Attention should be paid to brushing their teeth the right way: down the teeth brush verticalbrush outside good brush inside.

刷牙要注意正确的方法：顺着牙，竖着刷，刷完里面再刷外面。

youdao

Misalignment of teeth between the upper and lower jaws can grind down the teeth and cause problems in chewing. Elsewhere, it is a cosmetic problem.

下颚间的牙齿咬合不正会磨损牙齿并造成咀嚼问题，此外，也会造成外表美观的问题。

youdao

Pipe smokers sometimes wear down the tips of their teeth where they grip their pipes.

抽烟斗的人用牙齿咬住烟斗，有时会把牙齿尖磨平。

《柯林斯英汉双解大词典》

As he once told the Washington Post: "When I came down I hurt my teeth in the net."

VOA: special.2010.07.05

Dr Swenson lives with the Lakashi tribe a joyful people whose women can reproduce well into old age thanks to a magical substance they ingest by ritually scraping their teeth down the trunks of a tree.

ECONOMIST: The call of the Amazon

And enough carbon dioxide emissions to spur the anti-coal crew to gnash their teeth all the way down to the gums.

FORBES: Peabody Earnings Up, Coal Supercycle Just Beginning

Liverpool Crown Court heard that the dog's teeth had been filed down and it did not break the skin on her leg, but she was left with a bruise.

BBC: NEWS | UK | England | Merseyside | Man jailed over bull dog attack