The Greeks, and then the Romans, improved the recipes for toothpaste by adding abrasives such as crushed bones and oyster shells, which were used to clean debris from teeth.

先是希腊人，然后是罗马人，将牙膏的配方加以改进。他们添加了一些磨料如碎骨和牡蛎壳，用来清除牙齿上的污垢。

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Later the bones help to keep your dogs teeth clean and white, and promote healthy gums.

而且的胸骨可以你们的狗狗的牙干净和白，是一个好好的健康香口胶。

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The Greeks, and then the Romans, improved the recipes for toothpaste by adding abrasives such as crushed bones and oyster shells, which were used to clean debris from teeth.

他们添加了一些磨料如碎骨和牡蛎壳，用来清除牙齿上的污垢。

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