Document Type: Original Article


1 Dept. Endodontic, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.

2 Student Research Committee, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.

3 Dept. of Endodontics, Faculty of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.

4 Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.



Statement of the Problem: Considering the vastness of our country, there is a need to study the number of roots and morphology of the maxillary premolar canals teeth in the south of the country. The knowledge of root morphology com influence the outcome of root canal therapy. The aim of this study is to evaluate of number and morphology of maxillary second premolars in south Iranian population. 
Purpose: The aim of this study was to investigate the morphology of maxillary premolar canals in Iranian population by analyzing cone-beam computed tomography scans.
Materials and Method: This cross-sectional retrospective study consisted of CBCT (cone-beam computed tomography) of 280 patients over 16 years of age. Maxillary premolars’ position, number of roots, and root morphology were inspected. The root canal configurations of maxillary premolar teeth were also analyzed according to the Vertucci classification. Chi-square test was performed among canal configurations, tooth position and gender. Significance level was set at P⩽0.05.
Results: In the present study, of 462 maxillary first premolars, 8 (1.73%) teeth had three roots, 222 (48.05%) teeth had two roots, and 232 (50.22%) were single-rooted. In the second maxillary premolar group, of 400 premolars, 2 (0.5%) teeth had three roots, 34 (8.5%) teeth were two-rooted, and 364 (91%) were single-rooted. The most root canal configurations were type IV (71.64%) and type I (63%) in maxillary first and second premolars, respectively. Among females, single rooted premolars were the most prevalent (56.83%), and among males, two-rooted premolars were the most prevalent (57.61%).
Conclusion: This study can provide guidance to the root canals of maxillary premolar teeth for Iranian subpopulation leading to more optimal diagnosis and treatment planning for the endodontists. According to the findings, the complexity of root canal system and the number of roots were less observed in females compared to males.