{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T21:19:32Z","timestamp":1785187172975,"version":"3.55.0"},"reference-count":29,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T00:00:00Z","timestamp":1766016000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundac\u0327\u00e3o para a Ci\u00eancia e a Tecnologia","award":["10.54499\/UID\/04044\/2025"],"award-info":[{"award-number":["10.54499\/UID\/04044\/2025"]}]},{"name":"ARISE","award":["10.54499\/LA\/P\/0112\/2020"],"award-info":[{"award-number":["10.54499\/LA\/P\/0112\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFB"],"abstract":"<jats:p>This study aimed to identify the optimal printing orientation (X, Y, or Z axis) and positioning of a mandibular molar presenting an isthmus using PolyJet\u2122 technology. The influence of these parameters on dimensional accuracy and on the behavior of 3D-printed teeth (3DPT) during endodontic preparation with ProTaper Gold\u00ae system was evaluated. Six groups (XA, XB, YA, YB, ZA, ZB; n = 10) were printed with different axis orientations and distinct isthmus positions relative to the build platform. All samples underwent micro-computed tomography scanning before and after endodontic preparation. Regarding preoperative analyses\u2014canal volume, centroids, and total tooth volume and area\u2014no significant differences were found between groups XA\u2013YA or XB\u2013YB (p &gt; 0.05), supporting their comparability. In contrast, groups ZA and ZB differed significantly from all others (p &lt; 0.05), failing to meet equivalence required for further comparison, and were therefore excluded. Postoperative evaluation\u2014volume change, centroid displacement, transportation, and unprepared areas\u2014revealed no significant differences between XA\u2013YA and XB\u2013YB. Within the limitations of this study, both printing orientation and position affected the accuracy and repeatability of 3DPT, with positioning exerting the greatest influence, while their behavior towards endodontic preparation remained consistent across orientations.<\/jats:p>","DOI":"10.3390\/jfb16120471","type":"journal-article","created":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:32:03Z","timestamp":1766068323000},"page":"471","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Does Printing Orientation Matter in PolyJet 3D Printed Teeth for Endodontics? A Micro-CT Analysis"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2191-2338","authenticated-orcid":false,"given":"Cl\u00e1udia","family":"Barbosa","sequence":"first","affiliation":[{"name":"Endodontics and Restorative Dentistry Unit, School of Medicine and Dentistry, University of Santiago de Compostela, 15701 Santiago de Compostela, Spain"},{"name":"FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, 4200-150 Porto, Portugal"},{"name":"RISE-Health, Faculty of Health Sciences, University Fernando Pessoa, Fernando Pessoa Teaching and Culture Foundation, 4200-150 Porto, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4848-744X","authenticated-orcid":false,"given":"Tiago","family":"Reis","sequence":"additional","affiliation":[{"name":"FP-I3ID, FP-BHS, Faculty of Health Sciences, University Fernando Pessoa, 4200-150 Porto, Portugal"},{"name":"CDRSP, Polytechnic University of Leiria, 2430-028 Marinha Grande, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-5965-2137","authenticated-orcid":false,"given":"Jos\u00e9 B.","family":"Reis","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9659-7646","authenticated-orcid":false,"given":"Margarida","family":"Franco","sequence":"additional","affiliation":[{"name":"CDRSP, Polytechnic University of Leiria, 2430-028 Marinha Grande, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4099-8488","authenticated-orcid":false,"given":"Catarina","family":"Batista","sequence":"additional","affiliation":[{"name":"CDRSP, Polytechnic University of Leiria, 2430-028 Marinha Grande, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5407-0579","authenticated-orcid":false,"given":"Rui B.","family":"Ruben","sequence":"additional","affiliation":[{"name":"CDRSP, Polytechnic University of Leiria, 2430-028 Marinha Grande, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4297-4220","authenticated-orcid":false,"given":"Benjam\u00edn","family":"Mart\u00edn-Biedma","sequence":"additional","affiliation":[{"name":"Oral Sciences Research Group, Endodontics and Restorative Dentistry Unit, School of Medicine and Dentistry, University of Santiago de Compostela, Health Research Institute of Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4496-6582","authenticated-orcid":false,"given":"Jose","family":"Mart\u00edn-Cruces","sequence":"additional","affiliation":[{"name":"Endodontics and Restorative Dentistry Unit, School of Medicine and Dentistry, University of Santiago de Compostela, 15701 Santiago de Compostela, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Subbaiah, N.K., Chaudhari, P.K., Duggal, R., and Samrit, V.D. 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Endod."}],"container-title":["Journal of Functional Biomaterials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-4983\/16\/12\/471\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:35:36Z","timestamp":1766068536000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-4983\/16\/12\/471"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12,18]]},"references-count":29,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2025,12]]}},"alternative-id":["jfb16120471"],"URL":"https:\/\/doi.org\/10.3390\/jfb16120471","relation":{},"ISSN":["2079-4983"],"issn-type":[{"value":"2079-4983","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12,18]]}}}