Which cells are primarily responsible for enamel and dentin formation?

• A. Ameloblasts for enamel; odontoblasts for dentin
• B. Odontoblasts for enamel; ameloblasts for dentin
• C. Cementoblasts for enamel; fibroblasts for dentin
• D. Fibroblasts for enamel; cementoblasts for dentin

Answer: (A)

Enamel and dentin come from different cell types during tooth development. Enamel is formed by ameloblasts, which come from the inner enamel epithelium and secrete the enamel matrix that mineralizes into the hard outer layer of the crown. Dentin is formed by odontoblasts, derived from the dental papilla, which line the pulp–dentin border and lay down predentin that becomes dentin. Cementoblasts create cementum on the root, and fibroblasts in the periodontal tissues handle connective tissue aspects, but they do not form enamel or dentin. So recognizing that enamel is produced by ameloblasts and dentin by odontoblasts explains why this pairing is correct.