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The groups studied were: Group I\u201410 glass fiber posts; Group II\u201410 human dentin posts; Group III\u201410 bovine dentin posts (self-adhesive resin cement); and Group IV\u201410 bovine dentin posts (resin-modified glass-ionomer cements). The coronal part of tooth was restored with a standardized core build-up using composite. All of the groups were submitted to a compression force test and the resistance to fracture was verified using a universal testing machine. The fracture pattern was likewise evaluated.\n<\/jats:p>\n              <\/jats:sec>\n              <jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>The values of resistance to fracture were: 723.3N in group I, 561.5N in group II, 556.6N in group III, and, 613.27N in group IV. However, no statistically significant difference was observed among the groups. The fractures in groups I and II were most commonly found in the middle\/apical third and were considered irreparable. For restored teeth in group III, half of the fractures appeared in the cervical third and were reparable. In group IV, all of the fractures were reparable, with the majority in the cervical thirds.<\/jats:p>\n              <\/jats:sec>\n              <jats:sec>\n                <jats:title>Conclusion<\/jats:title>\n                <jats:p>Bovine dentin can be used as intraradicular post to substitute human dentin and glass fiber posts. The greater the malleability of the post, the greater the chances of survival of the teeth when subjected to fracture testing.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12903-020-01295-0","type":"journal-article","created":{"date-parts":[[2020,11,3]],"date-time":"2020-11-03T12:03:09Z","timestamp":1604404989000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Resistance to fracture of intraradicular posts made of biological materials"],"prefix":"10.1186","volume":"20","author":[{"given":"Karine Ta\u00eds Aguiar","family":"Tavano","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adriana Maria","family":"Botelho","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8628-3122","authenticated-orcid":false,"given":"Dhelfeson Willya","family":"Douglas-de-Oliveira","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio Ferreira","family":"Avila","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rudolf","family":"Huebner","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2020,11,3]]},"reference":[{"key":"1295_CR1","first-page":"369","volume":"17","author":"A Torbj\u00f6rner","year":"2004","unstructured":"Torbj\u00f6rner A, Fransson B. 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