In Vivo Study on the Material Properties of iRoot SP and nRoot SP Root Canal Sealers

Inclusion Criteria: * Age ≥ 18 years. * Diagnosis of apical periodontitis conforming to the diagnostic criteria in Endodontics. * The affected tooth is deemed restorable upon evaluation, with non-vital pulp requiring extirpation. * The affected tooth is a single tooth with a fully developed apical foramen. * No root resorption and no significant morphological variation of the root canal. * The affected tooth is undergoing primary root canal treatment. * Periapical radiolucency with a diameter of 1-5 mm and no peripheral sclerotic border observed on preoperative radiographs. * Patient is in normal mental state, conscious, and capable of normal communication. * Patient has provided informed consent. Exclusion Criteria: * Patients with alveolar bone loss exceeding one-third of the root length. * Affected teeth with root fracture, root canal obstruction, calcification, or root surface caries. * Patients with severe systemic diseases (e.g., osteoporosis, mental disorders, hepatic or renal insufficiency). * Patients who have taken analgesics, immunosuppressants, or antibiotics within one week prior to enrollment. * Patients with concurrent periapical cysts, oral tumors, or other oral diseases. * Pregnant or lactating patients. * Patients with dental phobia, severe gag reflex, limited mouth opening, or poor compliance. * Patients with a known allergy to the root canal sealer materials.