Fluoride-uptake, Remineralization, and Micro-CT Characterization of In-office Fluoride Treatment

Objectives: This study investigated the fluoride uptake and remineralization/ demineralization behavior of different in-office fluoride treatments with various methods.
Methods: Fluoride Varnish, 3M; Nupro 1minute gel, Dentsply; Experimental NaF coating, 3M; and artificial saliva were investigated. Bovine teeth were obtained from a packing plant/slaughter house. Bovine enamels were prepared and demineralized to establish lesions. Indentations were made on enamels to measure micro-hardness(VHN). The specimens were treated with products for certain amount of time and stored in 37^oC artificial saliva to reach 24hrs. Then acid challenge was performed at 37^oC for 24hrs; then specimens were stored in artificial saliva for another 24hrs; then another acid challenge was performed for 24hrs. The VHN were measured at every step. Fluoride-uptakes were measured by biopsy method. The average VHN of the groups were statistically not different by stratification before treatments. Fluoride-uptake and VHN were compared using one-way ANOVA (p<0.05).
Results: There were significant differences between control and fluoride-treatment after acid challenge for VHN and fluoride-uptake. There was no significant difference among three fluoride treatments for VHN after challenge.
Conclusions: This study showed all fluoride treatments had superior demineralization resistance efficacy compared with artificial saliva under acid-challenge.