Healthy tooth structure

Solution: The structure of teeth is shown in the following figure:

(1) Comparing the two pictures, we can see that the name of the label is dental pulp.

(2) Dentin is the main component of teeth.

(3) The root is covered by cementum.

(4) There are abundant nerves in dental pulp. If you don't pay attention to oral hygiene for a long time, bacteria in the mouth will turn sugar into acid, corrode enamel and dentin, and form tooth decay. When tooth decay goes deep into the pulp cavity, it will cause toothache.

So the answer is: (1) dental pulp; (2) Dentin; (3) cementum; (4) enamel; Dentin.