{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T20:19:32Z","timestamp":1769026772553,"version":"3.49.0"},"reference-count":32,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,7,4]],"date-time":"2023-07-04T00:00:00Z","timestamp":1688428800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinics and Practice"],"abstract":"<jats:p>This cross-sectional study aimed to examine the relationships between lip seal strength, tongue pressure, and daytime sleepiness in Japanese workers. A self-administered questionnaire which comprised the Epworth Sleepiness Scale (ESS) was completed by 496 workers, and excessive daytime sleepiness was defined by an ESS score of 11 or over. Lip seal strength and tongue pressure were measured in all participants, and multiple regression analyses were performed to examine the effects of lip seal strength and tongue pressure on daytime sleepiness. The median ESS score was 5.0 (25th and 75th percentiles: 2.0 and 8.0), and 42 (8.5%) workers had excessive daytime sleepiness. The median lip seal strength was 13.5 N (11.4, 16.3), and the tongue pressure was 41.7 kPa (35.2, 48.3). Workers with higher ESS scores had significantly lower levels of lip seal strength than those without, following adjustments for age and body mass index (BMI) values (\u03b2 (95% confidence interval): \u22120.043 [\u22120.081, \u22120.004]). However, tongue pressure was not significantly associated with ESS score after adjustments for age and\/or BMI. These results suggest that maintaining moderate lip seal strength may help prevent excessive daytime sleepiness in Japanese workers regardless of age or BMI.<\/jats:p>","DOI":"10.3390\/clinpract13040068","type":"journal-article","created":{"date-parts":[[2023,7,5]],"date-time":"2023-07-05T00:53:04Z","timestamp":1688518384000},"page":"753-762","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Relationships between Lip Seal Strength, Tongue Pressure, and Daytime Sleepiness in Japanese Workers: A Cross-Sectional Study"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9805-508X","authenticated-orcid":false,"given":"Akira","family":"Minoura","sequence":"first","affiliation":[{"name":"Department of Hygiene, Public Health and Preventive Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yoshiaki","family":"Ihara","sequence":"additional","affiliation":[{"name":"Division of Oral Functional Rehabilitation Medicine, Department of Special Needs Dentistry, School of Dentistry, Showa University, 2-1-1 Kitasenzoku, Ohta-ku, Tokyo 145-8515, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hirotaka","family":"Kato","sequence":"additional","affiliation":[{"name":"Division of Oral Functional Rehabilitation Medicine, Department of Special Needs Dentistry, School of Dentistry, Showa University, 2-1-1 Kitasenzoku, Ohta-ku, Tokyo 145-8515, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kouzou","family":"Murakami","sequence":"additional","affiliation":[{"name":"Department of Radiology, Division of Radiation Oncology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5091-8210","authenticated-orcid":false,"given":"Yoshio","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Division of Respiratory Medicine and Allergology, Department of Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4466-7953","authenticated-orcid":false,"given":"Kojiro","family":"Hirano","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology Head and Neck Surgery, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yoshinori","family":"Ito","sequence":"additional","affiliation":[{"name":"Department of Radiology, Division of Radiation Oncology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2252-3542","authenticated-orcid":false,"given":"Akatsuki","family":"Kokaze","sequence":"additional","affiliation":[{"name":"Department of Hygiene, Public Health and Preventive Medicine, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1717","DOI":"10.1007\/s00125-021-05463-x","article-title":"A UK nationwide study of people with type 1 diabetes admitted to hospital with COVID-19 infection","volume":"64","author":"Ruan","year":"2021","journal-title":"Diabetologia"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1302","DOI":"10.1016\/S0140-6736(16)30370-1","article-title":"Does physical activity attenuate, or even eliminate, the detrimental association of sitting time with mortality? 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