The Combined Effect Of NHA And CPP-ACP On Enamel Remineralization After Acid Erosion : An In Vitro Study

Objective: This experiment explores the effect of enamel demineralization caused by carbonated drinks(Coca-Cola)after different materials treatment.Methods:50 bovine incisors with no caries pigmentation and no obvious cracks were selected and cut into5mm×5mm×2mm enamel block after silicon carbide sandpaper and exposed to the experimental window area of the enamel surface(4mm×4mm).Select 310(enamel block samples within 390 HV range,randomly divided into 5 groups: DI water-treated group,CP-ACP(casein phosphopeptide-amorphous calcium phosphate)treated group,nHA(10%20nm hydroxyapatite)treated group,nHA+CPP-ACP treated group,10 enamel blocks each.(1)Each group of enamel blocks was soaked in Coca-Cola for 7 days of acid erosion,4 times a day,Each time for 90 s,The rest of the time is stored in artificial saliva;(2)Five samples were coated with deionized water,DOfluorine,CPP-ACP,nHA,nHA+CPP-ACP on the surface of the enamel block,And 2 times a day,Enserved for 14 days,The surface hardness was detected using microscopic hardness instrument,Measure the enamel surface roughness by using a surface roughness tester,To observe the degree of enamel remineralization,SEM was observed at the initial,after acid erosion and after remineralization.Results: 1.After 7 days of acid erosion treatment,the surface microhardness of each samples decreased from the initial surface microhardness(P<0.05),and the roughness value increased from the initial(P<0.05),and there was no difference between groups.2.After 14 days of remineralization treatment,the surface microhardness of each group was higher than that after acid erosion,and there were differences between groups(P<0.05),nHA+CPCP-ACP group had the largest hardness value.3.After 14 days of mineralization treatment,the difference between groups was statistically significant(P<0.05),and the roughness value of nHA+CPP-ACP group was the minimum.4.By scanning electron microscopy,mineral deposits of different degrees were observed on the surface of each group,and more mineral deposits were observed in the nHA+CCP-ACP combined group.5.Under laser scanning confocal microscope,the infiltration of fluorescent dyes was different,and the nHA+CPP-ACP group was less than that of other samples.Conclusion: Dolfluorine,nHA and CPP-ACP can promote the remineralization of demineralization enamel caused by Coca-Cola,and the remineralization effect of nHA and CPP-ACP is more significant.