Oshiro Maki, Yamaguchi Kanako, Takamizawa Toshiki, Inage Hirohiko, Watanabe Takayuki, Irokawa Atsushi, Ando Susumu, Miyazaki Masashi
Department of Operative Dentistry, Nihon University School of Dentistry, Tokyo, Japan.
J Oral Sci. 2007 Jun;49(2):115-20. doi: 10.2334/josnusd.49.115.
Milk and milk products, such as cheese, have been shown to exhibit anticariogenic properties in human and animal models. CPP-ACP shows an anti-caries effect by suppressing demineralization, enhancing remineralization, or possibly a combination of both. The purpose of this study was to evaluate the effect of CPP-ACP paste on demineralization by observing the treated tooth surface using an FE-SEM. The specimens were prepared by cutting enamel and dentin of bovine teeth into blocks. A few specimens were stored in 0.1 M lactic acid buffer solution for 10 min and then in artificial saliva (negative control). The remaining specimens were stored in a 10 times-diluted solution of CPP-ACP paste or a placebo paste containing no CPP-ACP for 10 min, followed by 10 min immersion in a demineralizing solution (pH = 4.75, Ca) twice a day before storage in artificial saliva. After treatment of the specimens for 3, 7, 21 and 28 days, they were fixed in 2.5% glutaraldehyde in cacodylate buffer solution, dehydrated in ascending grades of tert-butyl alcohol, and then transferred to a critical-point dryer. The surfaces were coated with a thin film of Au in a vacuum evaporator, and were observed under field emission-scanning electron microscopy (FE-SEM). The SEM observations revealed different morphological features brought about by the various storage conditions. Demineralization of the enamel and dentin surfaces was more pronounced with the longer test period in the control and negative control specimens. On the other hand, enamel and dentin specimens treated with CPP-ACP paste revealed slight changes in their morphological features. From the morphological observations of the enamel and dentin surfaces, it could be considered that the CPP-ACP paste might prevent demineralization of the tooth structure.
牛奶及奶制品，如奶酪，已在人体和动物模型中显示出具有防龋特性。酪蛋白磷酸肽 - 无定形磷酸钙（CPP - ACP）通过抑制脱矿、增强再矿化或可能两者兼而有之来显示防龋效果。本研究的目的是通过使用场发射扫描电子显微镜（FE - SEM）观察处理后的牙齿表面，评估CPP - ACP糊剂对脱矿的影响。通过将牛牙的釉质和牙本质切成块状来制备标本。一些标本在0.1 M乳酸缓冲溶液中储存10分钟，然后置于人工唾液中（阴性对照）。其余标本在含CPP - ACP的10倍稀释的糊剂溶液或不含CPP - ACP的安慰剂糊剂中储存10分钟，然后每天两次在脱矿溶液（pH = 4.75，Ca）中浸泡10分钟，之后再储存于人工唾液中。在对标本进行3、7、21和28天的处理后，将它们固定在2.5%的戊二醛缓冲溶液中，用叔丁醇梯度脱水，然后转移至临界点干燥器中。在真空蒸发器中用金薄膜对表面进行镀膜，并在场发射扫描电子显微镜（FE - SEM）下观察。扫描电子显微镜观察揭示了各种储存条件所带来的不同形态特征。在对照和阴性对照标本中，随着测试时间延长，釉质和牙本质表面的脱矿更为明显。另一方面，用CPP - ACP糊剂处理的釉质和牙本质标本在形态特征上显示出轻微变化。从釉质和牙本质表面的形态观察来看，可以认为CPP - ACP糊剂可能会防止牙齿结构的脱矿。
