Betaine-containing toothpaste relieves subjective symptoms of dry mouth

Subjects with dry mouth often experience irritation of the oral mucosa when using sodium lauryl sulfate containing products for oral hygiene. Betaine, or trimethylglycine, reduces skin-irritating effects of ingredients of cosmetics such as sodium lauryl sulfate. The aim of the present study was to compare the effects of a betaine-containing toothpaste with a regular toothpaste on the oral microbial flora, the condition of the oral mucosa, and subjective symptoms of dry mouth in subjects with chronic dry mouth symptoms. Thirteen subjects with chronic dry mouth symptoms and with a paraffin-stimulated salivary flow rate < or = 1 mL/min participated in the double-blind crossover study. Ten subjects had a very low salivary flow rate (< or = 0.6 mL/min). The subjects used both experimental toothpastes (with or without 4% betaine) twice a day for 2 weeks. Oral examinations and microbiologic sample collections were made at the base lines preceding the two experimental periods and at the end. Standardized questions on subjective symptoms of dry mouth were used when the subjects were interviewed at the end of the two experimental periods. No study-induced significant changes were observed in the microbiologic variables (plaque index, mutans streptococci, lactobacilli, Candida species) or in the appearance of the oral mucosa. The use of the betaine-containing toothpaste was, however, associated with a significant relief of several subjective symptoms of dry mouth. Betaine appears thus to be a promising ingredient of toothpastes in general and especially of toothpastes designed for patients with dry mouth.