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Background and Aim: Evaluation of root and canal morphology and anatomy of the teeth is essential for successful root treatment. This study aimed to evaluate the morphology and anatomy of the root canal of maxillary second premolars using the cone-beam computed tomography (CBCT) technique in a radiology center.
Material and Methods: We used CBCT images of a specialized radiology center archived in 2014 in Qazvin and evaluated them by use of Remexis software. Evaluation of the images was carried out by a radiologist and an endodontist. The number of roots and their morphology, number of canals, the direction of root curvature, and canals in buccolingual and mesiodistal directions were assessed using the chi-square test in two genders. The significance level was considered 5%.
Results: A total number of 106 CBCT involving 117-second premolar teeth were evaluated. 93.2 % of the teeth had one root and 6.8 % had two roots. There was no significant difference in the number of roots between the two sexes   (Pv=0.164). According to Vertucci classification for single-rooted teeth, 59.6 % were of type I, 20.2 % of type II, 9.2 % of type III, 0.9 % of type IV, 6.4 % of type V, 1.8 % of type VI, and 1.8 % of type VII. Among two rooted second premolar teeth, 87.5 % were of type I and 12.5 % of type III.
Conclusion: In maxillary second premolars, the majority of teeth had one root with type I and type II canals. During root treatment, these anatomical variations should be considered