Evaluation of frequency and anatomy of c-shaped canals along the root canal in mandibular second molars in Tabriz population with CBCT (Cone beam computed tomography)

Abstract

Knowledge of root canal anatomy and variations is essential for successful root canal treatment. The C-shaped root canal system is an anatomical variant of the root canal structure in which a continuous slit or web connects individual root canals to form a letter E?C shape at the root canal orifice. This morphology is most frequently seen in the mandibular second molars but it is also seen in other teeth.the aim of this study was to use Cone-Beam Computed Tomography with 3D images to evaluate the frequency and anatomy of c-shaped canal forms along the root canal in mandibular second molars in an Iranian population (Tabriz). Method and Materials: In this study two Endodontics specialists examined CBCT images of 384 mandibular second molars of Tabriz population to determine the presence of C-shaped canals and their anatomical morphologies. Root canal configurations at three different levels were categorized. Bilateral or unilateral occurrence of C-shaped canals and their relationship with gender, age and tooth location were examined and statistically analyzed using the chi-square test and SPSS 17 software. The significance level was P < 0.05. Results: In this study, 384 mandibular second molars were examined, 82 (21.4%) molars from 58 patients had a C-shaped root canal system. The prevalence of bilateral C-shaped canals was 15.6% among 153 patients with bilateral mandibular second molars.There were no significant differences in the distribution of C-shaped canals with respect to gender and age. Only 4 teeth had the same canal configuration from the orifice to the apical foramen. In the remaining teeth, the cross-sectional canal configuration changed at different levels of the root. Conclusions: According to the findings of this study, there were substantial variations in the number of roots and canal morphology in mandibular second molars. The configuration of C-shaped canals extensively changed along the length of the root and should be considered during preparation and obturation of root canal system.