A cone-beam computed tomography study of the prevalence and location of the second mesiobuccal root canal in maxillary molars

Abstract

Objectives This study aimed to investigate the incidence and location of the second mesiobuccal root (MB2) canal in maxillary molars with the aid of various measuring points and lines using cone-beam computed tomography (CT). Materials and Methods A total of 205 images of patients who underwent cone-beam CT examinations between 2011 and 2015 as part of their dental diagnosis and treatment were included. There were 76 images of the maxillary first molar and 135 images of the maxillary second molar. Canal orifices were detected at −1 mm from the top of the pulpal floor on cone-beam CT images. Image assessment was performed by 2 observers in reformatted image planes using software. Assessments included measurement of the distance between the MB1 and MB2 canals, and the angles between the lines connecting the MB1-MB2 and distobuccal (DB)-palatal (P) canals. The data were analyzed using the student's t -test. Results The prevalence of the MB2 canal was 86.8% in the first molar and 28.9% in the second molar. The angle between the lines connecting the MB1-MB2 and DB-P canals was 2.3° ± 5.7° in the first molar and −3.95° ± 7.73° in the second molar. The distance between the MB1 and MB2 canals was 2.1 ± 0.44 mm in the first molar and 1.98 ± 0.42 mm in the second molar. Conclusions The angles between the lines connecting the MB1-MB2 and DB-P canals was almost parallel. These findings may aid in the prediction of the location of the MB2 canal orifice.

Location angle of second mesio-buccal canal in maxillary molars of an Indian population: an in vivo retrospective CBCT evaluation and proposal of a new classification

“…It was found that the MB2 canal can be located within 5 mm of the MB1 canal ( Sujith et al, 2014 ). The study performed by Lee et al (2020) on 211 teeth showed that the MB1–MB2 canal distance between the orifices of the first molar was 2.53 mm for the adjacent molar, it was 2.42 mm, both in the unknown population. A similar observation was found in a study with 2.67 mm and 2 mm in maxillary first and second molars (1,100 teeth), respectively ( Betancourt et al, 2016 ).…”

“…The CEJ was referenced for restructuring the image to allow simple recognizability with highly reproducible results. Clinicians acknowledge the root canal orifice at the pulpal floor after access cavity preparation, which further increases the ease of locating the canal ( Lee et al, 2020 ; Deutsch et al, 2005 ).…”

“…Sixty-seven maxillary first molars showed positive angle III, and sixty-eight maxillary second molars showed positive angle II. Another study was performed by Lee et al (2020) , in which the angles obtained were 2.30° ± 5.70° in the first molar and −3.95° ± 7.73° in the second. The angles between the connecting imaginary lines were within ±8°.…”

“…The inability of clinicians to recognize the heterogeneity of root canal therapy and to locate every canal in the tooth is one of the main causative factors for the failure of the therapy ( Lee et al, 2020 ). Understanding the anatomy of the tooth structure and the root canal system in depth is essential to the success of the treatment ( Akbarzadeh et al, 2017 ).…”

“…There has been competent literature on the incidence of a second mesiobuccal canal; however, lacunae exist regarding the actual location of this type of canal in any population. Most of the studies concentrate on the incidence of MB2 and/or the MB1–MB2 canal distance ( Lee et al, 2020 ; Akbarzadeh et al, 2017 ; Cotton et al, 2007 ; Tuncer, Haznedaroglu & Sert, 2010 ; Huumonen et al, 2006 ) but rarely measure the angles between the canals, which may help to depict the actual location.…”