Tooth decay is the destruction of tooth structure and can affect both the enamel (the outer coating of the tooth) and the dentin layer of the tooth. Tooth decay occurs when foods containing carbohydrates (sugars and starches), such as breads, cereals, milk, soda, fruits, cakes, or candy are left on the teeth. Bacteria that live in the mouth digest these foods, turning them into acids. The bacteria, acid, food debris, and saliva combine to form plaque, which clings to the teeth. The acids in plaque dissolve the enamel surface of the teeth, creating holes in the teeth called cavities.


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