{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T13:44:35Z","timestamp":1792071875840,"version":"4.4.0"},"reference-count":20,"publisher":"Wiley","issue":"4","license":[{"start":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T00:00:00Z","timestamp":1784160000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T00:00:00Z","timestamp":1784160000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Clinical &amp; Exp Dental Res"],"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Aims<\/jats:title>\n                    <jats:p>To investigate longitudinal alterations in oral hygiene, gingival inflammation, and salivary secretion during a 60\u2010day head\u2010down tilt bed rest (HDTBR) protocol as a validated ground\u2010based analog of microgravity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and Methods<\/jats:title>\n                    <jats:p>Twenty\u2010four healthy volunteers participated in a 60\u2010day, 6\u00b0 HDTBR study conducted under strictly controlled conditions. Oral health assessment safety measures were performed at baseline, mid\u2010head\u2010down tilt (HDT), end\u2010HDT, and post\u2010recovery.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Plaque accumulation and gingival inflammation increased, with increases from baseline to end\u2010HDT in the Quigley\u2010Hein Plaque Index (1.8\u2009\u00b1\u20090.4 to 2.3\u2009\u00b1\u20090.4;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.01), Gingival Index (0.8\u2009\u00b1\u20090.4 to 1.2\u2009\u00b1\u20090.2;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001), and bleeding on probing (BoP) (18.4\u2009\u00b1\u200911.6% to 35.1\u2009\u00b1\u200916.6%;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001). BoP partially recovered post\u2010HDT, while QHI and GI remained elevated compared with baseline. Periodontal Screening Index scores shifted toward higher grades during HDT without evidence of destructive periodontal breakdown. The unstimulated salivary flow rate remained unchanged throughout.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Prolonged gravitational unloading induces a plaque\u2010driven deterioration of gingival health in systemically healthy individuals, likely related to impaired mechanical plaque control and microcirculatory changes rather than salivary dysfunction. Gingival tissues appear to be sensitive biomarkers of adaptation to unloading conditions, supporting the need for optimized oral hygiene and adjunctive preventive strategies during future long\u2010duration space missions.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial Registration<\/jats:title>\n                    <jats:p>\n                      German Clinical Trial Registry (DRKS00033882, registration date 03\u201015\u20102024,\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"https:\/\/www.drks.de\/search\/de\/trial\/DRKS00033882\/details\">https:\/\/www.drks.de\/search\/de\/trial\/DRKS00033882\/details<\/jats:ext-link>\n                      ).\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/cre2.70412","type":"journal-article","created":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T18:18:03Z","timestamp":1784225883000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Understanding Oral Hygiene and Periodontal Health in Space Using a Bedrest Analog Model for Weightlessness (NASA Sensorimotor Countermeasures Study)"],"prefix":"10.1002","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2239-6010","authenticated-orcid":false,"given":"Sonja Henny Maria","family":"Derman","sequence":"first","affiliation":[{"name":"Faculty of Medicine and University Hospital Cologne, Polyclinic for Operative Dentistry and Periodontology, University of Cologne Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laura","family":"de Boni","sequence":"additional","affiliation":[{"name":"German Aerospace Center (DLR), Institute of Aerospace Medicine Cologne Germany"},{"name":"Institute of Neuropathology University Hospital Bonn Bonn Germany"},{"name":"Dementia Research Institute (DRI) University College London London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edwin","family":"Mulder","sequence":"additional","affiliation":[{"name":"German Aerospace Center (DLR), Institute of Aerospace Medicine Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"M\u00f6stl","sequence":"additional","affiliation":[{"name":"German Aerospace Center (DLR), Institute of Aerospace Medicine Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Jagel","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and University Hospital Cologne, Polyclinic for Operative Dentistry and Periodontology, University of Cologne Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3431-7749","authenticated-orcid":false,"given":"Teresa","family":"Kruse","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and University Hospital Cologne, Department of Orthodontics University of Cologne Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0169-2582","authenticated-orcid":false,"given":"Anna Greta","family":"Barbe","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and University Hospital Cologne, Polyclinic for Operative Dentistry and Periodontology, University of Cologne Cologne Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,7,16]]},"reference":[{"key":"e_1_2_12_2_1","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2024.1406631"},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.1080\/27694127.2022.2102363"},{"key":"e_1_2_12_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/s0099-2399(86)80198-4"},{"key":"e_1_2_12_5_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10439-021-02745-8"},{"key":"e_1_2_12_6_1","doi-asserted-by":"publisher","DOI":"10.1152\/jn.00065.2016"},{"key":"e_1_2_12_7_1","doi-asserted-by":"crossref","unstructured":"Hargens A. R. S. E.Parazynski D. E.Watenpaugh M.Aratow G.Murthy andY.Kawai. 1994. \u201cMechanism of Headward Fluid Shift During Exposure to Microgravity.\u201d NASA Technical Reports Server Document ID 20010124103.https:\/\/ntrs.nasa.gov\/citations\/20010124103.","DOI":"10.1016\/0928-4680(94)90745-5"},{"key":"e_1_2_12_8_1","doi-asserted-by":"publisher","DOI":"10.1111\/idh.12893"},{"key":"e_1_2_12_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.actaastro.2019.11.015"},{"key":"e_1_2_12_10_1","doi-asserted-by":"publisher","DOI":"10.3390\/life12020268"},{"key":"e_1_2_12_11_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00421-007-0474-z"},{"key":"e_1_2_12_12_1","doi-asserted-by":"publisher","DOI":"10.1139\/bcb-2025-0136"},{"key":"e_1_2_12_13_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.2041-1626.2012.00155.x"},{"key":"e_1_2_12_14_1","doi-asserted-by":"publisher","DOI":"10.1113\/ep092474"},{"key":"e_1_2_12_15_1","doi-asserted-by":"publisher","DOI":"10.1096\/fj.202503258R"},{"key":"e_1_2_12_16_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41526-025-00509-5"},{"key":"e_1_2_12_17_1","doi-asserted-by":"publisher","DOI":"10.1017\/S1473550420000105"},{"key":"e_1_2_12_18_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.lssr.2025.01.004"},{"key":"e_1_2_12_19_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41526-025-00531-7"},{"key":"e_1_2_12_20_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12979-024-00449-w"},{"key":"e_1_2_12_21_1","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00986.2015"}],"container-title":["Clinical and Experimental Dental Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/cre2.70412","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/cre2.70412","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/cre2.70412","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T12:48:52Z","timestamp":1792068532000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/cre2.70412"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,16]]},"references-count":20,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2026,8]]}},"alternative-id":["10.1002\/cre2.70412"],"URL":"https:\/\/doi.org\/10.1002\/cre2.70412","archive":["Portico"],"relation":{},"ISSN":["2057-4347","2057-4347"],"issn-type":[{"value":"2057-4347","type":"print"},{"value":"2057-4347","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,16]]},"assertion":[{"value":"2026-01-22","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-03","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-07-16","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70412"}}