Root and Root Canal Morphology of Premolars in a Sample of the Lebanese Population: Clinical Considerations

Objectives: The aim of this study was to investigate the anatomy of the maxillary and mandibular premolars among a sample of the Lebanese population and to explore their incidence by sex and the symmetry between the left and right sides. Materials and Methods: This retrospective analysis of 250 cone-beam computed tomography (CBCT) scans consisted of 960 maxillary and 972 mandibular premolars. Roots, canals, and morphology types were recorded. Vertucci’s classification was used to categorize the canal morphologies. Fisher’s exact and chi-square tests (P≤.05) were applied. Results: The majority of maxillary first premolars had two roots (85.3%) with two canals (91.3%). Most of the maxillary second premolars showed one root (79.8%). Two-root canals (53.55%) were more common than one canal (44.2%). The three-root, three-canal morphology was rarely spotted in the maxillary first (0.4%) and second premolars (2.3%). The one-root (99.2%) and one-canal (84.5%) morphologies were most frequently located in the mandibular first and second premolars (100%, 88.6%), and two canals being less common (15.5%, 11.4%) correct same as before. The total prevalence of premolars with a complex root canal morphology was 62.4%, found in types II, III, and V to VIII. Men had significantly more roots and root canals in their maxillary first premolars than women (P≤.05). No significant differences were observed between the contralateral premolars (P>.05). Conclusions: Premolars displayed wide variations in root and root canal morphology and symmetry between the contralateral premolars. Keywords: cone-beam computed tomography (CBCT), mandibular premolars, maxillary premolars, root canal anatomy, root canal configuration, sex distribution, symmetry. Objectif Cette étude vise à examiner le nombre de racines, les canaux radiculaires et la morphologie des canaux des prémolaires maxillaires et mandibulaires, au sein d’une population libanaise. Matériels et méthodes 250 images CBCT de 960 prémolaires maxillaires et 972 prémolaires mandibulaires ont été analysées rétrospectivement. Les tests de Fisher Exact et du Chi-Carré (P < 0,05) ont été appliqués pour évaluer le nombre de racines et de canaux radiculaires, la fréquence et la symétrie entre les côtés gauche et droit, ainsi que l’incidence au sein du sexe. La classification de Vertucci a été utilisée pour classer les morphologies des canaux. Résultats Les premières prémolaires maxillaires étaient principalement caractérisées par deux racines (1 racine : 14,4%, 2 racines: 85,3% et 3 racines: 0,4%), avec deux canaux (91,3%). Une racine a été observée dans de nombreuses deuxièmes prémolaires maxillaires (79,8 %). Cependant, deux canaux radiculaires (53,55 %) étaient plus