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Published on: May 24, 2022
Endodontic management of a mandibular first molar with four canals in a distal root by using cone-beam computed
Hani Baziar1, Farzaneh Daneshvar1, Abbas Mohammadi2
1Department of Endodontics, Faculty of Dentistry, Zahedan University of Medical Sciences, Zahedan Iran.
Background:
Aberrations in the root canal anatomy are clinically challenging for clinicians. Mandibular first molars usually have 2 roots and 3 or 4 canals, but various combinations may exist. A distal root with three canals is rare and its incidence in literature is about 0.2 - 3%. As a diagnostic tool, cone-beam computed tomography (CBCT) may be a better choice for diagnosis of extra roots or canals comparing to conventional radiography.
Methods:
An endodontic management of a mandibular first molar with six canals was performed. CBCT was used to confirm the diagnosis and to understand the morphology of the canals.
Results:
Evaluation of the axial and coronal slices of CBCT images confirmed the presence of 2 roots and 6 canals. The distal root had four distinct root canal orifices with two apical foramens, being described as type XIV canal configuration.
Conclusions:
Dentists should be aware of unexpected canal morphology when performing endodontic treatment. The present case demonstrated the use of CBCT in diagnosis and negotiation of extra canals in a mandibular first molar.

