Advanced methods for identification of middle mesial canal in mandibular molars: An in vitro study

Abstract

Introduction: Failures of root canal treatment are mainly due to missed canals and ignorance about the anatomy of the root canal system. The middle mesial (MM) canal is one such type of canal in mandibular molars which is often missed. The aim of this study was to identify MM canals first with unaided eyes, then after troughing, followed by magnification and to compare it with cone beam computed tomography (CBCT). Materials and Methods: Fifty extracted mandibular first and second molars were taken. Preoperative CBCT scans were done for these intact teeth, which were not studied at this stage. Access cavities were made and detection and negotiation of the MM canals was done first with unaided eyes, followed by other added aids like troughing and magnification. Then, CBCT scans were evaluated to compare the incidence obtained and to study the configuration of the found canals. Results: The number of MM canal found with unaided eyes was 29% and 46% in the first and second molars which increased to 41.6% and 50% after troughing the groove between mesiobuccal and mesiolingual canal. It further increased to 45.85% and 53.8% after magnification. CBCT analysis showed same number of canals, but studying the canal configuration, clinically helped in negotiation of five otherwise nonnegotiable canals. Ninety percent of MM canals in the first molars and 100% in the second molars were confluent type, whereas 10% in the first molars were independent type. Conclusion: Troughing, magnification, and CBCT can help us in better identification and negotiation of otherwise difficult to find MM canals.