Adjunctive effect of antimicrobial photodynamic therapy to nonsurgical periodontal treatment in smokers: a randomized clinical trial

The aim of this study was to investigate the adjunctive effect of antimicrobial photodynamic therapy (aPDT) to scaling and root planing (SRP) in smokers with chronic periodontitis. Twenty subjects had two contralateral teeth randomly assigned to receive SRP (SRP group) or SRP + a single episode of aPDT (SRP + aPDT group), with a diode laser and a phenothiazine photosensitizer. Plaque index, bleeding on probing, probing depth (PD), clinical attachment level (CAL), and gingival recession were recorded, and gingival crevicular fluid was collected for assay of IL-1 beta and matrix metalloproteinase (MMP)-8 levels. There was a significant PD reduction (SRP 1.81 +/- 0.52 mm/SRP + aPDT 1.58 +/- 1.28 mm; p < 0.001) and a significant CAL gain (SRP 1.60 +/- 0.92 mm/SRP + aPDT 1.41 +/- 1.58 mm; p < 0.001) for both groups. Significant differences were not observed in between-group comparisons. IL-1 beta level in gingival crevicular fluid was higher in SRP group after 1 week (SRP 24.65 +/- 18.85 pg/mu L/SRP + aPDT 34.07 +/- 24.81 pg/mu L; p = 0.048), and MMP-8 level was higher in SRP group after 12 weeks (SRP 303.31 +/- 331.62 pg/mu L/SRP + aPDT 534.23 +/- 647.37 pg/mu L; p = 0.024). There were no statistically significant differences in intragroup comparisons. The adjunctive effect of aPDT did not warrant improvements on clinical parameters in smokers. However, it resulted in a suppression of IL-1 beta and MMP-8 when compared with SRP alone.