Ex vivo approach to studying bio-adhesive and tribological properties of artificial salivas for oral dryness (xerostomia)

Saliva plays fundamental role in the maintenance of the good mouth health and in the lubrication process during oral functions including speech and mastication. Xerostomia, or dry mouth syndrome, is a disease due to an insufficient saliva secretion, or a total absence of saliva. The effects of xerostomia are very unpleasant in the daily life. They lead to some important inconveniences as the dental caries, the loss of teeth or some difficulties to speak.The causes of xerostomia are various but the most of the times they are often associated to irradiation and radiotherapy used to treat cancers of the head and neck. To try to re-wet the oral cavity, salivary substitutes are generally used. They are supposed to re-lubricate the mouth.In this work, a method for measuring adhesion and lubrication of the salivary substitutes has been tested ex vivo on pig tongue. The results indicated that the bio-adhesive properties of the salivary substitutes were fairly close to those of human saliva, while their lubricate capacity were rather less efficient. The experimental method proposed here seems to be interesting to characterise and improve the salivary substitutes performances.