Non-Surgical Management of a Mandibular First Molar with Strip Perforation, Separated File, and Canal Ledge: A Case Report.

Root canal mishaps such as perforations, separated instruments, and canal ledges remain significant challenges in endodontic retreatment. This case report describes the successful non-surgical management of a mandibular first molar presenting with a strip perforation in the mesiobuccal canal, a separated file in the mesiolingual canal, and a ledge in the distal canal. The tooth was generally asymptomatic with only mild sensitivity to percussion, without any pockets of endodontic origin. Radiographic examination revealed periapical and furcation radiolucencies. The tooth had a previous endodontic treatment with an infected root canal system and chronic apical periodontitis. Notably, the tooth was left undressed for approximately three months following the initial mishap, negatively influencing prognosis. Nonetheless, considering the patient's preference and the favorable periodontal and restorative conditions, non-surgical retreatment was initiated. Treatment included thorough chemomechanical preparation, bypassing the separated file and ledge, and sealing the perforation with calcium-enriched mixture cement. The tooth was subsequently restored with bonded composite resin. At 12-month follow-up, radiographic signs of healing were evident, and at 18 months, the tooth remained asymptomatic with no clinical or radiographic signs of apical or furcation pathology.