有人认为“孩子的乳牙反正要换,无需防护”,忽视了对孩子乳牙的保护,这是不对的。一个小孩有二十颗乳牙,全部换成恒牙要到十二、三岁。乳牙是恒牙的基础,孩子三岁时,每个乳牙的下面已存在一个恒牙的牙胚。若乳牙有龋洞,就可能累及牙根,感染恒牙的牙胚,恒牙就长不好。 Some people think that “children’s deciduous teeth should be changed anyway, without protection,” neglect of the protection of children’s deciduous teeth, which is wrong. A child has twenty deciduous teeth, all replaced by permanent teeth to twelve or three years old. Deciduous teeth are the foundation of permanent teeth. When a child is three years old, there is a permanent tooth germ under each deciduous tooth. If the deciduous teeth have cavities, it may be involved in the root, the permanent tooth infection of tooth germs, permanent teeth is not good.