{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T12:16:15Z","timestamp":1790252175039,"version":"4.1.0"},"reference-count":40,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T00:00:00Z","timestamp":1768867200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T00:00:00Z","timestamp":1770940800000},"content-version":"vor","delay-in-days":24,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Oral Health"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>The goal of this study was to compare the filling quality of C-shaped mandibular molars via microcomputed tomography (micro-CT) with that of sealer-based obturation technique (SBO), sealer -based obturation with ultrasonic vibration (SBU) and the continuous wave technique (CWT).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Thirty mandibular molars with C-shaped canals were studied and assigned into three groups according to the filling method used. The CWT group was a continuous wave technique with a resin-based sealer; the SBO group was a sealer-based obturation technique with a calcium silicate sealer; and the SBU (sealer-based ultrasonic vibration) group was subjected to the same method as the SBO group with the addition of ultrasonic vibration. The teeth were scanned via micro-CT 2 times: after preparation and after root canal filling. The total void volume, open porosity and closed porosity were measured. The data were analyzed via ANOVA and Tukey\u2019s test.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Result<\/jats:title>\n                    <jats:p>Compared with the other two groups, the SBU group presented a significantly smaller void volume. In the apical third, the SBU group presented a significantly lower mean percentage of total voids than did the CWT group. In the middle third, the SBU group presented a significantly smaller void volume than the other two groups did, and the percentage volume of voids in the CWT and SBO groups was similar. In the coronal third, no statistically significant differences were observed among the three obturation techniques. In all the obturation techniques, the open porosity was greater than the closed porosity, and the open porosity yielded results similar to those of the total voids.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Sealer-based obturation with ultrasonic vibration resulted in a smaller void volume in mandibular molars with C-shaped canals. The results of this study suggest that sealer-based obturation with ultrasonic vibration can be an effective treatment option for C-shaped root canals.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12903-025-07601-y","type":"journal-article","created":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T05:16:20Z","timestamp":1768886180000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comparison of the obturation quality of C-shaped canals via different filling techniques and ultrasonic vibration"],"prefix":"10.1186","volume":"26","author":[{"given":"Goun","family":"Bae","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Young-Eun","family":"Jang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yemi","family":"Kim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,1,20]]},"reference":[{"issue":"9","key":"7601_CR1","doi-asserted-by":"publisher","first-page":"857","DOI":"10.1111\/j.1365-2591.2011.01896.x","volume":"44","author":"Q Zheng","year":"2011","unstructured":"Zheng Q, Zhang L, Zhou X, Wang Q, Wang Y, Tang L, et al. 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Therefore, it can be an effective option for the treatment of C-shaped canals"],"short-title":[],"issued":{"date-parts":[[2026,1,20]]},"references-count":40,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["7601"],"URL":"https:\/\/doi.org\/10.1186\/s12903-025-07601-y","relation":{},"ISSN":["1472-6831"],"issn-type":[{"value":"1472-6831","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,20]]},"assertion":[{"value":"26 March 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"23 December 2025","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"20 January 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"This study was approved by the local ethics committee of Ewha Womans University (IRB number: EUMC 2023-03-009). The study was performed in accordance with the Declaration of Helsinki. Informed consent was obtained from all participants involved in the study.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"315"}}