Short-term microbiological effects of photodynamic therapy in non-surgical periodontal treatment of residual pockets: A split-mouth RCT

Background and Objective Photodynamic therapy (PDT) has been used as a therapeutic alternative to treat periodontitis, especially in challenging sites that require additional periodontal therapy such as residual pockets. The aim of this split‐mouth randomized trial was to evaluate the microbiological and clinical effects of PDT on non‐surgical treatment of unresponsive pockets. Study Design/Materials and Methods A split‐mouth, randomized controlled clinical trial was conducted in 15 patients presenting at least two residual pockets (probing pocket depth [PPD] ≥5 mm with bleeding on probing [BoP]) in single‐rooted teeth in supportive periodontal therapy. The selected sites randomly received: (1) SRP + PDT: scaling and root planing combined with photodynamic therapy (methylene blue as a photosensitizer), or (2) SRP: scaling and root planing alone. The concentrations of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were evaluated using a Real‐time PCR technique at baseline and 3, 7, 14, and 90 days. Clinical parameters were assessed at baseline and 3 months post‐therapies. Results Both treatments promoted clinical improvements, with additional benefits to the SRP + PDT group in PPD reduction and clinical attachment level gain (P