Prevalence and C-shaped root canal configuration in lower molars in the metropolitan region, Chile.


Objetive: The aim of this study was to determine the prevalence, demographics, and root configuration of C-shaped canals of mandibular molars by means of cone beam computed tomography in the population of the Metropolitan Region, Chile.
Material and Methods: 912 molars (456 first and 456 second molars) resulting from the analysis of 228 mandibular CT scans were evaluated. The root configuration was established by means of a panoramic reconstruction and axial tomographic sections, classifying the presence and type of canals through the analysis of five sections or cuts along the root. Data were statistically analyzed using a 5% confidence interval.
Results: Of the 912 molars analyzed, 70 were classified as C-shaped canals (7.68%), corresponding to 58.33% of those molars that presented fused roots. 95.7% of this root canal configuration was observed in lower second molars, occurring more frequently in females (n=45, 64.29%). 45.65% of the cases that presented C-shaped canals were bilateral and the most frequent configuration was C3 (n=401, 66.63%) according to the Melton classification.
Conclusion: The C-shaped canals of the mandibular molars in the studied population were observed mainly in second molars, showing a clear prevalence among females and a high percentage of bilaterality. The presence of fused roots significantly increases the possibility of finding this type of root configuration.


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How to Cite
PEÑA-BENGOA, Fernando; CONTRERAS-SAN MARTÍN, Juan; MELÉNDEZ-ROJAS, Patricio. Prevalence and C-shaped root canal configuration in lower molars in the metropolitan region, Chile.. Journal of Oral Research, [S.l.], v. 11, n. 4, p. 1-10, aug. 2022. ISSN 0719-2479. Available at: <>. Date accessed: 12 july 2024. doi: