Remoción de instrumento fracturado en premolar mandibular con anatomía radicular compleja: Reporte de caso

Abstract

The success of endodontic treatment depends on the localization, complete preparation, and disinfection of the root canals, as well as a thorough understanding of the teeth’s internal anatomy. This case report presents the management of a mandibular first premolar with complex root morphology (type 1-2-2 configuration, by tomography), diagnosed with pulp necrosis and chronic apical abscess, in which a file fracture occurred during endodontic treatment. Studies reported that up to 46% of mandibular first premolars may present more than one canal, increasing the risk of complications such as file fracture, particularly in the presence of curvatures or calcifications. In this case, magnification and ultrasonics were used to remove a 3 mm metallic fragment located in the middle third of the mesial canal, thus overcoming a clinically challenging situation. Complete biomechanical preparation and three-dimensional obturation were performed, achieving full clinical resolution of the infection. The 2-year and 4-month follow-up demonstrated apical bone healing and preservation of periodontal structures, supporting the evidence that instrument removal significantly improves prognosis in cases with periapical lesions. It can be concluded that knowledge of dental anatomy, proper case planning, and the use of technology are crucial in the successful removal of a detached instrument.