Final answer:
The surface of a tooth that contacts the tooth in front of it in the dental arch is covered by enamel, which is the hardest substance in the body. Below the enamel is dentin, and the root is covered by cementum. These components, along with the periodontal ligament and gingivae, make up the tooth's structure.
Step-by-step explanation:
The surface of a tooth that normally contacts the tooth immediately anterior to it in the dental arch is covered by enamel. Enamel is the hardest material in the body and covers the visible outer surface of the tooth's crown. Beneath the enamel, the crown and the root of the tooth contain a layer of dentin, which is a bone-like tissue. The root is further covered by cementum, which, along with the periodontal ligament, anchors the tooth in the jaw bone. The crown is the part of the tooth that projects above the gum line, while the root is embedded within the maxilla (upper jaw) or mandible (lower jaw).
The anatomy of a tooth also includes an inner pulp cavity that runs through the crown down to the root canal. The pulp cavity contains loose connective tissue, nerves, and blood vessels. The teeth are held within the alveolar processes of the maxilla and mandible by the periodontal ligament and surrounded by gingivae (gums).