【摘要】 目的观察缺锌对出生后大鼠牙釉质显微硬度及微观形态的影响,探讨缺锌对釉质发育的影响。方法将9只妊娠Wistar大鼠按体重随机均分为3组,分别为缺锌组(ZD组)、正常对照组(ZA组)、配对喂养组(PF组)。自母鼠分娩之日起,ZD组饲以低锌饲料,含锌量约为8mg/kg饲料,自由采食;ZA组饲以标准纯化饲料,含锌量为38mg/kg饲料,自由采食;PF组所食饲料与ZA组相同,且与ZD组各只鼠对饲。各组鼠均饮用超纯水。至仔鼠27日龄,仔鼠断乳,饮食饮水同原母鼠。处死38日龄仔鼠,取血,取上下颌前牙制备样本,进行血清锌浓度的测定,釉质显微硬度的测量及表面扫描电镜观察。结果 ZD组的血清锌浓度和釉质显微硬度均明显低于ZA组和PF组,差异具有统计学差异(P<0.05);而ZA组和PF组之间的差异不明显。扫描电镜示:ZD组的釉质表面不如ZA组和PF组平坦,且其釉质表面晶体颗粒的均匀性和致密度不及ZA组和PF组,而ZA组和PF组的微观形态差异不明显。结论饮食缺锌可降低大鼠牙釉质的显微硬度,并使釉质表面结构的均匀性和致密度受到影响。更多还原

【Abstract】 Objective To investigate the effect of zinc deficiency on rat enamel, the rat enamel microhardness was measured and the micromorphology of enamel surface was observed. Methods Nine pregnant Wistar rats were randomly divided into three groups according to body weight, they were zinc deficiency group(ZD group), the normal control group(ZA group)and pair-fed group(PF group), respectively. After parturition, the rats in ZD group were fed with low zinc fodder(8mg zinc/kg). Rats in ZA group were fed with standard purification fodder(38mg zinc/kg). And the rats in PF group were fed with the same fodder as ZA group, but pair fed to the rats in ZD group. The rats in all groups were given ultra-pure water. The offsprings were weaned and fed with the diet as well as the female rats until 27 days after parturition. And they were killed at postnatal day 38. Their blood and front teeth samples were collected respectivly.The serum zinc concentration and the rat enamel microhardness were tested, and the micromorphology of enamel surface was observed by scanning electron microscopy(SEM). Results Both the serum zinc concentration and the enamel microhardness in ZD group were significantly lower than those of ZA and PF group(P <0.05), while there were no significant differences between ZA and PF group. The enamel surface in ZD group was less flatter than that of the other two groups, and its uniformity and density of the crystal particles on enamel surface are inferior to the other two groups.No microstructure difference between ZA and PF group. Conclusion Dietary zinc deficiency could reduce the rat enamel microhardness, and affect the uniformity and density of enamel surface structure.更多还原