Effect of fluoride on remineralization of artificial enamel caries in pH 4.3 and pH 7.0 remineralizing solution

Abstract

Effect of fluoride on remineralization of artificial enamel caries in pH 4.3 and pH 7.0 remineralizing solution Sang-Chai SongDepartment of DentistryThe Graduate School, Yonsei University(Directed by Professor Chan-Young Lee)In many epidemiologic studies, the caries incidence becomes low in drinking water with fluoride and initial enamel caries has been disappeared by fluoride, and crystallographically fluoridated hydroxyapatite has much lower solubility than normal hydroxyapatite due to fluoride crystal’s stability and its growth mechanism.With this characteristic of fluoride, there have been many studies for remineralization of caries lesion; Margolis et al. explained the precipitation of fluoridated hydoxyapatite for remineralization using the degree of saturation physiologically.Although the remineralization occurs much more with increasing degree of saturation, it doesn’t occur to the inner portion completely. Therefore, there have been attempts of the remineralzation to the inner portion by lowering the degree of saturation on the surface zone in order to resolve this kind of problem.In many cases, there have been many applications to remineralize the caries with fluoride yet clear theoretical explanations or evidences are not enough.The objective of this experiment was to figure out how fluoride affects the remineralization of artificial enamel caries lesion with the comparison of the phase of the remineralization to the artificial enamel caries in terms of different fluoride concentrations in the remineralizing solutions with pH 4.3 and pH 7.0.The following experimental results were obtained after the calculation of the degree of density of the thin sections whose enamel was demineralized in the demineralizing solution and remineralization was observed under the polarizing microscope for eight days at maximum.1.The more fluoride concentration increased, the more the remineralization occurred in pH4.3 remineralizing solution. (group 1,2,4, p<0.05)2.The entire rate of remineralization increased in the pH 7.0 remineralizing solution. however; there was no significant difference in fluoride concentration.3.As fluoride concentration increased in pH 4.3 remineralizing solution, the rate of remineralization both on the surface zone and subsurface zone increased.4.As fluoride concentration increased in pH 7.0 remineralizing solution, the rate of remineralization on the surface zone exceeds that of on the subsurface zone. In conclusion, fluoride affected the remineralization of the enamel artificial caries more in pH 4.3 than in pH 7.0.