ผลของเจลข้าวฟลูออไรด์ต่อการต้านทานกรดในชั้นเคลือบฟันมนุษย์

Abstract

Objective: To investigated the effect of fluoride rice gel on acid resistance improvement of buman enamel compared to commercial fluoride gel. Methods: 30 human molars were prepared by cutting teeth into two halves mesio - distally then polished with 2000 grits sandpaper and coated with nail varnish to protect the surface except 3x1 mm' of exposure cite. The specimens were randomly divided into 4 groups; each group contains 15 samples. Group 1, the specimens were applied with placebo rice gel (PL). Group 2, the specimens were applied with commercial 1.23% acidulated phosphate fluoride gel (APF gel) (60-second gel, Germiphene corporation, Canada) (AP). Group 3, the specimens were applied with neutral 2% sodium luoride rice gel. (RS) Group 4, the specimens were applied with 1.23% acidulated phosphate fluoride rice gel (RA). All specimens were immersed in remineralization and demineralization solution for 7 days to replicated pH-cyeling. After pH cycling, all specimens were tested with microcomputed tomography (µCT 35, Scanco, Switzerland) for mineral density, digital microhardness tester (Startech SMV-1000, Guiyang Sunproc International Trade Co.,Ltd., Guiyang, China) for surface hardness then were cut cross-sectionally and tested with microhardness tester for cross-sectional microhardness (CSMH). Mineral density changing percentage data and surface microhardness data were statistically analyzed by one-way ANOVA and cross-sectional microhardness data were analyzed by two-way ANOVA (p<0.05) with Tukey's post hoc test. Results: Considering surface microhardness values after pH cyeling, AP group showed the highest value and least of value changing. Nevertheless, there was no difference between AP and RA group. PL group show the highest loss of mineral in percentage of mineral density change, and there was no difference between AP group and RA group. CSMH values presented no difference between AP and RA group from 65 microns to 115 microns from outer surface presented no difference in every group. Conclusions: Both formulas of fluoride rice gel provided acid resistance enhancement to human enamel. Gelling agent made from rice could be used to contain fluoride content in high concentration and released to human enamel resembled to commercial fluoride gel.