The Relationship Between Crown Shape and Root Canal Morphology of Maxillary Second Molars in an Iraqi Sub-population Using Cone Beam Computed Tomography (CBCT)


  • Rawa O. Ibrahim Conservative Department, College of Dentistry, University of Sulaimani, Kurdistan Region, Iraq. Author



Crown shape, CBCT, Maxillary second molar, MB2, Root canal configuration


Objective: This study aimed to look into how crown shape affected the architecture of the root canals.

Methods: Nine hundred and fifty-four CBCT scans of maxillary second molars were evaluated. The relation between the crown shape
and sex, root number, and root canals was determined. The frequency of the second canal in the mesiobuccal root (MB2), its age
relation, and the symmetry of the concurrence of anatomical variations in contralateral molars were analyzed. The chi-square test was
used for the analysis of the outcomes. It was deemed significant at P< 0.05.

Results: Overall, rhomboidal-shaped crowns comprised 60.1% of all crowns, while heart-shaped crowns made up 39.9%. Three-rooted
teeth were the most common (74.5%), followed by two-rooted teeth (11.9%) and one-rooted teeth (8.5%), while four-rooted teeth made
up only 5% of all samples. The most prevalent result in terms of the canal number was three canals (67%), followed by four canals
(24.8%), two canals (7.3%), one canal (0.6%), and five canals (0.4%). Males were less likely to have crowns with a heart-shaped
structure than females. The rhomboidal crown (22%) had a higher occurrence of MB2 canals when compared to the heart-shaped crown (2.8%).

Conclusions: Given the constraints of this research, it would seem that the rhomboid form of the upper second molar crown is more
prevalent, with a greater tendency to have three and four roots and the presence of MB2 than the heart-shaped form.


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How to Cite

The Relationship Between Crown Shape and Root Canal Morphology of Maxillary Second Molars in an Iraqi Sub-population Using Cone Beam Computed Tomography (CBCT). (2024). Sulaimani Dental Journal, 11(1), 8.