Evaluation of Root and Canal Morphology of Maxillary First and Second Molars by Cone Beam Computed Tomography in a Northern Iranian Population

A thorough understanding of tooth and root canal morphology is required for successful root canal treatment. The current study aimed to assess the canal and root morphology of maxillary first molars (MFMs) and maxillary second molars (MSMs) using cone-beam computed tomography (CBCT).  

In this cross-sectional study, CBCT scans of 400 patients were used. The number of roots and canals, as well as the morphology of the root canal system of MFMs and MSMs were assessed according to the Vertucci’s classification, separately sorted by gender and by using OnDemand3D dental software. To compare the variables, the Chi-square test was used with a significance level of 0.05.

All the MFMs and MSMs had three roots. The most common morphologies according to the Vertucci’s classification in mesiobuccal (MB) roots of MFMs were type II (43.1%), followed by types I (28.7%), and IV (19.8%); while, types I (63.5%) and II (18.7%) were more commonly found in the MB roots of MSMs. All distobuccal (DB) and palatal roots were type I. The frequency of the second mesiobuccal (MB2) canal in MFMs and MSMs was 71.3% and 36.6%, respectively. Gender had no significant correlation with presence of MB2 canal (P>0.05).

Three roots with four canals were the most common in MFMs while three roots with three canals were the most frequent in MSMs. Variations in MB roots were greater than in other roots. The frequency of MB2 in MFMs was greater than that in MSMs.