Root and Canal Morphology of Mandibular Second Molars in an Egyptian population: A Cone-beam Computed Tomography Study

Abstract Background: This study was uses CBCT to examine the anatomical variations in mandibular second molars in an Egyptian subpopulation. Methods: 350 CBCT images (215 females and 135 males, aged 15–65 years) of mandibular second molars were evaluated. Samples were evaluated in terms of: number of roots, number of root canals, roots’ cross section as well as prevalence and configurations of C-shaped canals. Statistical analysis was done to highlight differences between different categories and their prevalence among genders (significance level was set at p < 0.05). Results: Of the 350 mandibular second molars evaluated, 87.2% were non-C-shaped while 12.8% were C-shaped with no gender-based statistically significant differences (χ2=0.19, p=0.656). Most samples had three root canals (80%) followed by two (16%), then one (3.2%), and finally four (0.8%) root canals. Among the non-C-shaped molars, presence of two roots was most common (83.4%) followed by presence of a single root (16.2%), and only one sample (0.2%) had three roots, and this had no correlation with gender (χ2=1.86, p=0.431). In the mesial roots Type IV Vertucci was the most common configuration found (68.8%), while Type I was the most prevalent in the distal roots (91.8%). The long oval configuration was the most commonly found cross section in mesial roots while “oval” was the most prevalent in distal roots. Conclusion: Egyptian population shows highly variable morphological features in mandibular second molars, hence, CBCT is highly recommended on case-to-case conditions. Keywords : C-shaped canal - Cone beam computed tomography - Mandibular second molar