Use of an Intra-oral Model to Evaluate 0.05% Sodium Fluoride Mouthrinse in Radiation-induced Hyposalivation

The present study was undertaken to evaluate the effect of a twice-daily topical application of a 0.05% NaF mouthrinse on de- and remineralization in the oral cavities of subjects suffering from radiation-induced hyposalivation. Six subjects each wore a bonded intra-oral appliance containing a sound and a demineralized human enamel slab for four weeks. During that period, the subjects used 0.05% NaF rinses, twice daily, instead of the 1.1% NaF gel that had previously been a part of their preventive regimen. Salivary flow rates, plaque pH profiles following a 10% sucrose rinse, S. mutans and lactobacillus counts, fluoride clearance, and enamel microhardness were determined during the study. Sound enamel samples displayed no evidence of demineralization, and the previously demineralized enamel showed remineralization in the outer 50 μm in three of the six subjects. The results suggest that a twice-daily oral rinse with 0.05% NaF can prevent demineralization and enhance remineralization in subjects with radiation-induced hyposalivation.