A mandibular molar with four independent mesial roots: a case report

Aim: The most common anatomical configuration of the mandibular molar is to present two roots and three or four canals, but it’s possible to find many different configurations. A case of unusual mandibular molar is presented to illustrate the anatomic root canal variation.

Summary: Endodontic treatment was performed in a mandibular third molar with five roots, four in the mesial portion and one in the distal portion. The x-ray examination showed an abnormal root canal anatomy, suggesting the presence of extra mesial roots. Cone-beam computed tomography (CBCT) imaging revealed five roots and five root canals, with four independent roots in the mesial portion and one in the distal portion, indicating a rare anatomic configuration. This case report presents the importance of searching for extra canals and the unusual canal morphology, because the knowledge of the most common anatomic characteristics and their possible variations is fundamental to the endodontic treatment success.

Key learning points: (A) The major cause of failure in root canal therapy is the inability to localize and treat all of the canals of the root canal system. (B) Mandibular molars may have complex canal systems and variations. (C) The operating microscope and CBCT interpretation are fundamental in confirming and preventing mistakes about the configuration of root canals.