Parents toss a lost bottom tooth up to the rooftops, so that the new tooth will grow upwards, too.

父母将孩子下牙床的掉牙扔上屋顶，这样新牙才会向上长。

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The converging lower portion of each tooth follows the convergence of the bottom portions of the sidewalls.

每个齿的收敛下 部遵循侧壁底部的收敛性。

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They cover the bottom part of the crown of the tooth and extend down to the cheek.

它们包括底部的一部分，官方的牙齿和延伸到脸颊。

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The tooth needs to be drilled into, right down to the bottom of the nerve-carrying canal that runs through the root.

ECONOMIST: Using a plasma torch to clean your teeth

This is partly because farming or buying hops puts pressure on the bottom line, but also because many American drinkers weaned on soft drinks have never developed the Old World tooth for bitterness.

FORBES: Czech Mate