The Role of Cone-Beam Computed Tomography in The Prediction of Endodontic Treatment Complications in The Mandibular molars : A Cross-Sectional Study in a Sample of Egyptian Population

This study aimed to predict the difficulty in endodontic treatment of mandibular first and second molars in an Egyptian population sample using CBCT, based on the proximity of molar roots to IAC and their root morphology. Materials and Methods:In this observational study, 106 molars from 40 CBCT scans were retrospectively analyzed using Planmeca Romexis® Viewer. Root apex-to-IAC distances were measured in corrected coronal sections. The number and degree of canal curvatures were assessed in coronal and sagittal views using Schneider’s method via the software's angle tool. Continuous variables were presented as mean, SD, median, and IQR; categorical data as frequencies and percentages. Differences and associations were tested using chi-square and pairwise z-tests. A linear mixed model with Kenward–Roger F-test and Holm’s adjustment assessed associations between root type and IAC distance. Reliability was evaluated using ICC and Cohen’s kappa. Statistical significance was set at p ≤ 0.05. Analyses were conducted using R software. Results:Root-to-IAC distances were significantly greater in first molars than second molars (p < 0.001). Most canals showed multiple moderate-to-severe curvatures in coronal and sagittal cuts except distal canals in which single curves were dominant in sagittal cuts. Inter- and intra-observer reliability was strong (k > 0.8, p < 0.001). Conclusion: In a sample of the Egyptian population, the roots of the mandibular second molar are anatomically positioned closer to IAC compared to those of the mandibular first molar. Most canals of mandibular molars exhibited complex morphology.