Wear behavior of early carious enamel before and after remineralization

The purpose of the research was to evaluate the effect of remineralization treatment on the wear behavior of human early carious enamel. The degree of remineralization was observed with polarized light microscope and microhardness tester. Then the tribological properties of all the specimens were investigated by a CSEM nano-stratch tester system. The results showed that the hardness and density of carious enamel increased obviously, and the friction coefficient became higher after remineralization. It was easier to form cracks and debris on the remineralized enamel. It was concluded that the most effective remineralization agent (fluoride) in clinic could decrease the wear resistance of early carious enamel. There was no direct relationship between the content of minerals and the wear resistance of early carious enamel. The wear resistance of enamel could not be improved veritably by increasing the hardness. The main damage mechanisms of early carious enamel were the plastic deformation and adhesive wear while those of remineralized one were the combination of brittle cracks, plastic deformation and brittle delamination. New technique of remineralization is urgently needed clinically to improve the wear resistance.