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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Next time you're brushing your teeth, smear a bit of toothpaste on the bathroom mirror and wipe it dry.

下次你要刷牙的时候，往浴室的镜子上涂一点牙膏并将其擦干。

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Hard dry food is really good for my teeth. it can help to remove the residue of food.

比较有硬度的干粮是对我的牙齿很好的食物，可以帮助清除牙垢。

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An ingenious new laser called Waterlase adds to that the ability to cut through dry teeth and bone by casting a cloud of hot water vapor around the laser's cutting point, a couple of millimeters from the tooth.

FORBES: Magazine Article