Marjan Babadi Borujeni, Parisa Ilkhanizadeh, Hiva Ebrahimi,
Volume 39, Issue 0 (3-2026)
Abstract
Background and Aims: Identification of the second mesiobuccal canal (MB2) in maxillary first molars is considered one of the major challenges in endodontic treatment. This study aimed to investigate the prevalence of missed MB2 canals using cone-beam computed tomography (CBCT).
Materials and Methods: This descriptive-analytical retrospective study was conducted on CBCT images taken in years between 2014 and 2018. The images were selected from patients who had undergone treatment on the maxillary first molars and had visited the radiology department of Borujerd dental school. Inclusion criteria were adequate image quality and presence of root canal treatment, while exclusion criteria included incomplete images and teeth lacking complete treatment. Image analysis was performed by an oral radiology specialist. Sample size was calculated using a statistical formula considering confidence level and study power. Data analysis was performed using descriptive statistics and Spearman’s correlation test in SPSS (version 18) at a significance level of P<0.05.
Results: Out of 90 patients examined, 59 cases (65.5%) had an MB2 canal, of which 56 cases (62.2%) had not been identified during initial treatment. The prevalence of MB2 canals was significantly higher in males than in females (P<0.01). No statistically significant association was found between the presence of periapical radiolucency and MB2 canals. In most cases, the MB2 canal orifice appeared as a separate opening.
Conclusion: The results of this study indicated a high prevalence of missed MB2 canals during initial endodontic treatment. The use of CBCT can play an effective role in detecting these canals and improving the success rate of endodontic therapy. Considering individual characteristics such as gender may aid in more accurate diagnosis.
