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不同种类的牙齿有什么功用

由上而下可分成牙冠、牙颈和牙根。牙冠也就是牙齿露出来的部分,外表覆盖着一层比骨头还硬的法琅质,牙冠视察齿最容易发生蛀牙的部位。康朝星由内而外可分成法琅质、象牙质及牙髓腔,象牙质没有法琅质僵硬,但也有许多与骨头相同的成分,牙髓腔则是一种包覆着血管及神经末梢的软组织。

不同种类的牙齿有什么功用

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