Symmetric Three Root Canals in Bilateral Mandibular Premolars Diagnosed by Cone Beam CT: A Case Report

doi:10.13701/j.cnki.kqyxyj.2026.04.014

Abstract

Abstract: This case report describes a rare anatomical variation of symmetrical three root canals in both mandibular first and second premolars, detected via cone-beam computed tomography (CBCT) in a male patient. The incidence of such variations is extremely low, and failure to identify them preoperatively may lead to missed canals and treatment failure. The report highlights the importance of CBCT in diagnosing complex root canal anatomies, as it enables accurate identification of canal features and reduces treatment risks.

Key words: cone-beam computed tomography, mandibular premolars, three root canals, symmetry, case report

CUI Xiaoming, ZHANG Shikuan, HUO Haiyang, ZHANG Zhiyong. Symmetric Three Root Canals in Bilateral Mandibular Premolars Diagnosed by Cone Beam CT: A Case Report[J]. Journal of Oral Science Research, 2026, 42(4): 344-346.

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