Antimicrobial Efficacy of NaOCl and PDT in Primary Root Canal Treatment

This clinical study will compare different root canal disinfection methods used during primary root canal treatment. Root canal infection is mainly caused by bacteria inside the root canal system. Sodium hypochlorite is commonly used as a root canal irrigant because it helps reduce bacteria. Photodynamic therapy is an additional disinfection method that uses a photosensitizing solution and light activation to help kill bacteria. Participants who need primary root canal treatment will be randomly assigned to one of the study groups. The study will compare sodium hypochlorite irrigation alone with sodium hypochlorite supplemented with photodynamic therapy. Additional comparison groups will be used to assess the antimicrobial effect of the disinfection procedures. Bacterial samples will be collected from the root canals before and after the assigned disinfection protocol to measure the reduction in bacterial counts. The main outcome of the study is the reduction in intracanal bacterial load after the disinfection procedure. Postoperative pain will also be assessed using a visual analogue scale at selected time points after treatment. All participants will receive standard root canal treatment, and the final clinical disinfection and treatment procedures will be completed according to accepted endodontic practice.

Inclusion Criteria: * Patients aged 18 to 70, medically healthy or with well-controlled conditions like diabetes or hypertension, needing primary root canal treatment in mature, single-rooted, single-canal teeth were eligible. Teeth required a confirmed pulp necrosis diagnosis, with or without apical periodontitis, and had to be restorable, suitable for single-visit treatment, and amenable to rubber dam isolation. Only cases with dry canals not needing inter-appointment medication were included. All participants provided written informed consent before treatment. Exclusion Criteria: * Patients were excluded if they had uncontrolled systemic disease, immunocompromised status, or any condition affecting infection, healing, or treatment response. Patients who used systemic antibiotics in the previous three months, or took analgesic or anti-inflammatory medication shortly before treatment, were excluded to prevent interference with microbiological or postoperative pain outcomes. Pregnancy, lactation, and known allergy or contraindication to any study material were additional exclusion criteria per institutional requirements. Teeth were excluded if they had irreversible pulpitis, a history of previous or retreatment indication, immature apices, internal or external root resorption, cracks, fractures, perforations, unusual canal anatomy precluding procedural standardisation, advanced periodontal involvement, or unrestorable coronal structure. Canals with persistent exudate, acute swelling, acute abscess, or any condition needing multi-visit treatment were also excluded.