{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T18:10:28Z","timestamp":1791655828015,"version":"4.3.4"},"reference-count":23,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T00:00:00Z","timestamp":1663632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"name":"Swiss Society of Aligner Orthodontics"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2023,5,31]]},"abstract":"<jats:title>Summary<\/jats:title>\n               <jats:sec>\n                  <jats:title>Aim<\/jats:title>\n                  <jats:p>To quantitatively assess the degree of conversion and the water-leaching targeted compound from 3D-printed aligners.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Materials and methods<\/jats:title>\n                  <jats:p>3D-printed aligners were made of photopolymerized resin (Tera Harz TC85A). The molecular structure and degree of conversion of the set resin were investigated by ATR-FTIR spectroscopy (n = 5). The aligners (n = 10) were immersed in double distilled water for 1 week at 37\u00b0C and the eluents were analysed using liquid chromatography\/mass spectrometry methods (LC\u2013ESI-MS\/MS for urethane dimethacrylate [UDMA] and LC\u2013APCI-MS\/MS for bispenol-A [BPA]).<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>The resin was composed of aliphatic vinyl ester-urethane monomers, with acrylate and\/or methacrylate functionalization. The degree of conversion was estimated as to 83%. There was no detection of BPA in any of the assessed samples (0.25 \u00b5g\/l). Quantifiable amounts of UDMA were detected in all the exposed samples, ranging from 29 to 96 \u00b5g\/l.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>Although efficiently polymerized and BPA free, the great variability in the amount of UDMA monomer leached from the examined samples may raise concerns on potential health hazards after repeated intraoral exposure, which is indicated for this class of materials.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/ejo\/cjac056","type":"journal-article","created":{"date-parts":[[2022,8,24]],"date-time":"2022-08-24T09:16:54Z","timestamp":1661332614000},"page":"244-249","source":"Crossref","is-referenced-by-count":66,"title":["Leaching from a 3D-printed aligner resin"],"prefix":"10.1093","volume":"45","author":[{"given":"Andreas","family":"Willi","sequence":"first","affiliation":[{"name":"Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich , Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3906-9083","authenticated-orcid":false,"given":"Raphael","family":"Patcas","sequence":"additional","affiliation":[{"name":"Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich , Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sevasti-Kiriaki","family":"Zervou","sequence":"additional","affiliation":[{"name":"Photo-Catalytic Processes and Environmental Chemistry, Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research Demokritos , Athens , Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nearchos","family":"Panayi","sequence":"additional","affiliation":[{"name":"Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich , Switzerland"},{"name":"Department of Dentistry, European University Cyrpus , Nicosia , Cyprus"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc","family":"Sch\u00e4tzle","sequence":"additional","affiliation":[{"name":"Clinic of Orthodontics and Pediatric Dentistry, Center of Dental Medicine, University of Zurich , Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"George","family":"Eliades","sequence":"additional","affiliation":[{"name":"Photo-Catalytic Processes and Environmental Chemistry, Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research Demokritos , Athens , Greece"},{"name":"Department of Biomaterials, School of Dentistry, National and Kapodistrian University of Athens , Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anastasia","family":"Hiskia","sequence":"additional","affiliation":[{"name":"Photo-Catalytic Processes and Environmental Chemistry, Institute of Nanoscience and Nanotechnology, National Centre for Scientific 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