{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,10]],"date-time":"2026-08-10T23:36:06Z","timestamp":1786404966050,"version":"build-2736575974"},"reference-count":40,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2023,1,23]],"date-time":"2023-01-23T00:00:00Z","timestamp":1674432000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013041","name":"Vice-Chancellor for Research, Shiraz University of Medical Sciences","doi-asserted-by":"publisher","award":["00-01-03-24333"],"award-info":[{"award-number":["00-01-03-24333"]}],"id":[{"id":"10.13039\/501100013041","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Objective<\/jats:title>\n<jats:p>This study aimed to investigate the fracture resistance of one-piece screw-retained hybrid monolithic zirconia ceramic restorations in different implant angulations.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Materials and methods<\/jats:title>\n<jats:p>Three implant fixtures were embedded in acrylic resin blocks with 0\u00b0, 15\u00b0, and 25\u00b0 angulations. For each group of implant angulations, 11 screw-retained one-piece monolithic zirconia restorations were made and bonded to the titanium inserts with a dual-cure self-adhesive resin. The complexes were screwed to the implant fixtures with titanium screws. The samples were thermocycled, subjected to compressive load, and fracture modes were recorded. One-way ANOVA and post hoc Tukey\u2019s test were used for statistical analyses (\u03b1 = 0.05).<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>One-way ANOVA showed the fracture resistance to be significanltly different among the study groups (<jats:italic>P<\/jats:italic> = 0.036). The 15\u00b0 group was significantly more resistant than 0\u00b0 (<jats:italic>P<\/jats:italic> = 0.031). However, the 25\u00b0 group was not significantly different from the 15\u00b0 (<jats:italic>P<\/jats:italic> = 0.203) and 0\u00b0 groups (<jats:italic>P<\/jats:italic> = 0.624). Fractures occurred only on the restorations, not at the screw levels.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>Tilting the implant up to 15\u00b0 improves the fracture resistance of one-piece screw-retained hybrid monolithic zirconia restorations; however, increasing the tilt to 25\u00b0 would not yield restorations with significantly better fracture strength than the straight implants. Accordingly, when angulated implants are indicated in the esthetic zones, one-piece screw-retained hybrid monolithic zirconia ceramic restorations can be used with acceptable fracture strength.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0280816","type":"journal-article","created":{"date-parts":[[2023,1,23]],"date-time":"2023-01-23T18:26:56Z","timestamp":1674498416000},"page":"e0280816","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":11,"title":["Implant angulation and fracture resistance of one-piece screw-retained hybrid monolithic zirconia ceramic restorations"],"prefix":"10.1371","volume":"18","author":[{"given":"Milad","family":"Bonyatpour","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1091-9574","authenticated-orcid":true,"given":"Rashin","family":"Giti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Behrad","family":"Erfanian","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2023,1,23]]},"reference":[{"key":"pone.0280816.ref001","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.ijom.2014.10.023","article-title":"Evaluation of survival and success rates of dental implants reported in longitudinal studies with a follow-up period of at least 10 years: a systematic review","volume":"44","author":"V Moraschini","year":"2015","journal-title":"Int J Oral Maxillofac 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