It is the top gear tooth shape, only different last tooth is the fine teeth.

定装滚刀各齿齿形不同﹐只有最后一个齿是精切齿。

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The top front teeth are the ones which are most at risk from tooth decay.

上门齿是最容易受到腐蚀的牙齿。

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The top front teeth are the ones which are most at risk from tooth decay.

上门齿是最容易受到腐蚀的牙齿。

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