Effects of multiple sessions of antimicrobial photodynamic therapy (aPDT) in the treatment of periodontitis in patients with uncompensated type 2 diabetes: a randomized controlled clinical study

Background: The aim of this study was to compare, through clinical and microbiological analysis, the use of multiple applications of aPDT as an adjuvant therapy to non-surgical periodontal treatment of stage III and IV grade C periodontitis in type 2 diabetic (DM2) patients. Methods: Thirty-four patients with non-compensated DM2 and periodontitis were randomly divided into two groups: SRP Group (n = 17): scaling and root planing (SRP); and SRP+aPDT Group (n = 17): SRP followed by 3 consecutive aPDT applications, immediately, 48 and 96 h after in pockets with probing depth (PD) ≥5 mm. In SRP+aPDT, after 1 min of irrigation with methylene blue (10 mg/ml), the sites were irradiated with a 660 nm diode laser for 50 s (157 J/cm², 4.7 J, 100 mW). Porphyromonas gingivalis (P. gingivalis) and Prevotella intermedia (P. intermedia) were quantified by real-time qPCR. Periodontal clinical and microbiological data (baseline, 90 and 180 days) were statistically analyzed (α = 5%). Results: There was a significant reduction in PD and bleeding on probing at 90 and 180 days post-treatment in both groups (p<0.05). The SRP+aPDT group presented a significant reduction in the number of residual pockets at 90 and 180 days (p<0.05). The SRP+aPDT group presented reduced PD means in deep pockets 180 days post-treatment (p<0.05). No differences were observed in P. gingivalis and P. intermedia levels (p>0.05). Conclusion: The results of present study indicate that the use of multiples aPDT sessions as adjuvant therapy in the periodontal treatment of uncompensated diabetic patients with periodontitis promotes additional clinical benefits.