[The comparative study of the effect of silica and calcium carbonate based dentifrice on dentine abrasives in vitro].

ABSTRACT

PURPOSE: To evaluate the effect of Silica (SiO(2)) and Calcium Carbonate (CaCO(3)) based dentifrice on their dentine abrasives. METHODS: Microscope, environmental electron scanning electron microscope (SEM) and radioactive Dentine Abrasion (RDA) assay were used to quantitatively measure the wear of dentine. RESULTS: The mechanical brushing assay showed severe dentine abrasion with CaCO(3) based dentifrices. There were only minor scratches on the specimens brushed with SiO(2) dentifrices. Analysis of the thin section by SEM after exposure to dentifrices showed that NaF/SiO(2) produced significant remineralization whereas MFP/CaCO(3) system resulted in little remineralization. RDA values were 86.17 and 98.61 for SiO(2) based dentifrices and 222.85 and 253.84 for CaCO(3) based dentifrices, respectively. The morphology of the irregular shaped CaCO(3) with sharp points/edges further explained the brushing and RDA results. CONCLUSION: These results indicate that abrasive in dentifrice, e.g. CaCO(3), can cause severe abrasion of dentine in vitro.