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Differences by age, sex, left or right side, and bilateral symmetry were also evaluated.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>C-shaped root canals were present in 2.93% MFMs and MSMs (<jats:italic>n<\/jats:italic>\u2009=\u20093035) in the Southwestern Chinese population. A significant higher incidence was observed in the MSMs (5.24%) than in the MFMs (0.54%). Increased incidences were noted in teeth with fused root. Two major types and 5 subtypes of C-shaped canal system of maxillary molars were defined, and the most common type of C-shaped canals is fusion of mesial-buccal (MB) and distal-buccal (DB) canals (Type I subtype C). No significant gender and age differences were noted in the prevalence of C-shaped root canals in this population, and no significant difference was seen in its incidence in the left or right MFMs and MSMs. The bilateral occurrence was observed in 1.27% of the patients.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>C-shaped root canals are more frequently present in MSMs than in MFMs in the Southwestern Chinese population, with Type I subtype C (MB-DB canal fusion) as the most common subtype and low incidence of bilateral symmetry.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12880-022-00831-4","type":"journal-article","created":{"date-parts":[[2022,5,29]],"date-time":"2022-05-29T12:02:48Z","timestamp":1653825768000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Evaluation of C-shaped canals in maxillary molars in a Chinese population using CBCT"],"prefix":"10.1186","volume":"22","author":[{"given":"Yuyan","family":"Qian","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yamei","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jukun","family":"Song","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ping","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhu","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2022,5,29]]},"reference":[{"issue":"1","key":"831_CR1","doi-asserted-by":"publisher","first-page":"3","DOI":"10.1111\/j.1601-1546.2005.00129.x","volume":"10","author":"FJ Vertucci","year":"2010","unstructured":"Vertucci FJ. 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