中文摘要：

通过掺羟基磷灰石（HA）牙膏对早期龋模型进行处理，应用扫描电镜和显微硬度计对再矿化效果进行分析，同时将掺HA牙膏和空白牙膏分别配成不同质量浓度的牙膏悬液，分别加入0．2mg·L^-1的镉离子溶液中，静置24h后去上清液用电感藕合等离子发射光谱仪测定残余镉离子的量，比较2种牙膏对水溶液中镉离子的吸附情况。结果显示，处理1和2周时掺HA牙膏组釉质的显微硬度分别为253．87±5．66和291．90±10．37，而空白牙膏组则分别仅为199．73±7．11和200．07±9．84，有统计学意义（P〈0．05）；扫描电镜下可见HA处理对早期龋脱矿牙釉质再矿化作用明显；各质量浓度组的掺HA牙膏对镉离子的吸附率均高于空白牙膏。结果表明将HA掺入牙膏可提高其修复早期龋的作用，同时增强了对水中镉离子的吸附作用。

英文摘要：

Models of tooth with early stage caries were treated with suspension of toothpaste containing hydroxyapatite （HA）. The effect of re - mineralization of tooth enamel surface was assessed by scanning electron microscopy and microhardness value measurement. Cadmium ion solutions with initial mass concentration of 0. 2 mg · L-1 were mixed with toothpaste suspensions with and without addition of HA respectively and then been kept still for 24 h. The residual cadmium ion mass concentration of the supernatant was measured by inductively coupled plasma emission spectrometer and the adsorption effect of cadmium ion was calculated. Results showed that the toothpaste containing HA could significantly re -mineralize and improve the microhardness of artificial enamel caries. The Vicker＇s hardness values were 253.87 ± 5.66 and 291.90 ± 10.37 in HA group, higher than that of 199.73 ± 7. 11 and 200.07 ± 9. 84 in control group （ P 〈 0.05 ）. The adsorption rate of cadmium ion of toothpaste containing HA is higher than that of the control group.