Non-Invasive Infiltration Techniques Inhibit The Progression Of Enamel Caries Lesions And Mask The White Spot Lesions In Vitro

Background and Objectives：Non-invasive infiltration is a way of avoiding removal tooth structure treatment,covering the enamel white spot lesions and improving the appearance of the teethwith only one treatment. Meanwhile it can inhibit caries progression, as well as drawenamel caries to a simple, fast, effective, and non-invasive direction. This experimentwhich provides strong theoretical basis for the effective and lasting treatment of earlycaries, further explores the treatment effect of non-invasive infiltration on inhibitingprogress of caries, masking the white spot lesions, and the effect of a different degreeof demineralization of early caries, by systematic study of non-invasive penetrationtechnical treatment of early caries.Methods：Experiment I: Inhibition of early caries progression by non-invasive infiltration invitroThirty human premolars,freshly extracted,caries-free for orthodontic reasons,made into5mm×5mm×2mm size enamel.Prepared early caries specimens, whichwas divided into2groups with DIAGNOdentPen(DDPen).Group I: lowdemineralization group; Group II: high demineralization group. After non-invasiveinfiltration, each group of samples is divided into two subgroups: group a, in turnplaced in artificial saliva and cariogenic solution12h (15d) in turn; group b, placedin artificial saliva (15d). With observing the depth of penetration of Ia, Ib, IIa, IIb bylaser scanning confocal microscope, we can compare effect between lowdemineralization and high demineralization inhibiton of early caries progression bynon-invasive infiltration.Experiment II: Masking of enamel white spot lesions progression by non-invasiveinfiltration in vitroForty human premolars,freshly extracted,caries-free for orthodontic reasons,made into5mm×5mm×2mm size enamel.Prepared early caries specimens,which was divided into2group with DIAGNOdentPen(DDPen).Group I: lowdemineralization group; Group II: high demineralization group. All specimens areplaced in artificial saliva and cariogenic solution12h (15d) in turn. The assessment of40samples' color are performed by a spectrophotometer in four times: before theproduction of artificial caries;after the production of artificial caries;afternon-invasive infiltration;and after a new acid challenge. All for comparing two sets oflow demineralization and high demineralization effect of masking the enamel whitespot lesions by non-invasive infiltration.Results：1.In the low demineralization group, sample penetration depth in the salivaenvironment and demineralization environment (group Ia and group Ib)aredifferences(P=0.000<0.01).In the high demineralization group, Sample penetrationdepth in the saliva environment and demineralization environment (group IIa andgroup IIb) have no difference(P=0.015>0.01).In the saliva environment, Samplepenetration depth in the low demineralization group and high demineralization group(group Ib and group IIb)have no difference(P=1.000>0.01).In the demineralizationenvironment, Sample penetration depth in the low demineralization group and highdemineralization group (group Ia and group IIa) are differences(P=0.004<0.01).2. The statistical results shows that ΔE1(the chromatic difference value betweenafter non-invasive infiltration and before the production of artificial caries) andΔE2(the chromatic difference value between after a new acid challenge and beforethe production of artificial caries) are less than1.5NBS, which cannot be sensed byhuman eyes..The statistical results shows that ΔE3(the chromatic difference valuebetween after non-invasive infiltration and after the production of artificial caries)and ΔE4(the chromatic difference value between after a new acid challenge and afterthe production of artificial caries) are greater than1.5NBS, which can be sensed byhuman eyes.3. Comparing four chromatic difference value of low demineralization and highdemineralization, we get the result that ΔE1,ΔE2,ΔE3,ΔE4between the two groupswas not statistically significant(P>0.05). Conclusion：1.The early caries by non-invasive infiltration in demineralization environmentcan be antagonist to demineralization. And antagonistic of high demineralizationgroup are better than the low demineralization group.2.Non-invasive infiltration has an excellent ability of masking white spot lesionsno matter in the high demineralization group, the low demineralization group, or aftera new acid challenge. Meanwhile, the colour is stabilization.