Prevalence of c-shaped second mandibular molar canals in the population of central Serbia: A cone-beam computed tomography study

Background/Aim. C-shaped canals are complex morphological variation of tooth root canal system that if present could greatly affect the outcome of endodontic therapy. Prevalence of these canal configurations varies between populations of different ethnical and geographical origine. Therefore, the goal of this study was to analyse the prevalence and morphology of second mandibular molar C-shaped canals in the population of Central Serbia. Methods. The study included a total of 199 second mandibular molars receiving cone-beam computed tomography (CBCT) examination and determining the presence of C-shaped canal systems, their configuration, minimal wall thickness and its relative position on axial cross-sections at coronal, middle and apical level. Results. Prevalence of C-shaped second mandibular molars was 5.53%. C1 canal configuration was the most frequent at coronal cross-section, while C2 configuration was the most frequent at middle and apical cross-sections. Minimal wall thickness decreased going apically, with the mean value of 1.01 mm at the coronal, 0.87 mm at the middle, and 0.67 mm at the apical cross-sections. Minimal wall thickness was mostly directed lingually at all cross-sectional levels. Conclusions. C-shaped canals should be expected in second mandibular molars of the population of Central Serbia. CBCT is shown to be the most valuable technique to determine C-shaped canals and facilitate understanding of the C-shaped canal morphology; its implementation could improve the success of endodontic therapy, especially if the complex root canal configuration is present.