Main body of dentin is formed by
Dentin is formed by odontoblasts, right? They're the cells responsible for producing the dentin matrix. But wait, there's also cementoblasts for cementum and ameloblasts for enamel. So, the main body of dentin has to be from odontoblasts. Let me double-check. The pulp of the tooth contains odontoblasts that lay down the dentin. The primary dentin is what forms the main body, and secondary dentin forms after root development. So the main body is definitely the primary dentin made by odontoblasts. The other options might be other cell types or structures. Let me make sure the answer is odontoblasts.
**Core Concept**
Dentin formation involves specialized cells that synthesize and mineralize the dentin matrix. The primary dentin constitutes the bulk of the tooth structure, excluding enamel and cementum.
**Why the Correct Answer is Right**
The main body of dentin is formed by **odontoblasts**, which are derived from neural crest cells. These cells secrete the organic matrix (predominantly collagen type I) and initiate mineralization. Primary dentin, formed during tooth development, constitutes the bulk of the dentin layer, while secondary dentin forms after root completion. Odontoblasts are unique to dentinogenesis, distinguishing them from ameloblasts (enamel) and cementoblasts (cementum).
**Why Each Wrong Option is Incorrect**
**Option A:** Ameloblasts produce enamel, not dentin.
**Option B:** Cementoblasts form cementum, the root covering.
**Option C:** Osteoblasts are involved in bone formation, not dental tissues.
**Clinical Pearl / High-Yield Fact**
Dentin hypersensitivity arises from exposed dentinal tubules, often due to enamel or cementum loss. Odontoblasts remain active post-eruption, forming tertiary dentin in response to injury.
**Correct Answer: C. Odontoblasts**