Effect of fluoride releasing orthodontic sealants on enamel demineralization in vitro / 대한치과교정학회지

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).

The effects of fluoride releasing orthodontic sealants on the prevention and the progressive inhibition of enamel demineralization in vitro / 대한치과교정학회지

The purpose of this study was to identifu the preventive and the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Group G'). For polarzing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at 45degrees to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high0vacuum evaporator* and examined in an ISI-100B scanning electron microcpe** operated at 20kV. The results of this study were as follows : 1. The mean deoths of artificial carious lesions under a polarized light microscope were Group A(5.08microgram), Group B(47.82microgram), Group C(8.42microgram), Group D(7.20microgram), Group E(85.41microgram), Group F(60.38microgram), Group G(60.13microgram). 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group E compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects enamel demineralization. 5. The time progress of demineralizing agent no ingluecse on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic edalants both in the polarized light microscopic group and in the scanning electron microscopic group. *Hitachi Ltd, Tokyo, Japan **International Scientific Instruments, Santa Clara, Calif.