ABSTRACT
The purpose of this study was to evaluate the effects of fluoride releasing orthodontic sealants, light-cured(Group L1 & L2) and self-cured (Group S1 & S2) FluoroBond(R) , on enamel microhardness under artificial carious solution in vitro 112 extracted human premolar teeth were collected for experiments and divided into seven groups. A Tukon microhardness tester equipped with a Knoop diamond indenter was employed to determine microhardness. Tukon 23 program converted the number of microhardness into KHN(Knoop hardness number). The results were as follows : 1. The microhardness of enamel depth of all groups were the least at the depth of 50micrometer and that of all groups except L2 group, the greatest at the depth of 200micrometer, were the greatest at the depth of 300micrometer. And as the enamel depth of all groups except L2 and S2 group increased, the microhardness value also increased. 2. There was a little preventive effect in enamel decalcification both light-and self-cured orthodontic sealant groups, but had no statistical significance between the groups(p>0.05). 3. Light-cured ortodontic sealant groups had a progressive inhibiting effect in enamel decalcification at the depth of 100micrometer, 150micrometer, and 200micrometer(p0.05).