{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T14:57:36Z","timestamp":1775141856719,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2019,8,6]],"date-time":"2019-08-06T00:00:00Z","timestamp":1565049600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP19K12828"],"award-info":[{"award-number":["JP19K12828"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We intend to develop earphone-type wearable devices to measure occlusal force by measuring ear canal movement using an ear sensor that we developed. The proposed device can measure occlusal force during eating. In this work, we simultaneously measured the ear canal movement (ear sensor value), the surface electromyography (EMG) of the masseter muscle and the occlusal force six times from five subjects as a basic study toward occlusal force meter development. Using the results, we investigated the correlation coefficient between the ear sensor value and the occlusal force, and the partial correlation coefficient between ear sensor values. Additionally, we investigated the average of the partial correlation coefficient and the absolute value of the average for each subject. The absolute value results indicated strong correlation, with correlation coefficients exceeding 0.9514 for all subjects. The subjects showed a lowest partial correlation coefficient of 0.6161 and a highest value of 0.8286. This was also indicative of correlation. We then estimated the occlusal force via a single regression analysis for each subject. Evaluation of the proposed method via the cross-validation method indicated that the root-mean-square error when comparing actual values with estimates for the five subjects ranged from 0.0338 to 0.0969.<\/jats:p>","DOI":"10.3390\/s19153441","type":"journal-article","created":{"date-parts":[[2019,8,7]],"date-time":"2019-08-07T03:09:08Z","timestamp":1565147348000},"page":"3441","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Simultaneous Measurement of Ear Canal Movement, Electromyography of the Masseter Muscle and Occlusal Force for Earphone-Type Occlusal Force Estimation Device Development"],"prefix":"10.3390","volume":"19","author":[{"given":"Mami","family":"Kurosawa","sequence":"first","affiliation":[{"name":"Interdisciplinary Graduate School of Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan"},{"name":"Graduate School of Engineering Science, Osaka University, 1\u20133 Machikaneyama, Toyonaka, Osaka 560-8531, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5774-5124","authenticated-orcid":false,"given":"Kazuhiro","family":"Taniguchi","sequence":"additional","affiliation":[{"name":"Graduate School of Information Sciences, Hiroshima City University, 3-4-1 Ozukahigashi, Asaminami-ku, Hiroshima 731-3194, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hideya","family":"Momose","sequence":"additional","affiliation":[{"name":"SKINOS Nagano Co., Ltd., 2-16-24 Fumiiri, Ueda, Nagano 386-0017, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masao","family":"Sakaguchi","sequence":"additional","affiliation":[{"name":"SKINOS Tohmi Lab., 3100-5 Kano, Tomi, Nagano 389-0505, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masayoshi","family":"Kamijo","sequence":"additional","affiliation":[{"name":"Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5669-1726","authenticated-orcid":false,"given":"Atsushi","family":"Nishikawa","sequence":"additional","affiliation":[{"name":"Graduate School of Engineering Science, Osaka University, 1\u20133 Machikaneyama, Toyonaka, Osaka 560-8531, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"445","DOI":"10.1016\/S0039-6109(16)45689-6","article-title":"Postgastrectomy syndromes","volume":"72","author":"Eagon","year":"1992","journal-title":"Surg. 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