球形二氧化硅和碳酸钙2种磨擦剂牙膏对牙本质影响的体外对比研究

目的：评价球形二氧化硅(SiO2)和碳酸钙(CaCO3)磨擦剂牙膏对牙本质的影响。方法：采用光镜、扫描电镜和放射活性方法检测牙本质磨损(RDA)，观察SiO2和CaCO3磨擦剂牙膏体外对牙本质表面磨损的影响，以及对牙本质的氟吸收量和牙本质再矿化的影响。结果：使用CaCO3磨擦剂牙膏刷牙造成了牙本质的明显磨损；SiO2牙膏的RDA值分别是98．61和86．17，而CaCO3牙膏的RDA值分别是222．85和253．84；相应也观测到CaCO3磨擦剂尖锐的形态；CaCO3牙膏牙本质的氟吸收量为7．28，SiO2牙本质的氟吸收量为21．65；扫描电镜观察证明，SiO2能明显促进牙本质的再矿化。结论：在体外试验中，CaCO3牙膏较SiO2牙膏更易造成牙本质的磨损。

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

PURPOSE: To evaluate the effect of Silica (SiO2) and Calcium Carbonate (CaCO3) 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 CaCO3 based dentifrices. There were only minor scratches on the specimens brushed with SiO2 dentifrices. Analysis of the thin section by SEM after exposure to dentifrices showed that NaF/SiO2 produced significant remineralization whereas MFP/CaCO3 system resulted in little remineralization. RDA values were 86.17 and 98.61 for SiO2 based dentifrices and 222.85 and 253.84 for CaCO3 based dentifrices, respectively. The morphology of the irregular shaped CaCO3 with sharp points/edges further explained the brushing and RDA results. CONCLUSION: These results indicate that abrasive in dentifrice, e.g. CaCO3, can cause severe abrasion of dentine in vitro.