{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T22:02:30Z","timestamp":1770415350280,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T00:00:00Z","timestamp":1770076800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005417","name":"Universiti Teknologi Malaysia","doi-asserted-by":"crossref","award":["Q.J130000.3023.04M13"],"award-info":[{"award-number":["Q.J130000.3023.04M13"]}],"id":[{"id":"10.13039\/501100005417","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomimetics"],"abstract":"<jats:p>Clear aligners are a popular alternative to fixed orthodontic appliances; however, technical data on the optimal final aligner shell thickness for directly printed aligners remain limited. This in vitro experimental pilot study evaluated the mechanical response of patient-specific, directly 3D-printed aligners of four nominal shell thicknesses (0.04, 0.06, 0.08, and 0.10 mm) fabricated from BioMed Clear resin. A single subject with dental crowding was scanned and a set of aligner shells was designed and printed (n = 3 per thickness). Compressive tests up to 1000 N were performed and compressive extension (mm) recorded; group means \u00b1 SD were compared by means of one-way ANOVA. No statistically significant differences in compressive extension were found among the four thickness groups (ANOVA, F(3,8) = 2.242, p = 0.161). The 0.08 mm group showed a lower mean compressive extension in this dataset, but the difference did not reach statistical significance; given the small sample size and single-subject nature of the study, this result should be considered exploratory. This recent study clarifies printing and post-processing parameters and highlights limitations and directions for future work.<\/jats:p>","DOI":"10.3390\/biomimetics11020108","type":"journal-article","created":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T10:03:29Z","timestamp":1770113009000},"page":"108","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["In Vitro Mechanical Study of Three-Dimensional Printed Invisible Dental Aligners for Crowded Dentition Problems: A Patient-Specific Study"],"prefix":"10.3390","volume":"11","author":[{"given":"Zelafy","family":"Reynosa","sequence":"first","affiliation":[{"name":"Bone Biomechanics Laboratory (BBL), Department of Biomedical Engineering and Health Sciences, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hong-Seng","family":"Gan","sequence":"additional","affiliation":[{"name":"School of AI and Advanced Computing, Xi\u2019an Jiaotong\u2014Liverpool University, Suzhou 215000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2705-8379","authenticated-orcid":false,"given":"Muhammad Hanif","family":"Ramlee","sequence":"additional","affiliation":[{"name":"Bone Biomechanics Laboratory (BBL), Department of Biomedical Engineering and Health Sciences, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia"},{"name":"Rehabilitation Nexus (RehabNex) Research Group, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Azaripour, A., Weusmann, J., Mahmoodi, B., Peppas, D., Gerhold-Ay, A., Van Noorden, C.J.F., and Willershausen, B. 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