RESUMEN
BACKGROUND: Cone-beam computed tomography (CBCT) could be more beneficial in clinical situations that involve the determination of root canal morphology. AIM: The aim of the study was to ascertain the prevalence of radix molaris (paramolaris-RP and entomolaris-RE) in a subpopulation of Saudi Arabia using CBCT. METHOD: A total of 700 CBCT scans of mandibular permanent first molars were included in this study. All CBCT scans were interpreted by two trained dentists and an endodontist. Mandibular permanent first molars with fully developed roots and closed apices were only included. Computed Tomography scans were obtained from the dental college record. The anatomic characteristics which were checked included: the prevalence of radix molaris in both RE and RP and the prevalence of radix molaris according to the patient's gender and age. All CBCT images were processed and reconstructed using OnDemand3DTM imaging software. RESULTS: Of the 700 patients included, 651 (93.0%) did not have radix molaris, 46 (6.6%) had radix entomolaris and 3 (0.4%) had radix paramolaris in the study group. There was no statistically significant difference between the genders and age in the incidence of RE and RP (P-value < 0.05). CONCLUSION: The study showed that RE prevalence is more compared to RP in the first lower molars in the population studied. It is important to identify extra roots and associated canals to perform successful root canal treatment and avoid failure.