Remineralization occurs when acid is buffered by which oral fluid?

• A. Saliva
• B. Sweat
• C. Serum
• D. Tears

Answer: (A)

Remineralization happens when acids in the mouth are neutralized and minerals are made available to redeposit into early enamel lesions. Saliva is the oral fluid that does this most effectively. Its buffering components, mainly bicarbonate and phosphate, raise pH after acid exposure, while it also supplies calcium and phosphate ions needed to rebuild hydroxyapatite crystals. Fluoride in saliva can further enhance this process by helping form more stable mineral phases like fluorapatite.

Sweat, serum, and tears don’t bathe the tooth surfaces in the same way saliva does, and they don’t deliver minerals to the enamel in the oral environment. Thus, they don’t play the primary role in buffering acid for remineralization in the mouth.