Prevalence of C‐shaped canals and three‐rooted mandibular molars in the Iranian population by using cone‐beam computed tomography

OBJECTIVES: This study aimed to evaluate the prevalence of C‐shaped canals and three‐rooted mandibular molars in the Iranian population using cone‐beam computed tomography (CBCT). MATERIALS AND METHODS: This study evaluated mandibular teeth on 292 CBCT scans of patients referred to the Department of Radiology, Faculty of Dentistry, Islamic Azad University, Isfahan, Iran. All CBCT scans were obtained with the same three‐dimensional CBCT scanner, and sections were reconstructed in all three planes (sagittal, axial, and coronal) with 1 mm slice thickness. A total of 291,402, and 200 first, second, and third molars, respectively, were evaluated. Data were analyzed using SPSS software (version 26.0). RESULTS: Of 291 mandibular first molars, 0.7% were single‐rooted, 96.6% were two‐rooted, and 2.7% were three‐rooted. The prevalence of C‐shaped canals was 1.7% in mandibular first molars. Of 402 mandibular second molars, 8.5% were single‐rooted, 90.5% were two‐rooted, and 1% were three‐rooted. The prevalence of C‐shaped canals was 2% in mandibular second molars. Of 200 mandibular third molars, 21.5% were single‐rooted, 77.5% were two‐rooted, and 1% were three‐rooted. The prevalence of C‐shaped canals was 2% in mandibular third molars. CONCLUSION: In the present study, the majority of mandibular molars were two‐rooted, and three‐rooted mandibular molars were less common. The third and second mandibular molars both had an increased prevalence of C‐shaped canals. Mandibular first molars had the highest prevalence of three‐rooted molars.