG laser): Participants in this group then underwent the same mechanical debridement protocol as the control group using titanium curettes (Langer 1/2, 8 mm). Immediately after debridement, Er,Cr:YSGG laser irradiation (WaterLase iPlus™, Biolase Inc., Irvine, CA, USA) was applied to the peri-implant pocket. Laser parameters were set at a wavelength of 2780 nm, H mode (short pulse), power 1.5 W, frequency 30 Hz, pulse duration 140 µs, and 50% water and 40% air settings, using an RPFT5 fiber tip (14 mm, 1 mm spot size). The laser was applied in a bottom-up technique, starting from the base of the peri-implant pocket and moving coronally in parallel to the implant surface for approximately 30 seconds per site. The fiber tip was held at a 1 mm distance from the implant surface in non-contact mode. Patients were recalled on day 7 and day 14 for identical repeated applications. No antibiotics, antiseptic agents, or local anesthesia were used. The duration of each intervention session is approximately 30 minutes per participant, including pre-treatment hypersensitivity assessment (VAS and Schiff scores), tooth isolation and preparation, laser application according to the allocated power setting, and immediate post-treatment evaluation. Adherence to the intervention protocol will be monitored using a standardized operator checklist completed at each session (including laser parameters, treated tooth/teeth, number and duration of passes, and safety measures). All treatments will be performed by the same calibrated periodontist. In addition, laser log data (power setting, frequency, and application time) will be reviewed and noted periodically to confirm that the pre-specified parameters have been followed. After the treatment sessions, participants will be re-evaluated at the 3-month follow-up visit, during which clinical and microbiological measurements will be repeated by a blinded periodontist who also performed the baseline assessments. The clinical treatments, including mechanical debridement and laser applications, will be carried out by a different clinician who will remain unaware of the study hypotheses and be blinded to the group allocation. Laser parameters will be pre-set and calibrated by an independent researcher not involved in treatment or data evaluation. All procedures will take place at the Department of Periodontology, Faculty of Dentistry, Trakya University (Edirne, Türkiye). Both the treating clinician and participants will wear protective eyewear during laser procedures to ensure safety.