周后，冒出了两公厘宽的臼齿牙冠，具有牙髓腔、牙根的根尖、一层如骨骼般的象牙质，以及最基本的珐琅质。

Thirty weeks later two-millimeter-wide molar crowns emerged complete with pulp chambers root tips and bonelike layers of dentin and in a first enamel.

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周后，冒出了两公厘宽的臼齿牙冠，具有牙髓腔、牙根的根尖、一层如骨骼般的象牙质，以及最基本的珐琅质。

Thirty weeks later two-millimeter-wide molar crowns emerged complete with pulp chambers root tips and bonelike layers of dentin and in a first enamel.

youdao