Preoperative etching improved the effect of the varnish in severe discolored fluorine teeth.

对于重度着色氟牙症，涂膜前进行酸蚀，可明显加强涂膜的漂白作用。

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Any accidental release of fluorine could also be an issue: fluorine is a toxic and corrosive gas and, at high concentrations, can retard plant growth and damage teeth and bones.

氟气的任一次意外泄漏也都可能造成问题。氟气是一种有毒的腐蚀性气体，而且，在高浓度时，能阻碍植物生长并，损伤牙齿和骨骼。

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