Evaluation of the radiographic visibility and continuity of the secondary mesiobuccal canal (MB2) in maxillary first molars using cone-beam computed tomography
DOI:
https://doi.org/10.37636/recit.v9n4e487Keywords:
Endodontics, Maxillary first molar, MB2, Root anatomy, Cone-beam computed tomographyAbstract
The identification of the second mesiobuccal canal (MB2) in maxillary first molars represents a diagnostic challenge due to its high anatomical variability and the limitations of traditional two-dimensional imaging. Cone-beam computed tomography (CBCT) offers a three-dimensional evaluation of the root canal system; however, continuous visualization of the MB2 along the root is not always possible. The objective of this study was to evaluate the radiographic visibility and continuity of the MB2 in maxillary first molars using CBCT analysis. A descriptive, observational study was conducted with 35 maxillary first molars obtained from 33 patients without prior endodontic treatment. The analysis consisted of axial slices supported by three-dimensional reconstructions, utilizing the primary mesiobuccal canal (MB1) as a reference. MB2 visibility was classified into complete continuity, partial continuity, and non-identifiable, according to its presence at the cervical, middle, and apical levels. Regarding radiographic continuity, a critical degradation of visibility was observed in a corono-apical direction: the MB2 was visible in 85.7% of the cases in the cervical third, decreasing drastically to 31.4% in the apical third. Statistical analysis using Fisher's exact test determined that the presence of this anatomical variant showed no statistically significant differences regarding sex or side of the arch. This methodology contributes to a more precise interpretation of root anatomy through CBCT, highlighting the potential and limitations of this technology in the terminal portion of the root.
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