Is enamel or dentin more an efficient buffer for acids?

• A. Dentin
• B. Enamel
• C. Cementum
• D. Pulp

Answer: (A)

The main concept is buffering capacity in dental tissues, which depends on the presence of buffering agents and fluid pathways that can neutralize acids. Enamel is highly mineralized with very little organic matrix and almost no internal fluid flow, so it has almost no buffering ability; when acid hits enamel, the response is mainly mineral loss rather than neutralization. Dentin, on the other hand, contains organic components like collagen and a network of dentinal tubules filled with fluid that carries buffering ions such as bicarbonate. This setup allows acids that diffuse into dentin to be partially neutralized, slowing the drop in pH and delaying demineralization. Because of these buffering ions and the permeability of dentin, it acts as a more efficient buffer than enamel in acidic conditions.