Evaluation of Morphology of Maxillary Premolar Roots and Canals Using Cone-Beam Computed Tomography in Northeastern Iran

Background: Understanding the morphology of the root canal is crucial for successful root canal treatment (CBCT), which is the most effective method for detecting canal anatomy and morphology. This study aimed to investigate the root canal morphology of maxillary premolars using CBCT. Methods: Overall, 71 CBCT images, comprising 97 maxillary first and 94 maxillary second premolars, were analyzed in the current study. Various sections of the CBCT images were examined to gather information on the roots, canals per root, and canal types, categorized using Vertucci’s classification. Statistical analysis was conducted using independent t-tests and Mann-Whitney tests (P<0.05). Results: The first premolars with a single canal had a frequency of 51.5%, while those with two canals had a frequency of 87.6%. For the second premolars, the occurrence of a single canal was over 85%, and for two canals, it was 69.1%. In maxillary first and second premolars, the predominant canal type was type I as per Vertucci’s classification. In terms of root and canal symmetry, about 83.7% and 91.89% of the first premolars exhibited symmetry, with 93.1% and 72.41% of second premolars displaying comparable levels of symmetry. Conclusion: The findings indicated that single-rooted second and double-rooted first premolars were more common in the studied Iranian population. However, the occurrence of three-rooted maxillary first premolars is very low. In terms of Vertucci’s classification, the prevailing canal types were type III, I, and IV in maxillary first premolars and type III, I, and II in maxillary second premolars.