Abstract: PURPOSE: To evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) combined with different concentrations of fluoride on demineralization of enamel remineralization. METHODS: Extracted premolar teeth for orthodontic reason were immersed into lactic acid gel to prepare artificial white spot lesions. Then the specimens were randomly assigned to 3 groups: 5% CPP-ACP group as control, 5% CPP-ACP +500 mg/L F- group and 5% CPP-ACP +900 mg/L F- group, which were measured by micro-hardness tester. SPSS 18.0 software package was used for data analysis. RESULTS: There were significant differences in micro-hardness between control group and experimental group 1 and experimental group 2 by SNK-q test (P<0.05). CONCLUSIONS: CPP-ACP can make the demineralization of enamel remineralization occurs. F can promote the CPP-ACP remineralization. The increase of fluoride can make the CPP-ACP remineralization better below 1000-1500 mg/L.

Key words: APP-ACP, Florid, Enamel remineralization, Micro-hardness