False about enamel spindle is
**Core Concept**
Enamel spindles are small projections of enamel that extend from the surface of the enamel into the dentino-enamel junction (DEJ), a critical zone of the tooth structure where the enamel and dentin meet. The primary function of enamel spindles is to provide additional support to the enamel and to help maintain the integrity of the tooth structure.
**Why the Correct Answer is Right**
Enamel spindles are composed of highly mineralized enamel that is tightly attached to the dentin at the DEJ. The presence of enamel spindles helps to distribute the forces of mastication (chewing) and to prevent the formation of cracks and fissures in the enamel. The enamel spindles also play a role in the development and maintenance of the tooth structure, particularly in the formation of the DEJ.
**Why Each Wrong Option is Incorrect**
**Option A:** Enamel spindles are composed of dentin, not enamel. This statement is incorrect because enamel spindles are actually made up of highly mineralized enamel, not dentin.
**Option B:** Enamel spindles are found only on the occlusal surface of the tooth. This statement is incorrect because enamel spindles can be found on all surfaces of the tooth, not just the occlusal surface.
**Option C:** Enamel spindles are not essential for tooth development. This statement is incorrect because enamel spindles play a critical role in the development and maintenance of the tooth structure, particularly in the formation of the DEJ.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that enamel spindles are highly resistant to decay and wear because of their highly mineralized composition and tight attachment to the dentin at the DEJ. This makes them an important component of the tooth structure.
**Correct Answer: D. Enamel spindles are not essential for tooth development.**