Dental Assistant Practice Exam

What structure connects the anatomical crown and the root of the tooth?

1. Apical foramen

2. Cemento-Enamel Junction

3. Dentinal tubules

4. Clinical crown

The correct answer is: Cemento-Enamel Junction

The structure that connects the anatomical crown and the root of the tooth is the Cemento-Enamel Junction (CEJ). The CEJ serves as the boundary between the enamel, which covers the anatomical crown, and the cementum, which covers the root of the tooth. This junction is significant as it reflects the transition from the enamel, a hard protective layer, to the softer cementum that helps anchor the tooth to the jawbone through the periodontal ligament. Understanding the CEJ is critical in various dental procedures and examinations, as damage or disease in this area can lead to issues such as sensitivity or periodontal disease. The apical foramen serves a different purpose as it is the opening at the tip of the tooth root where nerves and blood vessels enter; it does not connect the crown and root. Dentinal tubules are microscopic channels within the dentin, and the clinical crown refers to that portion of the tooth visible above the gum line, neither of which pertains to the connection between the anatomical crown and the root.