Root Canal Morphology Evaluation of Central and Lateral Mandibular Incisors Using Cone-beam Computed Tomography in an Israeli Population

Introduction: Central and lateral mandibular incisors usually have 1 root canal. The purpose of this study was to investigate the prevalence of additional root canals in central and lateral mandibular incisors and to investigate the prevalence of oval and long oval canals in the cervical, middle, and apical thirds of cases with 1 root canal. Methods: A total of 1016 Israeli patients' cone-beam computed tomography scans were screened and evaluated. A total of 1472 central mandibular incisors and 1508 lateral mandibular incisors were examined. The root canal morphology and cross-sectional shape were recorded and analyzed. Results: The overall prevalence of more than 1 root canal in mandibular central and mandibular lateral respectively was 40.5% and 37.9%. The bilateral incidence of more than 1 root canal in mandibular central and mandibular lateral respectively was 69.8% and 68.7%. The root canal separation in type II to type V central and lateral mandibular incisors was found in the middle third of the root in 81.5% and 79.0%, respectively. The septum was smaller than 1 mm in 37% of central mandibular incisors and one-third of lateral mandibular incisors. In central and lateral incisors with 1 root canal, long oval canals were found in the middle third of the root of central and lateral mandibular incisors in 36.8% and 48.9%, respectively. Conclusion: The occurrence of more than 1 root canal in central and lateral mandibular incisors is approximately 40% (type III was the predominant canal type). In central and lateral incisors with 1 root canal, long oval canals are common.