Effects of Isomalt on enamel de- and remineralization, a combined in vitro pH-cycling model and in situ study

Isomalt is a non-cariogenic sweetener, which is widely used in sugar-free candy and chewing gum. Little is known about the effects of Isomalt on de- and remineralization. Binding between calcium and Isomalt has been reported, which could affect the mineral balance. The objective of this study was to examine the effects of Isomalt on de- and remineralization of bovine enamel lesions, both in vitro and in situ. In in vitro study, subsurface enamel lesions were subjected to 3-weeks pH-cycling. Treatments were 5-min rinses with 10% Isomalt solutions daily and 10% Isomalt additions to re- or demineralizing solutions. Standard pH-cycling conditions were used with a 0.2 ppm fluoride background during the remineralization phase. In in situ study, subsurface lesions were exposed 2 months in vivo and brushed three times daily with 10% Isomalt containing toothpaste. Treatment effects were assessed by chemical analysis of the solutions (in vitro) and transversal microradiography (in vitro and in situ). In in vitro study, while 5-min rinses with 10% Isomalt gave slightly increased remineralization, continuous presence of 10% Isomalt (in re- or demineralizing solutions) inhibited both de- and/or remineralization. This lead to significantly smaller overall mineral loss when Isomalt was added during demineralization. In in situ study, remineralization enhancement during short Isomalt treatments was confirmed. Isomalt had a positive effect on the de/remineralization balance when given under conditions relevant to practical use.