Every day our teeth are stressed by the consumption of acidic foods. The acids and bacteria attack the enamel, gradually breaking it down and making microscopic cracks. The yellowish dentin under the enamel glistens through the damaged enamel surface and leaves your teeth looking dull, lackluster, and yellowish. The open tubules in the dentin are no longer protected. The result can be pain sensitivity to external stimuli, such as cold or hot.