{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T12:57:58Z","timestamp":1763729878359,"version":"3.45.0"},"reference-count":26,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T00:00:00Z","timestamp":1763683200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Saliva sampling is increasingly used for respiratory virus diagnostics in dentistry and oral medicine due to patient comfort and reduced exposure risk. How routine behaviors\u2014mechanical oral hygiene, rinsing, and food intake\u2014affect short-term SARS-CoV-2 detectability remains insufficiently characterized for clinical workflows. Methods: In this international two-center pilot study, twelve RT-PCR-confirmed COVID-19 patients provided paired mouth-rinse saliva samples and pharyngeal swabs at predefined time points. The study assessed (I) an intensified 3 min mechanical oral hygiene protocol (toothbrushing of teeth, gingiva, tongue, and palate, followed by toothpaste\u2013saliva gargling); (II) repeated short mouth rinses; and (III) postprandial sampling. Viral RNA was quantified by RT-PCR; Ct-trajectories were analyzed intra-individually. Results: Cycle threshold (Ct) values from pharyngeal swabs remained relatively stable over time, whereas mouth-rinse samples exhibited notable fluctuations throughout the 24 h period. An average increase of 3 Ct units was observed three minutes after the final mouth rinse (T24+3). Meal ingestion was associated with increased Ct values, rising by 4\u20135 units for pharyngeal swabs and 3\u201311 units for mouth rinses immediately after eating. Conclusions: In clinical dental settings, saliva diagnostics are feasible but acutely modulated by common behaviors. Mechanical oral hygiene, brief rinsing, and food intake can transiently reduce detectable oral SARS-CoV-2 RNA, with potential implications for timing of sampling, chairside triage, and infection-control protocols. This pilot study provides initial evidence supporting the development of standardized pre-analytical instructions (e.g., fasting window, pre-rinse policy, and sampling timing relative to oral hygiene and meals) to enhance the reliability of saliva-based testing in dental care.<\/jats:p>","DOI":"10.3390\/jcm14238280","type":"journal-article","created":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T12:41:58Z","timestamp":1763728918000},"page":"8280","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Rinsing a Pandemic Down: Effects of Oral Hygiene in SARS-CoV-2: A Two-Center Prospective Pilot Study"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-3555-1971","authenticated-orcid":false,"given":"Philipp","family":"Ehrmann","sequence":"first","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Anichstra\u00dfe 35, 6020 Innsbruck, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carolin","family":"Goetz","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Anichstra\u00dfe 35, 6020 Innsbruck, Austria"},{"name":"Department of Oral and Maxillofacial Surgery, TUM School of Medicine and Health, Technical University of Munich, Klinikum Rechts der Isar, Ismaninger Strasse 22, 81675 Munich, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Holger","family":"Bock","sequence":"additional","affiliation":[{"name":"Office for Knowledge and Technology Transfer, University of Innsbruck, Technikerstr. 21a, 6020 Innsbruck, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lena","family":"Denk","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Anichstra\u00dfe 35, 6020 Innsbruck, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4660-1883","authenticated-orcid":false,"given":"Petr","family":"Posta","sequence":"additional","affiliation":[{"name":"Department of Stomatology, University Hospital Pilsen, Faculty of Medicine, Charles University, 32300 Pilsen, Czech Republic"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Herbert","family":"Deppe","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, TUM School of Medicine and Health, Technical University of Munich, Klinikum Rechts der Isar, Ismaninger Strasse 22, 81675 Munich, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elisabeth","family":"Maier","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Anichstra\u00dfe 35, 6020 Innsbruck, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Oliver","family":"Bissinger","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Surgery, Medical University Innsbruck, Anichstra\u00dfe 35, 6020 Innsbruck, Austria"},{"name":"Department of Oral and Maxillofacial Surgery, TUM School of Medicine and Health, Technical University of Munich, Klinikum Rechts der Isar, Ismaninger Strasse 22, 81675 Munich, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1353","DOI":"10.1016\/S0140-6736(03)14630-2","article-title":"Epidemiology and cause of severe acute respiratory syndrome (SARS) in Guangdong, People\u2019s Republic of China, in February, 2003","volume":"362","author":"Zhong","year":"2003","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1038\/nrmicro.2016.81","article-title":"SARS and MERS: Recent insights into emerging coronaviruses","volume":"14","author":"Falzarano","year":"2016","journal-title":"Nat. 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