When the root was almost completely resorbed, a tooth would become loose.

当牙根几乎完全被吸收时，牙齿就会松动。

Sometimes these are broken teeth, but most of the time, they are teeth that have had their roots resorbed.

有时这些是断牙，但大多数时候，它们是根部被吸收的牙齿。

And as they grew, the roots of the older teeth were being dissolved and absorbed back into the jaw or resorbed.

随着它们的生长，较旧牙齿的根部被溶解并吸收回下巴或被吸收。