Clinical efficacy of photodynamic therapy as an adjunct to mechanical debridement in the treatment of per-implantitis with abscess

•Clinical, microbial and pain parameters were assessed for PDT and antimicrobial therapy in peri-implantitis with abscess.•PDT helped in reducing bleeding on probing.•PDT has no effect on self-rated pain scores.•PDT is equally effective compared to antimicrobial therapy in reducing peri-implant infections. The aim of the present clinical trial was to evaluate the efficacy of photodynamic therapy (PDT) as an adjunct to mechanical debridement (MD) in the treatment of severe peri-implantitis (PI) with abscess. Selected individuals with severe PI were divided into two groups: Group A: received methylene blue mediated (PDT) using diode laser as an adjunct to MD, whereas, Group B received thrice daily application of 500 mg amoxicillin and 400 mg metronidazole with adjunctive MD. Peri-implant plaque scores (PS), probing depth (PD), bleeding on probing (BOP) and clinical attachment loss (CAL) were reported. Microbial counts of Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were analyzed using polymerase chain reaction. The assessment of pain was done with the help of numeric pain rating scale (NPRS). All assessments were done at baseline and repeated at 6 and 12 months, respectively. A total of 40 individuals completed the clinical trial. Both Group A and Group B comprised of 20 patients respectively. A significant improvement was observed in BOP in Group A at 12 months compared to Group B. No statistically significant changes were seen for NPRS scores between both groups (p > 0.05). Statistically significant differences were observed in values for P. gingivalis, T. denticola and T. forsythia at 6 months follow-up period in comparison to baseline for both Group A and Group B (p < 0.05). Whereas, the values observed at 6 months follow-up period for Porphyromonas gingivalis also reported a statistically significant difference in between the groups (p < 0.05). PDT was equally effective in reducing severe peri-implant symptoms compared to antimicrobial therapy as an adjunct to mechanical debridement.