{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:44:15Z","timestamp":1760233455328,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,13]],"date-time":"2021-01-13T00:00:00Z","timestamp":1610496000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The aim of this preliminary study was to evaluate the short-term changes of occlusal contacts and muscle activity after orthodontic treatment during the use of a multi-layer clear retainer. Evaluation was done with the T-scan and BioEMG systems. A total of 18 subjects were included, who were evaluated at three time intervals\u2014T0 at debonding, T1 at one month after retainer delivery, and T2 at four months after retainer delivery. The T-scan and electromyography (EMG) data were recorded simultaneously. The T-scan system recorded the occlusion time, disclusion time and force distribution. The EMG waves were quantified by calculating the asymmetry index and activity index. The time variables changed but not significantly. Occlusal force decreased in the anterior dentition and increased in the posterior dentition during T0\u2013T2. There was no clear evidence of a relationship between unbalanced occlusal forces and muscle activity. In most subjects, the temporalis anterior muscle was more dominant than the masseter muscle. From this preliminary computerized study, there were no significant changes in the state of the occlusion or muscle activity during the short-term retention period.<\/jats:p>","DOI":"10.3390\/s21020541","type":"journal-article","created":{"date-parts":[[2021,1,13]],"date-time":"2021-01-13T21:50:54Z","timestamp":1610574654000},"page":"541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Computerized Assessment of Occlusion and Muscle Activity during Use of a Multilayer Clear Retainer: A Preliminary Study"],"prefix":"10.3390","volume":"21","author":[{"given":"Kyoung Yeon","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Orthodontics, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9094-2194","authenticated-orcid":false,"given":"Jin-Young","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5508-289X","authenticated-orcid":false,"given":"Song Hee","family":"Oh","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Radiology, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"given":"Hyung-Wook","family":"Moon","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5030-1894","authenticated-orcid":false,"given":"Seong-Hun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"given":"Hyo-Won","family":"Ahn","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"given":"Kyung A","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Graduate School, Kyung Hee University, Seoul 02447, Korea"}]},{"given":"Gerald","family":"Nelson","sequence":"additional","affiliation":[{"name":"Division of Orthodontics, Department of Orofacial Science, University of California San Francisco, San Francisco, CA 94143, USA"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,13]]},"reference":[{"key":"ref_1","first-page":"CD002283","article-title":"Retention procedures for stabilising tooth position after treatment with orthodontic braces","volume":"2016","author":"Littlewood","year":"2016","journal-title":"Cochrane Database Syst. 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