Studies on the Effect of Epigallocatechin Gallate-Carboxymethyl Chitosan Hydrogel on the Remineralization of Early Root Surface Caries

Objective: To observe in vitro the effect of epigallocatechin gallate-carboxymethyl chitosan hydrogel on the remineralization of early root surface caries. METHODS: Freshly extracted healthy bovine incisors were selected and prepared into dental bone blocks, and after establishing an artificial caries model, they were randomly divided into the epigallocatechin gallate-carboxymethyl chitosan (EGCG-CMCS) hydrogel group, the carboxymethyl chitosan (CMCS) hydrogel group, the epigallocatechin gallate solution (EGCG) group, the deionized water group, and the 2% NaF solution group, and each group was remineralized. The remineralization treatment was carried out; SEM was used to observe the surface morphology of the remineralized specimens, X-ray spectrometry was used to analyze the calcium-phosphorus ratio before and after remineralization of the specimen surfaces, a microhardness tester was used to detect the hardness value of the specimen surfaces, and a fluorescence microscope was used to detect the staining of the specimen slices. RESULTS: After remineralization treatment, scanning electron microscopy observation showed that spherical particles were deposited and flattened on the surface of the dentin in both the EGCG-CMCS hydrogel group and the 2% NaF group; the calcium-phosphorus mass ratio and atomic ratio of the dentin samples in the EGCG-CMCS hydrogel group and the dentin samples before demineralization were closest to each other, and there was no statistically significant difference between the two groups (P > 0.05); the microhardness results showed the hardness values of specimen sections stained via the 2% NaF and EGCG The microhardness results showed that those treated by 2% NaF and EGCG-CMCS hydrogel were better; the fluorescence intensity of the treated dental bone samples was the weakest in the EGCG-CMCS hydrogel group, followed by the 2% NaF group. Conclusion: Epigallocatechin gallate-carboxymethyl chitosan hydrogel has a good remineralization effect on early root surface caries and has the value of clinical application.