Primary Sjögren’s syndrome (SS) is a systemic autoimmune disorder characterised by a chronic, progressive loss of salivary and lacrimal function resulting in symptoms of oral and ocular dryness. The involvement of exocrine glands is the result of a focal, periductal mononuclear cell infiltrate and the subsequent loss of secretory epithelial cells.1 As a consequence, major changes occur in both the salivary flow rate and salivary composition.2-9 In the case of secondary SS a second autoimmune disease is involved, mostly rheumatoid arthritis.

The role of saliva in maintaining oral health and even quality of life is obvious in people who are lacking sufficient saliva.10-12 The effects of the reduced salivary flow rate (xerostomia) and changed salivary composition in SS are apparent (table 1): there are problems in eating, speaking, and swallowing12-15 and frequently disturbances in taste perception.16 In addition, reduced clearance of food, changes in microbial ecology and a reduced buffer capacity have their effects on oral health: an increased susceptibility to dental caries and oral infections are important clinical manifestations of the oral component of SS.17 ,18 When the systemic disease advances, salivary secretion declines further.7

A reduction of the salivary flow rate below physiological values can be induced by several other causes as well.19 Dry mouth symptoms are known as a side effect of more than 400 drugs.20 ,21 In most of these cases the level of reduction of the salivary flow is slight and can be compensated for by mechanical or gustatory stimulation. Other common causes of prolonged hyposalivation include other autoimmune disorders such as systemic lupus erythematosus,22 ,23 uncontrolled diabetes mellitus24 ,25 and salivary gland injury as a result of radiotherapy in the head and neck region.26

This …