Abstract
The objectives of this study were to study the remineralization effects on initial caries enamel lesions of xylitol chewing gum containing Gloiopeltis furcata extract (of which funoran is a main component)and calcium hydrogenphosphate (CaHPO4⋅2H2O) and of xylitol chewing gum containing phosphoryl-oligosaccharide calcium and to make comparative evaluations of the two.
Initial caries-like enamel lesions were prepared artificially by demineralizing human enamel blocks with a 0.01 M acetate buffer (pH 4.0) for 2 days at 50°C. In vitro investigation was performed by immersing these enamel blocks for 2 weeks at 37°C in a remineralizing solution (1.0 mM CaCl2,0.6 mM KH2PO4 and 100 mM NaCl; pH 7.3 with KOH) containing extracts from each chewing gum. These enamel specimens were dehydrated and embedded in polyester resin, then prepared as enamel sections 100μm in thickness. Contact microradiographs (CMR) obtained from the ground sections were observed under an optical microscope. Remineralization degrees were calculated with a computer image analyzer. Remineralization rate(%) was calculated by assigning a value of 0% to initial caries-like enamel and a value of 100% to intact enamel. Student's t-test was used to analyze the degree of remineralization of each chewing gum.
The results were as follows:
Xylitol chewing gum containing Gloiopeltis furcata extract and calcium hydrogenphosphate dramatically enhanced remineralization throughout all layers in initial caries-like enamel lesions, whereas xylitol chewing gum containing phosphoryl-oligosaccharide calcium produced little remineralized. The remineralization rate of xylitol chewing gum containing Gloiopeltis furcata extract and calcium hydrogenphosphate was 45.5%; that of xylitol chewing gum containing phosphoryl-oligosaccharide calcium was 23.7%. The remineralization rate of xylitol chewing gum containing Gloiopeltis furcata extract and calcium hydrogenphosphate was approximately 1.9 times that of xylitol chewing gum containing phosphoryl-oligosaccharide calcium (p< 0.01).
These findings clearly show that xylitol chewing gum containing Gloiopeltis furcata extract and calcium hydrogenphosphate remineralizes initial caries-like enamel lesions more effectively than xylitol chewing gum containing phosphoryl-oligosaccharide calcium.
