But dentists said some of the methods can erode the enamel covering of the teeth making them appear darker rather than whiter.

但牙医提醒说，有些方法可能会损伤覆盖在牙齿上的牙釉质，反而让牙齿显得更黑。

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Wang Na was born with no upper jaw bone or teeth, making eating and speaking very difficult.

王娜天生就没有上颌骨和牙齿，这使得她吃东西和讲话都很吃力。

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The faster the pulse repetition rate, the wider the spacing between the teeth, making each individual tooth easier to identify.

脉冲重复率越高，齿间距越大，各个齿之间也越容易分辨。

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But when Mr Kadyrov reaches out to pat it, the cub growls and bares its teeth, making sure the message is clear.

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Some patients tell me that they are so connected that even before brushing their teeth or making coffee, they will roll over to check their phone- when a more appropriate choice may be to spend a few extra minutes in bed with their loved ones.

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Early forms of teeth whitening include using the herb elecampane (Inula helenium) to scrub the teeth and taking sage leaves and making a powder of them and salt.

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