In Vitro Assessment Of Sodium Fluoride Varnish On Early Root Caries Remineralization And Prevention

[Objective]The aim of the study was to observe and evaluate the effect of two different kinds of sodium fluoride varnishes on root caries remineralization and evaluate the effect of one sodium fluoride varnish on root caries prevention.[Methods]60 intergrated premolars and molars were sectioned.The teeth were randomly allocated into 6 groups.A 2mm*3mm windowing area was set on the mesial or distal of each tooth.All groups were used to establish artificial root caries models.Group CLP4 applied Clinpro XT Varnish after a 4-day demineralization,group DP4 applied Duraphat after a 4-day demineralization and group CLPpro applied Clinpro XT Varnish before demineralization were the experimental group.Group CHX4 applied Chlorhexidine after a 4-day demineralization and Group CLP6 applied Clinpro XT Varnish after a 6-day demineralization were the control groups with conditions.Group DW4 applied deionized water after a 4-day demineralization was the blank control group.Each group contain 10 teeth.5 groups were rinsed in lactic acid demineral solution of pH4.5.[CLP4],[DP4],[CHX4],[DW4],[CLPpro]were deminalized for 4 days,except for[CLP6]for 6 days.[CLPpro]was applied Clinpro XT Varnish before demineralization,then rinsed in lactic acid demineral solution for 4 days.After being applied reagents on,each group was subjected to a pH cycling protocol for 15 days to establish aritificial root caries models.The teeth were sectioned and stained by Goldner's trichrome.Light microscope was used to observe and measure the width of demineralization and remineralization layers.The treatment effects on the criterion variables were then evaluated.[Results]1.The Remineralization band width of[CLP4](10.832±3.746?m)was larger than[DP4](8.646±2.087?m).They were statistically significant(P<0.05).The Remineralization band width of[CLP4](31.355±3.082?m)was smaller than[DP4](36.250±2.853?m).They were statistically significant(P<0.05).the Remineralization band width and demineralization depth of[CHX4]and[DW4]were no statistically significant(P>0.05).2.The Remineralization band width of[CLP4]and[CLP6]were no statistically significant(P<0.05).The demineralization depth of[CLP4](31.355±3.082?m)was smaller than[CLP6](49.376±3.904?m).They were statistically significant(P<0.05).the Remineralization band width and demineralization depth of[CHX4]and[DW4]were no statistically significant(P>0.05).3.The Demineralization band width of[CLP4](31.355±3.082?m)was larger than[CLPpro](19.688±4.602?m).They were statistically significant(P<0.001).The demineralization depth of[DW4](54.063±6.102)was larger than[CLPpro](19.688±4.602?m).They were statistically significant(P<0.001).[Conclusion]Sodium fluoride varnish were significantly effective on the remineralization and prevention of root caries.With the same remineralization time,Clinpro XT varnish had larger width of remineralization layers than Duraphat.With the same remineralization time,Clinpro XT varnish formed similar depth of remineralization layer,even their lesion depths were different.