The effectiveness of photodynamic therapy as a complementary therapy to mechanical instrumentation on residual periodontal pocket clinical parameters: A clinical split-mouth test.

The purpose of this study was to evaluate the effectiveness of photodynamic therapy as complementary therapy to mechanical instrumentation on periodontal residual pockets. This longitudinal, prospective, double-blind and controlled split-mouth clinical trial included one hundred and fourteen residual periodontal sites with probing depth ≥ 4 mm and bleeding on probing, which were distributed into two groups: 57 in the test group (SRP + aPDT) - using a low power laser application Therapy XT (DMC Equipamentos Ltda, São Carlos, São Paulo, Brazil) with operational parameters of 660 nm and 110 mW for 15s, and 57 in the control group (SRP). Oral hygiene conditions were evaluated, through the Visible Plaque Index (VPI) and Gingival Bleeding Index (GBI), as well as periodontal clinical outcomes, comprising the Bleeding on Probing (BOP), Probing Depth (PD) and Clinical Attachment Level (CAL) at baseline and after 3 months. Decrease of 17.74% was observed for the VPI after 3 months of follow-up, while the GBI was reduced by 19.91%, thus indicating statistically significant decreases for both parameters (p < 0.001). Decreases in VPI per site, BOP and PD and CAL gain between T0 and T3 in both treatment groups (p < 0.001) were observed, but no statistically significant intergroup differences were found (p > 0.05). Within the parameters used in this study, adjuvant aPDT to SRP did not lead additional benefits regarding the assessed clinical parameters after three months.