Assessment of Root Canal Anatomy of Mandibular Permanent Incisors in a Sample of Yemeni Population.

To investigate the root and canal morphology of mandibular using cone-beam computed tomography (CBCT) in a sample of Yemeni population. A total of 320 (160 females and 160 males) Yemeni patient's CBCT scans were examined. A total of 1280 mandibular incisors (640 mandibular central incisors and 640 lateral mandibular incisors) were evaluated. The following items were recorded: (1) number of roots, (2) number of canals, (3) root canal type, and (4) bilateral symmetry in terms of root canal number and root canal type. The effect of gender bilateral symmetry on the incidence of root canal morphology was also investigated. All mandibular central incisors examined in this study had one root. On the other hand, 99.7% of lateral mandibular incisors were single-rooted only 0.3% had two roots. The overall prevalence of second root canals in mandibular central and mandibular lateral was 48.9% and 37.9%, respectively. Where males 28.4% and 27.3% had more canals than females 20.3% and 17.8% in both mandibular central and lateral incisors, respectively. Type I canal configuration was the most prevalent in both mandibular incisors, followed by Type III in central and lateral incisors 38.9% and 34.2%, respectively. The prevalence of the other configuration types was as follows: Type II occurred in 7.5% of central and 7.03% of lateral incisors and Type V occurred in 0.8% of central and 1.1% of lateral incisors. Types IV, V, VI, VII, 1-2-3, 1-2-1-3, and 2-1-2-1 were also found in both mandibular incisors with relatively less frequency, and Type VIII was not detected at all. The bilateral symmetry in the number of root canal was 99.3% in mandibular central incisors and 99.6% in mandibular lateral incisors. Furthermore, 97.18% of the mandibular central incisors and 93.75% of mandibular lateral incisors had symmetry in terms of Vertucci's canal configuration. With no significant difference between gender. Mandibular incisors in the Yemeni population are mainly single rooted with 0.3% having two roots. The occurrence of the second canal in central and lateral mandibular incisors is approximately 46.9% (Type I was the predominant followed by Type III). When at least one tooth had two root canals, bilateral symmetry between contralateral teeth was found in 99.3% and 99.6% of cases for central incisors and lateral incisors, respectively. Males have more incidence of second canals than females.