Effect of Rotary File Number on MB2 Canal Negotiation and Postoperative Pain

Inclusion Criteria

• •Systemically healthy individuals aged between 20 and 65 years
• •Requiring primary endodontic treatment of maxillary first molars
• •Diagnosis of asymptomatic apical periodontitis and pulp necrosis based on clinical and radiographic findings
• •Presence of a second mesiobuccal (MB2) canal in the maxillary first molar
• •Absence of or only minimal preoperative pain or symptoms
• •Periapical lesions smaller than 5 mm in diameter
• •Ability to comply with follow-up visits and effectively communicate during the treatment process