Evaluation of the local effect of nonsurgical periodontal treatment with and without systemic antibiotic and photodynamic therapy in generalized aggressive periodontitis. A randomized clinical trial

•aPDT as an adjunct to antibiotic treatment in aggressive periodontitis was assessed.•UPD + aPDT exhibited a greater reduction in PD at 3 months when compared to UPD.•aPDT + CLM leads to better clinical advantages when compared to aPDT + UPD.•single aPDT application may not provide benefits to the antibiotic treatment. This study’s aim was to evaluate the local effect of clarithromycin associated with antimicrobial photodynamic therapy (aPDT) in the treatment of generalized aggressive periodontitis. The study sample comprised 72 periodontal pockets on single-rooted teeth in multiple quadrants, with both probing depth and clinical attachment level ≥5 mm, and with bleeding on probing. The pockets were randomly distributed into four groups (n = 18 each) that received ultrasonic periodontal debridement in addition to placebo (the UPD group), systemic clarithromycin (the UPD + CLM group), aPDT (the UPD + aPDT group), or both systemic clarithromycin and aPDT (the UPD + CLM + aPDT group). The measurements were performed prior to treatment (baseline) and at 3 and 6 months postoperatively. The following parameters were evaluated: plaque index, bleeding on probing, probing depth, gingival recession, and clinical attachment level. A 5% significance level was used in the statistical analysis. At 3 months, UPD + aPDT, UPD + CLM, and UPD + CLM + aPDT groups all exhibited reduced probing depths relative to the UPD group (p