Root and root canal morphology of permanent mandibular first premolars in a Jordanian subpopulation: A cone-beam computed tomography study

Introduction: Understanding variations in roots and canal morphology using both conventional and modern classification systems is essential for the success of endodontic treatment. This study aimed to assess the root and canal configurations of mandibular first premolars using cone-beam computed tomography (CBCT) in a Jordanian subpopulation. Materials and Methods: A retrospective analysis of three hundred CBCT scans (comprising six hundred teeth) was conducted. The configurations of roots and canals, the presence of C-shaped canals, radicular grooves, and taurodontism, were examined, applying Ahmed’s, and Fan’s classifications. Associations among variables (gender, age) were analyzed using the Pearson’s Chi-square test and statistical significance at P < 0.05. Results: Root morphology: Single-rooted teeth were most common (98.7%), the remaining were double rooted teeth (1.3%). Radicular grooves were identified in 24.3% of the teeth. Root canal morphology: single canal Ahmed’s 1 MP 1 – 1 – 1 configuration was the most frequently observed canal type accounting for 75%, and more prevalent in females (81.75%) than males (69.15%). The prevalence of two canals Ahmed’s 1 MP 1 – 2 – 2 was 10.7% with higher prevalence in males (15.95%) than females (6.3%). C-shaped canals appeared in 11.6% of cases, often associated with mesial radicular grooves (10.1%). Taurodontism was rare (0.83%). Root number, C-shaped canals, radicular grooves, and taurodontism were not related to gender or age. Conclusion: A significant proportion of the subpopulation exhibited complex root canal anatomy, including split and C-shaped canals, highlighting the importance of CBCT imaging for optimizing clinical procedures and improving endodontic outcomes.