ABSTRACT
Background: There are limited clinical experiments addressing the effects of photodynamic therapy (PDT) and low‑level laser therapy (LLLT) as an adjunct to conventional scaling and root planing (SRP) alone. Aim: The aim of this clinical trial was to evaluate the clinical effects of adjunctive use of PDT, combination of PDT with LLLT as adjunct to conventional SRP alone in the treatment of chronic periodontitis. Materials and Methods: In a single‑centered randomized and controlled clinical trial, 24 patients (15 males and 9 females) with untreated chronic periodontitis were randomly assigned in a split‑mouth design into three treatment groups which included Group I: SRP only, Group II: SRP and PDT (1% methylene blue [MB] solution), and Group III: SRP, PDT, and LLLT. Clinical parameters such as plaque index, gingival index, modified sulcular bleeding index, probing depth (PD), and clinical attachment level (CAL) were measured at baseline, 1, 3, and 6 months after therapy. Results: Within each group, significant improvements (P < 0.001) were found for all variables in 6‑month follow‑up compared with baseline. The improvement in clinical parameters was significantly greater in Group III compared to Group I and Group II. The mean PD (mm) reduction from baseline to 6 months in Group I was 2.50 ± 0.54, Group II was 2.57 ± 0.53, and Group III was 3.14 ± 0.50. The mean CAL (mm) gain from baseline to 6 months in Group I was 2.63 ± 0.47, Group II was 2.55 ± 0.44, and Group III was 3.07 ± 0.55. Conclusion: In patients with chronic periodontitis, a combination of a single application of PDT (using a 980 nm laser and MB) and LLLT provide additional benefit to SRP in terms of clinical parameters 6 months following the intervention.