Nephew Da Bao grows really fast. I just learn that he has grown out two bottom teeth recently.

大宝长得很快，听说现在已经开始生出两颗下牙了。

youdao

Those pursuing perfection are advised to hide their gums, hold back on the bleach, cover the bottom teeth and set their lips at just the right angle.

所追求的完美微笑应该隐藏牙床，拒绝漂白牙齿，掩盖最里面的牙齿并且他们的嘴唇要达到合适的角度。

youdao

The molars are the largest teeth in the mouth and are also very strong - there are four at the top and four at the bottom.

臼齿是口腔内较大的牙齿，同样十分坚韧，分布于左右颊部后端，上下各四颗。

youdao

Ray looked out of the bedroom window, tilted his chin, opened his mouth just a touch, and tapped his fingernail against his bottom teeth.

NEWYORKER: Wasps

The crowns on his top teeth are a completely different colour from his own teeth in his bottom jaw.

ECONOMIST: Letters

Near the bottom of the New Scientist homepage are "sponsored links" that launch the curious to odd destinations including teeth whitening sites or German language sites that sell women's shoes--places that are probably only marginally interesting to most New Scientist readers.

FORBES: Magazine Article