Türk popülasyonunda mandibular molar dişlerde mid mesial kanal görülme sıklığı ve morfolojilerinin KIBT ile retrospektif değerlendirilmesi

Aim: All root canals should be identified, shaped, and filled for complete sealing to perform a successful endodontic treatment. Necrotic tissue residues left in overlooked canals may cause endodontic treatment failure. The morphology of root canal systems may differ based on race. Although teeth generally have common features, morphological differences may be observed among ethnic groups. This study aims to evaluate the prevalence of middle mesial canals in the Turkish population which are observed as a third canal in the mesial root that cannot be identified in every mandibular molar tooth. Material and Method: Cone-beam computed tomography images obtained from patients who applied to the Faculty of Dentistry, Dicle University, between 2015 and 2020 due to various reasons were used in the study. A total of 637 CBCT images that met inclusion criteria were included in the study, and 2177 mandibular molar teeth were examined. 10% of the examined CBCT images were randomly selected and re-evaluated by a single observer every three weeks. Data regarding age and gender were recorded for all images examined. The study population were divided into four groups based on age: ≤20 years old, 21 to 40 years old, 41 to 60 years old, and> 60 years old. Molar teeth were grouped as first, second and third molars and evaluated regarding number of total root, number of total root canal, presence of gastric mesial canal and isthmus, morphology of the middle mesial canal, and the canal criteria where it converged in the presence of a merging type stomach canal and compared with each other. The relationship between age and gender and the incidence of the middle mesial canal in each molar group was examined. The data obtained were analyzed using the SPSS version 21.0 software (IBM). The Chi-Square test was employed to analyze the relationship between groups of nominal variables. A p level of 0.05 was considered significant and it was stated that there was a significant relationship if p level was <0.05. Kappa coefficient was used to evaluate intraobserver agreement level. Results: A total of 90.72% of all mandibular molar teeth examined in the study were double-rooted and 68.72% were triple-rooted. The incidence rate of the mesial canal in the mesial roots of all mandibular molars was 8.36% and it was 15.58%, 5.32%, and 1.09% in the first, second, and third molars, respectively. There is no statistically significant relationship between age and gender and the presence of the middle mesial canal in mandibular molar teeth (p > 0.05). Conclusions: The possibility of the middle mesial canal in the mesial roots should be considered for all mandibular molars. In the mandibular molar teeth, the first molar teeth are the most likely to have the middle mesial canal, and the third molars are the least likely to have it. There is no relationship between gender and age factors and the incidence of the middle mesial canal.