MORPHOLOGY AND PREVALENCE OF C-SHAPED CANALS IN MANDIBULAR FIRST MOLARS OF AN IRAQI KURDISTAN REGION POPULATION: A CONE-BEAM COMPUTED TOMOGRAPHY ASSESSMENT.

BACKGROUND

Root canal morphology variations, particularly C-shaped canal configurations, pose substantial challenges to successful endodontic therapy. Accurate preoperative assessment of these complex anatomical patterns remains essential, with cone-beam computed tomography (CBCT) offering superior three-dimensional visualization compared to conventional radiography.

OBJECTIVES

This study aimed to determine the prevalence and morphological characteristics of C-shaped canals and comprehensively evaluate root and canal configurations of mandibular first molars within an Iraqi Kurdish population using CBCT imaging.

METHODS

In this retrospective analysis, CBCT images from 323 patients (186 males, 137 females; aged 18-50 years) originating from Duhok, Erbil, and Suleimani underwent evaluation. Two calibrated endodontists independently examined axial, sagittal, and coronal reconstructions to document root numbers, canal counts, and configurations. Root canal morphology was classified according to Vertucci's system, while Fan et al.'s classification was applied only to confirmed true C-shaped canals. Chi-square analysis assessed gender-based differences, with statistical significance set at p≤0.05.

RESULTS

Two-rooted molars predominated (94.1%), typically exhibiting three (64.4%) or four canals (28.8%). Gender differences proved non-significant for root (p=0.653) and canal numbers (p>0.05). Mesial roots consistently demonstrated Vertucci Type IV morphology (90.1%), while distal roots displayed greater diversity: Type I (58.5%), Type IV (20.1%), and Type II (18.6%). Cross-sectional morphology was not analyzed using Fan classification for non-C-shaped canals. True C-shaped canal configurations were rare (0.6%; 2/323 teeth), with no significant gender association (p>0.05).

CONCLUSION

Iraqi Kurdish mandibular first molars typically exhibit predictable mesial root Type IV anatomy alongside variable distal root morphology requiring careful clinical exploration. The low true C-shaped canal prevalence (0.6%) underscores ethnicity-specific anatomical patterns. These findings advocate judicious CBCT utilization for complex endodontic cases while emphasizing systematic distal canal detection protocols.