After every meal, bacteria in your mouth produce acids that dissolve minerals from your enamel. Over time, this creates micro-lesions that develop into cavities. Regular toothpaste cleans the surface but doesn't replace lost minerals.

When enamel wears thin, it exposes the underlying dentin layer, which contains microscopic channels connected to your nerve. Cold water, hot coffee, or sweet foods trigger fluid movement in those channels — and that's what you feel as sharp, shooting pain.

Enamel that has been eroded or roughened traps stains more easily and reflects less light — making teeth look dull and yellow. Bleaching products can whiten temporarily, but they don't address the underlying enamel damage.