The surface of our teeth is covered with a layer of enamel, which is transparent or translucent, and the deep layer is dentin, which is light yellow. The color of healthy teeth is deep dentin, which is pale yellow through enamel.
Due to various reasons, such as drinking tea and smoking for a long time, or diseases such as pulp necrosis, tetracycline teeth and fluorosis, many people's teeth are yellow, black or dull. In medicine, this kind of tooth is commonly known as colored tooth, which affects people's daily life and physical and mental health.
Although there are many kinds of traditional whitening toothpastes, their whitening ingredients are almost the same except for their different taste and efficacy. For the sake of safety and hygiene, the content of oxidant in whitening toothpaste is very low, so the whitening effect is generally not obvious.
In addition, whitening toothpaste can only remove a very small amount of stains and exogenous pigments on the tooth surface, and basically has no effect on teeth with endogenous stains such as tetracycline teeth and dental fluorosis, so it is basically impossible to whiten teeth simply by toothpaste.
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/health.people.com.cn/n1/2016/01471-2809165438.html "target =" _ People.com-There are four kinds of tea drinking.