The Elusive Middle Mesial Canal: Clinical Detection and Endodontic Management in Mandibular Molars: A Five-case Series

Abstract

Root canal anatomical variations can complicate endodontic treatment, particularly when additional canals remain undetected. The middle mesial canal (MMC), located between the mesiobuccal and mesiolingual canals of mandibular molars, is clinically important because its omission may permit persistent infection and compromise treatment outcomes. This five-case series describes the detection and management of MMCs in mandibular first and second molars among patients aged 24–39 years who presented with symptomatic irreversible pulpitis, with or without apical periodontitis. Following local anaesthesia, rubber dam isolation, and access preparation, the principal canals were identified and prepared. Additional MMCs were detected through careful pulpal-floor examination using routine clinical findings and armamentarium, including developmental groove inspection, increased inter-orifice distance, radiographic signs, pinpoint bleeding points, a DG-16 explorer, small round burs, and small K-files. The MMCs were negotiated and prepared conservatively with 4% TruNatomy files, followed by obturation using corresponding gutta-percha cones and AH Plus sealer. In all five cases, the canals were described as confluent and were managed without advanced diagnostic aids. The case series highlights the value of systematic exploration of the mesial pulpal floor, particularly in younger patients, and emphasises conservative instrumentation of narrow MMCs to limit unnecessary dentine removal. Careful clinical assessment may assist practitioners in detecting additional anatomy when magnification or three-dimensional imaging is unavailable.