Objectives: The purpose of this study was to evaluate amount of fluoride release and tooth fluoride uptake from a new glass-ionomer, Gold Label HS posterior EXTRA(EX).
Methods: Molds with a hole(7mm x 1mm) were filled with mixed EX and Fuji IX GP(F9). The specimens were stored in a chamber with 100%R.H. at 37°C for 1hour, then each specimens were immersed in distilled water(8mL) at 37°C. The amount of released fluoride in distilled water was measured by a fluoride detective electrode(IM-40S, TOA) after 1day, 3days and 7days(n=5).
Bovine anterior teeth were cross-sectioned to 2mm thick at center of coronal portion and surfaces were roughened with 600-grit paper. Cavity Conditioner (GC) was applied to roughened surface. EX and F9 were filled into the rings (15mm x 1mm). Specimens were stored in a chamber with 100%R.H. at 37°C for 10minutes. Teeth samples were put on glass-ionomer discs and immersed in 4mL 20mM HEPES buffer(pH7.0) at 37°C for 1week. Samples were washed with distilled water and fluoride content of dentin surfaces contacted with glass-ionomer discs at 100micro-m from enamel/dentin junction were measured with Energy Dispersed Spectroscopy(EDS, OXFORD INCA pentaFETx3, n=5).
The data was analyzed by t-test.
Results: Fluoride release and tooth fluoride uptake from EX was significantly higher than F9.
Conclusion: Test results indicate that EX has excellent fluoride release and its diffusion into bovine dentine.
| Cumulative amount of fluoride release after 7days(micro-g/cm2) | Fluoride content in dentin after 7days(wt%) |
Before soaking | - | Undetectable |
EX | 244(21) | 1.51(0.29) |
F‚X | 108(9)** | 0.27(0.16)** |
():S.D., **:p<0.01