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Lubrication was measured using an ex vivo tongue-enamel friction system in terms of Relief and Relief period. MUC5b and total protein concentrations of the saliva samples were measured by an enzyme-linked immunosorbent assay and a bicinchoninic acid assay, respectively.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Relief of Sj\u00f6gren\u2019s patients\u2019 saliva and post-irradiation patients\u2019 saliva was similar compared with healthy controls, but saliva from post-irradiation patients lubricated significantly better than saliva from Sj\u00f6gren\u2019s patients. The Relief period was similar between the three groups. The Relief and Relief period were higher for saliva samples post-irradiation compared to pre-irradiation. MUC5b and total protein concentrations were comparable in all groups. MUC5b and total protein output were significantly lower in patients subjected to radiotherapy compared to saliva from healthy controls and pre-irradiation patients. MUC5b concentrations positively correlated with lubricating properties of post-irradiation patient saliva.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>The lubricating properties of patient saliva were not any worse than healthy controls. Lower flow rate leads to lower availability of saliva in the oral cavity and decreases the overall output of protein and MUC5b, which might result in an insufficient replenishing of the mucosal salivary film.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Clinical relevance<\/jats:title>\n                <jats:p>An insufficient replenishing might underlie the sensation of a dry mouth and loss of oral function.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00784-020-03758-8","type":"journal-article","created":{"date-parts":[[2021,3,4]],"date-time":"2021-03-04T05:02:57Z","timestamp":1614834177000},"page":"4459-4469","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Lubricating properties of chewing stimulated whole saliva from patients suffering from xerostomia"],"prefix":"10.1007","volume":"25","author":[{"given":"Jeroen","family":"Vinke","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marijn","family":"Oude Elberink","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monique A.","family":"Stokman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frans G. 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