Correlation of root canal morphology of endodontically treated premolar and molar teeth with procedural errors using cone-beam computed tomography in an Iranian population

Introduction
The prevalence of different root canal morphologies and types of endodontic procedural errors has been previously evaluated.

Objectives
This study aimed to assess the quality of endodontic treatments and most common procedural errors as well as to evaluate the correlation of procedural errors with the root canal morphology of premolar and molar teeth according to Vertucci’s classification using cone-beam computed tomography (CBCT).

Material and methods
In this cross-sectional study, 230 endodontically treated teeth were evaluated on 287 CBCT of patients presenting Hamadan Dental School from 2019 to 2021. Canal type was determined according to Vertucci’s classification system. Endodontic procedural errors, including under-filling, over-filling, non- homogenous filling, perforation, and missed canals were also assessed. Correlation between the type of procedural error and root canal morphology was analyzed with chi-square test using SPSS version 23, at 5% level of significance.

Results
Under-filling was the most common procedural error in Vertucci’s type I canals (27.69%, p = 0.92). In types II and IV canals, the most common procedural error was missed canals, with a prevalence rate of 18.36% and 13.63%, respectively. Non-homogenous filling (p = 0.68) and missed canals (p = 0.003) were the most common errors in type III canals (25%). Over-filling (p = 0.05) and non-homogenous (p = 0.68) filling were the most frequent errors in type V canals (28.58%).

Conclusions
Over-filling and missed canals showed a significant correlation with canal type. Moreover, the type of canal demonstrated a significant correlation with the presence of periapical lesions, i.e., periapical lesions showed the highest prevalence in canal types III and V.