2009 Volume 47 Issue 5 Pages 760-766
An infant's salivary fluoride concentration was measured by a flow injection analysis device that can measure ultratrace amounts of fluoride ion concentrations, to obtain basic data on the fluoride (F) ionic level in the mouth.One hundred and one 4- to 6-year-old kindergarteners (44 boys and 57 girls) in two day nurseries participated in this study. Stimulated saliva samples were collected. These collections were taken 2 hours or more after breakfast and before lunch. The saliva samples were centrifuged and then the F ionic level was measured in 0.2 ml of the supernatant using the flow injection analysis device. Moreover, a standardized solution (0.05, 0.1, 0.5 ppmF) was added to the saliva at a rate of 1 : 9, and then the temporal change of the F ionic level was measured. The reproducibility of the measurement of the infant's salivary fluoride concentration was high and this device showed an excellent stability. The mean (SD, min-max) salivary F concentration was 0.0082 (0.0026, 0.0017−0.017) ppmF. No gender difference and no age difference was observed. A significant difference was observed between the children in the two day nurseries and the F ionic level of those in the day nursery. A kindergartener who was using a fluoride mouth wash showed a high value. The F ion concentration in the saliva that contained the additional F showed a decrease of 17−45% in comparison to the F ion concentration of purified water that contained F.It was thought that the measurement of the density of F ions in the infant's saliva by means of a flow injection analysis device was effective because the F ionic levels of the infant's saliva were all below the measurement limits of the conventional F ion electrode method.
