A Retrospective Study of Roots and Root Canal Morphology in Mandibular Premolars using Cone Beam Computed Tomography in Delhi-NCR

Introduction: The anatomical heterogeneity of mandibular premolars has always been considered an enigma and it makes them potentially prone to high rates of endodontic failure. Only few studies have discussed the potential role of Cone Beam Computed Tomography (CBCT) in the assessment of root morphology, canal configuration and their complex variations. Aim: To investigate the number of roots and root canals along with the canal configuration in mandibular premolars in the Delhi-National Capital Region population using CBCT imaging. Materials and Methods: The retrospective observational study was conducted where 432 CBCT images of 108 patients were acquired from different CBCT centres in Delhi - NCR region to determine the anatomy and morphology of mandibular premolars. The number of roots, root canals and their configuration and its association with symmetry and gender was evaluated. Pearson Chi-square test and Fisher'sexact test were used for statistical analysis. Results: The mandibular first and second premolars reported with single root in 94.9% and 98.1% cases, respectively. Majority of 1st premolars displayed 2 canals (59.7%) whereas 2nd premolars exhibited single canal (58.3%) more frequently. Type I configuration was most prevalent in both 1st premolar (39.8%) and 2nd premolars (60.2%). Type V configuration was significantly reported on the left in both mandibular 1st and 2nd premolars (13.9% and 4.6%), respectively. There was no significant gender predilection observed for the morphology of roots, root canal and canal configuration. Conclusion: In Delhi-NCR, there was a high prevalence of multiple canals and variable configurations in 1st premolars whereas single root canal and Type I canal configuration were more frequent in 2nd premolars with a significant bilateral distribution. However, in both mandibular premolars there was a slight inclination reported for multiple canals and variable configurations towards left with no gender predilection.