Final answer:
The section of the tooth beneath the enamel on the crown is called the dentin, a bone-like tissue critical for the structural integrity of the tooth. Dentin protects the inner pulp cavity, which contains the pulp with blood vessels and nerves, and in the root, it is covered by cementum.
Step-by-step explanation:
The section of the tooth beneath the enamel on the crown of the tooth is the dentin. Dentin is a bone-like tissue that provides an additional layer of protection under the enamel. Beneath the dentin in the crown is the pulp cavity which houses the pulp, containing blood vessels, lymphatics, connective tissue, and nerves. In the root, the dentin is covered by cementum, which helps anchor the tooth in the jawbone via the periodontal ligament. The surrounding soft tissues are known as the gingiva or gums.
Dentin is immediately deep to the enamel in the crown, or the cementum in the root, and is crucial for the structural integrity of the tooth. When looking at a cross-section of a tooth, one can see the close relationship between the enamel, dentin, and pulp. The pulp chamber is at the top of the tooth, leading down to the pulp canal, or root canal, located in the root.