Final answer:
When viewed from the labial surface, the tooth's structure includes a crown with an enamel surface, dentin layer, and pulp cavity, and a root covered by cementum, housing the root canal, all supported by the surrounding gingivae.
Step-by-step explanation:
Anatomy of a Tooth
When viewing from the labial surface or buccal aspect, the crown of the tooth, which is visible above the gum line, is typically divided into the outer enamel layer, the dentin layer beneath it, and the innermost pulp cavity that contains nerves and blood vessels. Enamel is the hardest substance in the body, providing protection to the tooth. The dentin covers the pulp cavity in both the crown and the root, providing a secondary layer of hardness and structural support.
The root of the tooth, which extends into the maxilla or mandible, has dentin covered by cementum, a hard layer that, in conjunction with the periodontal ligament, helps to anchor the tooth securely in the jaw. Within the root, the dentin surrounds the root canal, which is a continuation of the pulp cavity, housing vital connective tissue, nerves, and blood vessels. The soft tissues called gingivae (gums) around the crown of the tooth help to protect the tooth and maintain oral health.
The crown of a tooth, as seen from the labial surface, displays an outer layer of enamel, underlying dentin, and the inner pulp cavity, while the root is covered by cementum over dentin surrounding the root canal, all supported by the gingivae. These structures work together to allow teeth to function properly in biting, chewing, and overall oral health.