<p>The aim of this study was to analyze the presence of C-shaped canal configurations in mandibular molar teeth of patients who presented to our clinic, using cone-beam computed tomography (CBCT) and three-dimensional (3D) modeling, in relation to the contralateral counterparts in the same jaw and by gender. Additionally, root canal morphologies of mandibular molars were investigated. CBCT images obtained from a total of 504 patients between March 2016- September 2021 were evaluated. The patients included 244 females (48.42%) and 260 males (51.58%) aged between 13 and 79 years (mean age: 36.3). C-shaped canal configurations detected in the CBCT images were further analyzed using 3D modeling techniques. A total of 1495 mandibular molar teeth were examined. After excluding extracted teeth and those not meeting the inclusion criteria, C-shaped canal configurations were identified in 68 teeth (4.54%). According to gender, the incidence was 9.8% in females and 8.1% in males. There was no statistically significant difference in the incidence of C-shaped canals between genders (<i>P = </i>0.53). Among the qualified 61 teeth with C-shaped canals, 46 (75.4%) also showed C-shaped canal morphology in their contralateral counterparts. Of the 45 patients in whom C-shaped canals were identified, 38 had bilateral mandibular second molars, and 23 of these (60.5%) exhibited bilateral C-shaped canal configurations. C-shaped canal configurations can be precisely identified using CBCT and 3D modeling methods. Early detection of such anatomical variations may facilitate clinical procedures and contribute to the success of root canal treatments.</p>