Changes in Demineralized Enamel around Brackets Detected by Laser Fluorescence Following Fluoride Treatment

Abstract

Objective: To evaluate in-vitro, using red laser-light induced fluorescence (LF), the effect of three fluoride compounds on the demineralization-remineralization process around brackets bonded with glass ionomer cement (GIC) or resin-based cement. Materials and method: The material comprised a sample of 60 premolars. 30 brackets were bonded with resin and 30 with glass ionomer cement. The enamel around the bracket was exposed to three demineralization? remineralization cycles to create a white spot lesion. After each cycle a fluorescent dye was applied to the enamel to measure laser fluorescence using a DIAGNOdent LF2190. The lesions were remineralized with three different commercial products: 12,000 ppm fluoride, 1,500 ppm fluoride, and 900 ppm fluoride. After pH cycles, the tooth received three weekly fluoride treatments and LF measurements with the dye were taken. Results: The initial LF values of the enamel around resin-bonded (2.0 ? 0.94) or GIC-bonded brackets (1.86 ? 0.62) showed no differences (p>0.05). After pH cycling, LF values showed no difference between the groups. The LF mean was 15.15 ? 4.28. The three fluoride compounds produced enamel remineralization around the brackets. Following fluoride treatment, a score was created based on the difference between LF post fluoride treatment and the initial LF values. These LF values showed statistical differences (p<0.001). Treatment with 900 ppm fluoride produced the highest remineralization values in both the resin and the GIC group. Conclusion: The three fluoride compounds tested had the ability to remineralize enamel lesions produced by pH cycling around brackets bonded with resin or GIC.