Prevalence of C-Shaped Canals in Maxillary and Mandibular Molars: A Retrospective Cone-Beam Computed Tomography study in an Iranian Population

Background: This study evaluated the prevalence of first and second maxillary and mandibular molars with C-shaped canal separately according to gender, type and side of teeth and in terms of C-shaped classification in an Iranian sub-population Methods In this study, 3233 CBCT scans were obtained by Planmeca Scanner device by exposure time = 12 seconds, voxel size = 0.2mm, voltage of 80 kV and 15 mA. The images were observed by visualization software and the incidence of C-shaped canal was classified by Fan et al. (2004) methods. Results In this study the prevalence of C-shaped molars was equal to 4.86%. The incidence of the first and second C-shaped molars was also 2.81% and 5.47%; the incidence of the mandibular first and second C-shaped molars were 4.49% and 8.38%; and this prevalence in maxilla was also 1.47% and 2.32%. Significant differences existed regarding the incidence of C-shaped canal configurations in the first and second molars in total molars (p < 0.001) and mandibular molars (p < 0.004); however, no significant differences were seen regarding C-shaped canal configurations in the first and second maxillary molars .No significant difference was generally observed in the prevalence of C-shaped canals according to side of teeth and between males and females except in the maxilla. Among mandibular molars, C1 and C2 C-shaped configurations were seen more frequently. Conclusion Since the racial factors influence the anatomy of teeth, evaluating the prevalence of C-shaped canals in different populations to identify and raise the level of caution in the treatment of this type of root canals become more and more important.