Abstract: Objective To study the effect of naringin solution with different concentration on the remineralization of early enamel caries. Methods Models of early enamel caries of human premolars were established by external demineralization method. The samples were remineralized with different concentrations of naringin solution, NaF and deionized water (DW) as positive and negative controls, respectively. The changes of image and the ratio of calcium and phosphorus of melt surface before and after demineralization were observed by electron probe and Xray energy spectrometer. Results The results of electron probe showed that the enamel surface of the deionized water group showed a typical demineralization, which was a honeycomb loose structure. The NaF group could form a uniform spherical sedimentary area. Irregular sediments covered the honeycomb surface of the demineralization in naringin solution groups, and with the increase of concentration, the sediments gradually changed from porous to dense. The Ca/P in the experimental group was lower than that in the NaF group (P＜0.05). The Ca/P in the 1, 10, 20 and 50 mg/mL naringin solution groups was similar to that in the DW group, and the difference was not statistically significant. Compared with 1, 10 mg/mL naringin solution groups and DW group, 100 mg/mL naringin solution group had statistical significance (P＜0.05). Conclusion Different concentrations of naringin solution can promote the remineralization of early enamel caries, and the effect of naringin solution increases with the increase of concentration.

Key words: naringin, early enamel caries, demineralization, remineralization