You need food, particularly sweet and sticky food, for the bacteria in your mouth to produce acids that will attack the tooth enamel (outer surface of the tooth).

你需要食物，特别是甜食和粘性食物，你口腔中的细菌就会利用它产酸并损害牙釉质（牙齿表面光亮的那一层）。

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Saliva helps protect teeth and gums from bacteria that cause cavities and gingivitis. So a perpetually dry mouth is more susceptible to tooth decay and gum disease.

唾液可以保护牙齿免受引发牙齿腔洞和牙龈炎的细菌感染，所以长期干燥的口腔更易患这两种疾病。

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That means the toothbrush handle should fit comfortably in your hand and the toothbrush head should feel comfortable in your mouth and be able to reach every tooth surface.

那就是说，牙刷柄应该合手，牙刷头应该合嘴并能刷到牙齿的每个面。

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"It's hand to mouth but we will fight tooth and nail to keep it going and to open on more evenings, " admits Jo Jones.

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Several of the book's 11 stories are set in Elk Tooth, a two-bit town of three bars and 80 residents, many with mouth-clogging names: Gilbert Wolfscale, Hard Winter Ulph, Wiregrass Cokendall.

ECONOMIST: New fiction