{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T12:30:01Z","timestamp":1788525001391,"version":"build-2803163510"},"reference-count":38,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2024,5,21]],"date-time":"2024-05-21T00:00:00Z","timestamp":1716249600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2024,5,21]],"date-time":"2024-05-21T00:00:00Z","timestamp":1716249600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100009827","name":"Alexandria University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100009827","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Oral Health"],"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Background<\/jats:title>\n                <jats:p>Cement spacer is essential for compensating deformation of zirconia restoration after sintering shrinkage, allowing proper seating and better fracture resistance of the restoration. Studies assessing the effect of cement spacer on fit accuracy and fracture strength of zirconia frameworks are missing in the literature. Therefore, the aim of this study was to evaluate the effect of different cement spacer settings on fit accuracy and fracture strength of 3-unit and 4-unit zirconia frameworks.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Methods<\/jats:title>\n                <jats:p>Sixty standardized stainless-steel master dies were manufactured with 2 prepared abutments for fabricating 3-unit and 4-unit zirconia frameworks. The frameworks were assigned into 6 groups (<jats:italic>n<\/jats:italic>\u2009=\u200910) according to cement spacer setting (30\u00a0\u03bcm, 50\u00a0\u03bcm, and 80\u00a0\u03bcm) as follows: 3-unit frameworks; 3u-30, 3u-50, 3u-80, and 4-unit frameworks; 4u-30, 4u-50, and 4u-80. The frameworks were assessed for fit accuracy with the replica method. The specimens were cemented to their corresponding dies, and the fracture strength was measured in a universal testing machine. The Weibull parameters were calculated for the study groups and fractured specimens were inspected for failure mode. Two-Way ANOVA followed by Tukey test for pairwise comparison between study groups (\u03b1\u2009=\u20090.05).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>The cement spacer had a significant effect on both fit accuracy and fracture strength for 3-unit and 4-unit frameworks. The 50\u00a0\u03bcm spacer had significantly better fit accuracy followed by 80\u00a0\u03bcm, and 30\u00a0\u03bcm spacers. Both 50\u00a0\u03bcm and 80\u00a0\u03bcm spacers had similar fracture strength, and both had significantly better strength than 30\u00a0\u03bcm spacer.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>For both 3-unit and 4-unit zirconia frameworks, 50\u00a0\u03bcm cement spacer can be recommended over 30\u00a0\u03bcm and 80\u00a0\u03bcm spacers for significantly better fit accuracy and adequate fracture strength.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12903-024-04341-3","type":"journal-article","created":{"date-parts":[[2024,5,21]],"date-time":"2024-05-21T08:01:31Z","timestamp":1716278491000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Effect of cement spacer on fit accuracy and fracture strength of 3-unit and 4-unit zirconia frameworks"],"prefix":"10.1186","volume":"24","author":[{"given":"Noha","family":"Morsy","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mona Mohamed","family":"Ghoneim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yomna","family":"Ibrahim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2024,5,21]]},"reference":[{"key":"4341_CR1","doi-asserted-by":"publisher","first-page":"236","DOI":"10.1016\/j.jpor.2013.09.001","volume":"57","author":"T Miyazaki","year":"2013","unstructured":"Miyazaki T, Nakamura T, Matsumura H, Ban S, Kobayashi T. 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