Toluidine Blue-Based Photodynamic Therapy for Antibacterial Activity and Postoperative Pain

This clinical study aims to evaluate the antimicrobial effectiveness and postoperative pain outcomes of photodynamic therapy using Toluidine Blue O as an adjunct to conventional root canal treatment in patients diagnosed with symptomatic irreversible pulpitis. Photodynamic therapy is a non-invasive light-activated disinfection method, and this study will compare its performance with standard endodontic treatment protocols. The results are expected to provide clinical evidence regarding its potential benefits in reducing intracanal bacterial load and improving postoperative patient comfort.

Inclusion Criteria: 1. Patients aged between 18 and 65 years 2. Presence of asymptomatic apical periodontitis with necrotic pulp in single-rooted maxillary or mandibular incisors, canines, or premolars 3. Periapical Index (PAI) score ≥ 2 4. Patients classified as ASA I (American Society of Anesthesiologists Physical Status Classification) 5. Preoperative pain score \< 50 on the Visual Analog Scale (VAS) Exclusion Criteria: 1. Multi-rooted teeth 2. Patients classified as ASA II or higher 3. Pregnant women or those with suspected pregnancy 4. Root canal curvature greater than 25° according to the Schilder method 5. Patients diagnosed with generalized periodontitis 6. Periodontal pocket depth \> 3 mm in the related tooth 7. Use of analgesic medication within the past 72 hours 8. Use of antibiotic therapy within the past month 9. Presence of swelling and positive response to palpation/percussion tests