Rotary file fracture during mesiolingual canal preparation of a lower molar using the bypass technique – Case report

Abstract

This study reported the repair of a periapical lesion after endodontic retreatment. A 42-year-old female patient was referred to an endodontist for endodontic treatment of tooth 47. Clinically, she was asymptomatic, and radiographic examination revealed pulp chamber atresia. Preparation of all root canals was performed with Solla Colors 35.04 rotary instruments at the working length, obtained with an apex locator. At this point, the instrument fractured in the mesiolingual canal, which was bypassed with #08, #10, and #15 C pilot files. Subsequently, ultrasound with a specific endodontic insert TRA11 was selected to remove the fractured file from the mesiolingual canal, without success. Therefore, preparation was performed by bypassing the fractured file with K-Flexofile #20 and #25 manual files. Foraminal patency was achieved with a #15 C pilot file. Subsequently, instrumentation was performed with a Solla S1 file. Root canal obturation was performed using the single cone technique in conjunction with Bio-C Sealer bioceramic endodontic cement. It is concluded that the bypass technique to overcome the fractured instrument is a conservative and effective method.