Endodontic Management of a Mandibular First Premolar With Unusual Root and Canal Anatomy: A Case Report

Mandibular first premolars are generally considered to possess a single root and single root canal. However, a considerable amount of anatomical variation has been documented including canal bifurcation and multiple apical foramina. Recognition of these variations are essential to ensure there is no inadequate endodontic treatment or to avoid any missed anatomy. This report describes the endodontic management of mandibular first molar (34) demonstrating an unusual combination of bifurcating root canal system and bulbous enlargement of the root consistent radiographically with hypercementosis. Pre-operative periapical radiography demonstrated an unusually enlarged and bulbous root contour, while careful assessment of the canal trajectory suggested anatomical deviation from the expected single-canal configuration. During endodontic treatment, two distinct canal pathways were identified and negotiated. Working-length radiographs confirmed the presence of separate canal paths within the enlarged root. The case highlights the diagnostic difficulties associated with complex canal anatomy and excessive cemental deposition and emphasises the importance of careful pre-operative radiographic interpretation, angled radiographs, magnification and three-dimensional imaging when indicated. Although additional canals in mandibular first premolars are not uncommon, the coexistence of a bifurcating canal system with marked bulbous root morphology presents an additional anatomical challenge for endodontic management.