Analysis of root number and canal morphology of maxillary premolars using cone-beam computed tomography

This study aimed to evaluate the number of roots and type of root canals in maxillary first and second premolars within a selected Korean population utilizing cone-beam computed tomography (CBCT). Additionally, it sought to investigate potential differences in these features according to sex and tooth type.

CBCT images of 585 maxillary first premolars and 578 maxillary second premolars from 303 patients were retrospectively reviewed. The number of roots was classified based on root morphology, and canal configurations were categorized into 8 types according to the Vertucci classification. For statistical analysis, chi-square or Fisher exact tests were employed to compare root number and canal morphology according to sex and tooth type.

CBCT analysis revealed that 71.5% of maxillary first premolars and 97.6% of maxillary second premolars had 1 root. The most common canal configuration in maxillary first premolars was Vertucci type IV (42.6%), whereas type I predominated in maxillary second premolars (76.5%). Significant differences in root number and canal configurations were found between men and women (P<0.05), with single roots and Vertucci type I canals more commonly observed in women.

Both maxillary first premolars and maxillary second premolars typically had 1 root, with a smaller percentage possessing 2 roots. Significant sex differences were observed in root number and canal type. This study highlights the variability in root number and canal configuration, emphasizing the importance of recognizing these variations to achieve successful endodontic treatment.