Impact of Antimicrobial Photodynamic Therapy Combined with Mechanical Debridement on Clinical Parameters and Peri-implant Microbiota in Patients with Peri-implantitis: A Prospective Clinical Study

Introduction: Peri-implantitis is an inflammatory condition affecting tissues around dental implants, often leading to implant failure. Mechanical debridement is the standard non surgical treatment, but adjunctive therapies like antimicrobial Photodynamic Therapy (aPDT) may enhance clinical outcomes and reduce peri-implant pathogens. Aim: To evaluate the adjunctive effect of aPDT combined with mechanical debridement on clinical parameters and peri-implant microbiota in patients with peri-implantitis. Materials and Methods: A prospective clinical study was conducted at the Department of Periodontology, Saveetha Dental College and Hospital, Chennai, Tamil Nadu, India, from November 2024 to March 2025, with 50 peri-implantitis patients aged 25–60 years, randomly allocated to control (Group-1) (mechanical debridement only, n=25) or test (Group-2) (mechanical debridement+aPDT, n=25) groups. Clinical parameters including Plaque Index (PI), Gingival Index (GI), Probing Depth (PD) and Clinical Attachment Level (CAL) were recorded at baseline and three months. Subgingival plaque samples were collected for Tannerella forsythia quantification via Reverse Transcription-Polymerase Chain Reaction (RTPCR). Data were analysed using independent and paired t-tests with significance set at p<0.05. Results: Group-1 (32.56±5.77 years) included 12 males and 13 females, while Group-2 (33.39±4.94 years) comprised 13 males and 12 females. No significant intergroup differences in age or gender were noted (p>0.05). Both groups showed significant improvements from baseline to three months in PI, GI, PD, CAL and T. forsythia levels (p<0.001). The test group demonstrated significantly greater reductions in all parameters compared to controls at three months (p<0.05). Conclusion: aPDT significantly enhances clinical and microbiological outcomes in non surgical peri-implantitis management compared to mechanical debridement alone.