We designed 3-phase in vivo experiments to measure fluoride concentrations in saliva and in distilled water, in which removable appliance were immersed through seven days. The subjects had worn acrylic removable appliance, while night sleeping, in which glass ionomer cement specimen was embedded(experiment I). In addition, after using fluoride toothpaste or fluoride mouth rinse, they had worn their own appliances(experiment II). And after fluoride toothpaste or fluoride solution were applied directly on the external surface glass ionomer specimens(experiment III), fluoride storage capacity of the glass ionomer cement specimens was measured. The results were as follows.
1. Fluoride concentrations in saliva and in distilled water used for storing appliance were measured(experiment I). Fluoride concentrations in saliva were significantly increased to 4.71μ㏖/ℓ in the first day(p<0.05).
2. After using fluoride toothpaste or fluoride mouth rinse, the subjects had worn appliances(experiment II), salivary fluoride concentrations in fluoride mouth rinse group increased to 69.09μ㏖/ℓ. These were higher concentrations of salivary fluoride than fluoride toothpaste use group(p<0.01). Fluoride concentrations of distilled water in which appliances were immersed not significantly different between fluoride toothpaste and fluoride mouth rinse group.
3. After fluoride toothpaste or fluoride solution was applied directly to glass ionomer specimen(experiment III), fluoride concentrations in saliva and distilled water were measured. In the group of fluoride rinse and soaking appliance in fluoride solution, salivary fluoride concentrations increased to 452.89μ㏖/ℓ, higher than fluoride toothpaste group in the first day(p<0.01). Besides, fluoride concentrations in distilled water increased to 32.65μ㏖/ℓ, also higher than toothpaste group(p<0.05).
According to the results, salivary fluoride concentrations after wearing glass ionomer cement specimen embedded while sleeping decreased rapidly one day after. It is concluded from this study that embedding glass ionomer cement specimens into the orthodontic removable appliance and soaking these appliance in the fluoride solution might be effective measure for the use of slow releasing fluoride from the specimens.