Tooth
Teeth
noun
The kanji and the word are exactly the same. That means they share meanings as well.
The reading that you learned with the kanji is the same as this one. HA! Take that, kanji.
七本目の歯が生えてきました。
Her seventh tooth came in.
タバコのすいすぎで歯が黄色くなってしまった。
I smoked so much that my teeth are yellow now.
電動歯ブラシを買うことを考えているんだが、どれも値段が高いんだよね。
I’m thinking about buying one of those electric toothbrushes, but they’re so expensive.