The Remineralization Effect of FN-CP, POs-Ca or CPP-ACP Contained in Commercially Available Chewing Gum on Initial Caries-like Enamel Lesion

Some types of chewing gum known to have a remineralization effect on teeth are recognized as "Food for Specified Health Uses" by the Ministry of Health, Labor and Welfare. This study analyzed the remineralization pattern using three different commercially available chewing gums, containing Gloiopeltis furcata, calcium hydrogen phosphate (FN-CP), and phosphoryl-oligosaccharide (POs-Ca), and casein phosphopeptide-stabilized calcium phosphate (CPP-ACP). Non-carious third molars extracted from humans were used. The enamel surface of the crown segment was coated with Sticky Wax (Kerr, USA) with a 3×4mm window. Firstly, these samples were demineralized in 0.01mol/l sodium acetate buffer (pH 4.0) at 50℃ for 2 days. Secondly, the other half of the area was remineralized through immersion in the solution at 37℃ for 2 weeks with agitation. The control group was immersed in remineralization solution (1.0mmol/l CaCl₂, 0.6mmol/l KH₂PO₄, and 0.1mol/l NaCl(pH7.3)) and the other tested groups were immersed in remineralization solutions containing three different materials as above described which were extracted from each gum separately. After the procedure of de- and remineralization, specimens were prepared for the transverse microradiography (TMR) procedure, which is the most popular method of evaluating de- and remineralization. New software for microradiography was used to calculate nine parameters analyzing remineralization pattern from the TMR images for analysis. A significant increase of ΔΔZ found in those three solutions indicated that they all have a remineralization effect in the subsurface lesions. In case of FN-CP solution, another eight parameters, ΔLd, ΔLBd, ΔLB, ΔSZ, ΔOSZ, ΔSA, ΔILB and ΔΔZ, indicated significant differences. It is suggested that FN-CP promotes remineralization mainly at the deep area of the subsurface lesion. In the case of POs-Ca solution, three parameters of ΔLB, ΔILB and ΔΔZ indicated significant differences, suggesting that POs-Ca promotes remineralization at the deep area of the subsurface lesion. In the case of CPP-ACP solution, significant differences of five parameters, ΔLB, ΔSZ, ΔSA, ΔILB, ΔΔZ, were observed, indicating that CPP-ACP promotes remineralization at the middle and deep area of the subsurface lesion. These results indicate that all three solutions promoted the remineralization effect in the initial caries-like enamel lesion, although with different patterns of it. Among these three solutions, FN-CP has the most effective pattern of remineralization on primary enamel caries.