Exam 20: Enamel, Dentin, and Pulp

Young people are less susceptible to permanent pulpal damage than older people because with age the smaller pulp loses its reserve cells and is less able to resist trauma.

The asymmetrical bulging end shape within the ameloblasts is called the

The dental papilla has genetic control over tooth shape.

Which of the following are true of pulp stones (select all that apply)?

Each of the following is true of enamel EXCEPT one. Which one is the EXCEPTION?

Enamel, dentin, and pulp develop from the enamel organ. Enamel is derived from ectoderm whereas dentin and pulp are derived from mesoderm.

Enamel is generally yellowish in color but usually appears white because of the reflection of the color of the underlying dentin.

An enamel spindle is an ameloblastic process that becomes trapped in the dentin. Enamel spindles form in early development and are seen only histologically.

Each of the following accurately describes hypocalcified enamel EXCEPT one. Which one is the EXCEPTION?

The portion of the enamel rod that contains most of the fibrous organic substance is the

The size of pulp horns and chambers do not vary significantly with age.

For both primary and permanent teeth the process of tooth development is the same. Development occurs simultaneously in the anterior and posterior regions beginning at the cervical line and progresses toward the incisal/occlusal edges.

The multi-pointed cells that become dental papilla cells are called

During the maturation stage of calcification, an ameloblast produces enamel at what rate?

The dentin matrix creates a barrier between the dental papilla and the preameloblasts. With the resulting fluid shift and change in polarity, the preameloblast becomes an ameloblast.

During the mineralization stage of enamel rod calcification approximately half of the hydroxyapatite crystals are deposited because the remaining half are deposited during the maturation stage.

Pulp tissue consists of blood vessels, lymphatic vessels, nerves, fibroblasts, and collagen fibers. The nerves of the pulp are primarily sensory and transmit both pain and thermal sensations.

Each of the following is true of enamel lamellae EXCEPT one. Which one is the EXCEPTION?

The typical enamel rod is shaped wider at the top and more narrow at the bottom because the hydroxyapatite crystals in those portions differ in size.

Peripheral cells of the dental papilla are called ameloblasts.