目的 观察再矿化制剂酪蛋白磷酸肽-无定形磷酸钙复合物（CPP-ACP）、含氟酪蛋白磷酸肽-无定形磷酸钙复合物（CPP-ACPF）、含氟磷酸三钙（TCP+F）和Duraphat 保护漆对酸蚀乳牙釉质表面硬度和表面形态的影响。方法 选取因滞留拔除的下颌乳中切牙制备离体牙釉质块（硬度值280～330 HV）试件50个，并随机分为对照组、CPP-ACP组、CPP-ACPF组、TCP+F组和Duraphat组。酸蚀处理所有试件(可口可乐，5次/d，5 min/次，共5 d)，酸蚀完成后，5组试件分别涂布去离子水（对照组）和CPP-ACP、CPP-ACPF、TCP+F、Duraphat进行再矿化处理，随后继续酸蚀处理5 d。采用显微硬度法测量处理前后各组试件的表面硬度（显微硬度值），扫描电子显微镜（扫描电镜）观察牙釉质表面形态的变化。结果 酸蚀处理前5组试件显微硬度值的差异无统计学意义（P>0.05）；酸蚀处理后各组试件的显微硬度值均显著低于酸蚀处理前（P<0.05），但各组间比较差异无统计学意义（P>0.05）；分组处理继续酸蚀5 d后，CPP-ACP组、CPP-ACPF组、TCP+F组和Duraphat组试件的显微硬度值均显著高于对照组（P<0.05），但4组间的差异无统计学意义（P>0.05）。扫描电镜观察发现，分组处理继续酸蚀5 d后，除对照组试件外，其余4组牙釉质块试件均可见矿物质沉积。结论 再矿化制剂CPP-ACP、CPP-ACPF、TCP+F和Duraphat均能有效抑制酸蚀乳牙釉质的持续脱矿。

Objective To observe the effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF), tri-calcium phosphate fluoride (TCP+F), and Duraphat fluoride varnish on surface hardness and surface morphology of eroded primary teeth enamel. Methods A total of 50 samples of retained mandibular primary central incisors (the hardness value was 280-330 HV) were collected and randomly divided into the control group, CPP-ACP group, CPP-ACPF group, TCP+F group, and Duraphat group. All samples were eroded by Coca-Cola for 5 min per time, 5 times a day for 5 d; remineralized by the deionized water (the control group), CPP-ACP, CPP-ACPF, TCP+F, and Duraphat; and then eroded for another 5 d. The surface hardness (microhardness value) of samples before and after treatment was measured by the microhardness tester. The morphological changes of enamel surface were observed by the scanning electron microscope. Results The differences of microhardness values of five groups before erosion treatment were not statistically significant (P>0.05). The microhardness values of each group after erosion treatment were significantly lower than those before erosion treatment (P<0.05), but the differences among groups were not statistically significant (P>0.05). After being eroded for another 5 d, the microhardness values of CPP-ACP group, CPP-ACPF group, TCP+F group, and Duraphat group were significantly higher than those of the control group (P<0.05), but the differences of four groups were not statistically significant (P>0.05). The mineral deposit was observed by the scanning electron microscope in samples of four groups after being eroded for

another 5 days, except samples of the control group. Conclusion Remineralization agents CPP-ACP, CPP-ACPF, TCP+F, and Duraphat fluoride varnish can effectively inhibit the continuous demineralization of eroded primary teeth enamel.