The upper tooth that was biting against the missing lower tooth will drop downward, because there's nothing below it to hold it in place.

原来与这颗牙拔掉上下咬合的上排的牙齿，因为在它底下没有牙齿承住它，会变的往下突出。

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To see how the brain responds to pain emanating from different teeth, the researchers used fMRI to monitor changes in activity when the upper tooth or the lower tooth was zapped.

为了分析大脑如何对不同牙齿的痛疼作出反应，研究人员利用功能磁共振成像监视上牙或下牙在受到脉冲刺激时的活动。

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And the data showed that people who reported tooth and gum disease had lower scores on tests that measured memory and cognition.

数据表明，那些患有牙齿和牙龈疾病的人在记忆力和认知力方面的测试分数也很低。

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To satisfy its sweet tooth, most years it imports some, at a price lower than the home-grown cane.

ECONOMIST: Antonio Fortich