research and knowledge

Randomized, placebo controlled, double-blind study

Van der Reijden WA et al., (1996) examined in a randomized, double-blind, placebo-controlled trial the efficacy of 3 types of polymer-based saliva substitutes in reducing oral dryness in 43 patients (aged 25-79 years) with primary and secondary Sjögren’s syndrome for total 7 week. Participants were randomly assigned to receive carbopol (polyacrylic acid) saliva substitute (group A), xanthan gum saliva substitute (group B), saliva Orthana (commercial prepared saliva substitute; group C) and placebo (group D). Products all used ad libitum for 1 week. Duration of intervention: 4 x 1-week test periods with 1-week washouts in between (total 7 weeks). Salivary flow rates (SFR) were determined to examine correlations between the salivary flow rates and the subjective efficacy of the saliva substitute.

Neither the saliva substitutes nor the placebo was truly effective. Preference for a particular saliva substitute over placebo was equally distributed among the 3 types of substitutes. The salivary flow rates of patients who preferred polyacrylic acid-based saliva substitutes was lower than that in patients who preferred the porcine mucin-based substitute (p < 0,05). Patients whose oral dryness was reduced by low-viscoelastic substitutes had a low stimulated salivary flow rates ( < 0,20 ml/minute; p < 0,05).

No side effects from the saliva substitutes were observed during the study.

Authors concluded that the optimal properties of a saliva substitute are not the same for all patients with Sjögren’s syndrome, but are dependent on such parameters as the individual salivary flow rates . Thus, to determine the best saliva substitute for a particular patient, it is necessary to have the patient try a number of substitutes of different viscoelastic properties.

Read all: