Experimental Study Of Flariesse Varnish Remineralization On Artificial Enamel Caries Lesions

Objective: Dental caries is still one of the most prevalent diseases affecting humans.It is a kind of chronic progressive disease that hard dental tissues are damaged predominantly by bacteria and other many factors.pathological changes of carious teeth involve enamel,dentin and cementum.Histopathologically,the basic changes are demineralization of inorganic mineral and decomposition of organic matter.Enamel in the outermost layer of dental crown will develop into a cavity by all kinds of the factors to cause caries.There are no nerves in enamel,so lesions can not be found in time by patients who never experience any discomforting.Finally this progressive disease lead to the loss of tooth tissues.Therefore,the primary problem is the treatment of early caries.As the times progress,oral medicine in the treatment of tooth decay is no longer constrained by "preventive extension" of the traditional treatment.With increased awareness for early detection and treatment,medical workers pay more attention on preventive medicine and hope to cure the disease by the painless minimally invasive treatment.Minimal Invasive(MI)Dentistry manages caries with a biological approach to promoting remineralization of etched enamel,rather than with a traditional(surgical)operative dentistry approach.This operation makes it easier to be accepted,especially the children patients' acceptance.Therefore,the developments of mineralization reagent are more and more.As one of remineralization materials,fluoride has been widely used in clinic,as well as the important reference standard for remineralization.Casein phosphopetides-amorphous calcium phosphate(CPP-ACP)has also been proven as a new type of remineralization matetial.Flairesse varnish is a new dental drug from DMG,used in the treatment of dentine hypersensitivity,prevention of dental caries and remineralization of initial enamel caries.This experiment analyze the effect of Flairesse varnish,to compare the effect of Duraphat and GC Tooth Mousse.The purpose is to guide the clinical medication.Methods: 41 premolars extracted for orthodontic reasons were selected,were visually examined to confirm the enamel developed well,one sample were observed under SEM randomly.The remaining 40 extracted teeth were randomly divided into four groups with ten teeth each.Group A: Flairesse varnish;Group B: Duraphat;Group C: GC Tooth Moussse,Group D: Distilled water.Each tooth with root removed were marked well and separated crown into buccal surface and tongue surface.Buccal enamel was preparaed into 5 mm x 5 mm x 2 mm enamel block,other tooth surfaces were painted with nail varnish except the experimental surface.Lingual enamel slabs were embedded in self-curing plastic,polished,and parallelled to the bottom surface.Four groups at the same time,soaked in the same amount of pH4.5 demineralization liquid for 5 days in an incubator at 37?,checked by the DIAGNOdent everyday.The demineralization liquid was updated everyday.A half of the buccal enamel surface was painted with nail varnish,the rest exposure surface of the samples were received drug treatment.According to 8:00?12:00?18:00,each group accepted drug treatment for 10 min,then put in the acidic buffer(pH 5.5)for 30 min,the other time between two time points put in artificial saliva.AB groups accepted once drug treatment during the whole experiment process,CD groups accepted drug treatment according each time point,pH remineralization solution in turn for 2 weeks cycle.Microhardness tester,scanning electron microscopy and laser scanning confocal microscope were used to observe each samples during experimental process.Results:1 Observation results of SEMA small amount of scratches were visible on enamel surface,with surface flat,structure compact well-distributed.Demineralized enamel showed increased porosity with fish-scale pattern and glaze column formed a centripetal demineralization.Group A: enamel surfaces coated compact layer,with no porosity.Group B: flocculent material deposited and a small amount of pores were visible on the surface.Group C: ranular deposits formed cap structure,oose pores were visible.Group D: granular material deposited "hollow" glaze column were visible on glaze surface.2 Observation results of LSCMFluorescent area and strength became big fllowing fluorescent deposited after demineralization,fluorescent area and strength became weaken after remineralization.The lesion depth and fluorescence intensity of each group reduced after the cycle.Group A was the most obvious group,followed by group B,group C,and group D.3 The results of KaVo DIAGNOdent(DD values)DD values carried out by variance analysis showed that: there was no significant difference between groups of lingual sample before demineralization(P>0.05).DD values of groups after demineralization had no significant differences(P>0.05).The difference values between before and after demineralization were no statistically significant(P>0.05).They proved mineralization degree of experimental samples was consistent.There was significant difference between before and after demineralization treatment group analysised by T test(P<0.05).DD values after demineralization were significantly greater than them before demineralization.This proved liquid of demineralization could increase DD values.4 The resultes of microhardness(HV)The microhardness of four groups after demineralization was analysis by One Way-ANOVO: The microhardness were no statistical difference between four groups(P>0.05).Paired t test used to compare hardness of intra-group between before and after of two stages in experiment showed that in four groups,there were all statistically significant differences(P>0.05).The variation of microhardness of four groups was analysis by covariance: The hardness gain was significant different after remineralization(P<0.05).Group A was the most obvious group,followed by group B,group C,and group D(P<0.05).Conclusions:1 DIAGNOdent is sensitive enough to detect the degree of enamel demineralization.2 Acetic acid treament can signficantly reduce the enamel micarohardness and form the model of demineralization.3 Artificial saliva have the effect of remineralization,but the effect is weak.4 Flariesse varnish,Duraphat and GC tooth Mousse can promote enamel remineralization,Flariesse varnish is the best.