Use your thumbs and forefingers to gently pull the floss from the gumline to the top of the tooth to scrape off plaque.

用拇指和食指沿着齿龈向牙冠方向缓和地拉扯牙线，以去除牙菌斑。

youdao

First, I'll make a small opening in the top (crown) of the tooth to expose the infected pulp..

首先，我要在牙齿的顶端(牙冠)开一个口，使受感染的牙髓暴露出来。

youdao

Due to the above mentioned defects, early fatigue peeling occurs under the condition of overly contact stress at the top of the tooth caused by abnormal contact at the tooth surface.

因此，在齿面非正常接触导致齿顶接触应力过大的情况下，该齿轮发生了早期疲劳剥落。

youdao

You should always introduce the floss at the top of the tooth, in the gum line, and bring it down, then remove it and find an unused length for the next tooth.

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