Comparative evaluation of retreatment techniques by using different file systems from oval-shaped canals

INTRODUCTION: Endodontic failure resolves after complete removal of obturating material followed by disinfection, cleaning, shaping and three-dimensional obturation. MATERIALS AND METHODS: Seventy single-rooted mandibular premolars, with single oval-shaped root canal were included. They were decoronated at a length of 16 mm from the apex. Shaping and cleaning were performed, and obturation was done using the warm lateral compaction technique. The teeth were divided into seven groups according to retreatment procedures (Hand files; ProTaper Universal retreatment files; MTwo(®) Retreatment system; R-Endo(®) Retreatment system; ProTaper Universal retreatment files with solvent and ultrasonics; MTwo(®) R with solvent, and ultrasonics and R-Endo(®) with solvent and ultrasonics). The data were obtained and subjected to the statistical analysis. RESULTS: All instrumentation techniques left obturating material with least in Group 6 and maximum Group 5. The mean time taken for complete retreatment procedure was minimum in Group 2 and maximum with Group 1. CONCLUSION: MTwo(®) R with solvent and ultrasonics, R-Endo(®), and R-Endo(®) with solvent and ultrasonics were effective in gutta-percha removal from coronal third, middle third, and apical third, respectively. Significance: Nonsurgical endodontic retreatment using rotary files helps in gaining access to infected teeth. During retreatment procedure, this helps disinfectant to reach in critical areas of the root canal system, thereby decreasing the microbial load, leading to achieve healthy periradicular tissues.