Mineral distributions in enamel after in vivo de- and remineralization

Plates of human enamel were demineralized under plaque in 18 participants. The subjects were randomly allocated to 3 groups consuming 0, 1 or 2 filled chocolate products (FCP) in between meals daily for periods of 4 weeks. Subsequently, the specimens were remineralized in vivo for 9 weeks, with or without the consumption of an FCP. The mineral distribution was assessed by means of microradiography. Special emphasis was placed on the type of mineral distribution. The results showed that: 1) significantly more enamel samples demineralized in vivo with a surface layer covering the lesion, when FCP's were eaten in between meals. The ranking of the number of samples with a surface layer was 0 FCP less than 1 FCP less than 2 FCP. 2) The amount of mineral lost during demineralization was not statistically different between 0 and 1 FCP. There is a difference between 0 and 2 FCP. 3) There was no difference in surface layer thickness or mineral content in the surface layer of 0, 1 or 2 FCP consumption in the demineralization experiment. 4) After 9 weeks a substantial remineralization occurred. There was no difference in remineralization between the 0 and 1 FCP group. 5) No difference in the percentage remineralization was found between mineral distributions with or without a surface layer.