单词tooth-powder
na.: 牙粉
网络: 粉状
牙粉
Coal powder, salt, rough tooth powder, etc when used for brushing lead to scratches in the outer layer of the teeth.
如果使用盐、粗牙粉等刷牙，会导致牙齿外壁划痕。
He says they actually use dental floss to slowly saw away at the metal, adding tooth powder to increase the friction.
但是犯人们总能找到办法弄到。现在他们用牙线慢慢钜金属，抹上牙粉增加摩擦力。