When acid constantly attacks the teeth, the hard outer shell of the tooth—the enamel—keeps losing minerals. A white spot, which signals early decay, may appear on a tooth, and the damage at this point can be reversed and enamel can repair itself. But if the tooth decay process isn’t reversed, enamel continues to get weaker as more minerals are lost and a cavity, which is permanent damage, forms and has to be fixed by a dentist.
You can prevent cavities. Minerals in our saliva, such as calcium and phosphate, along with the protective fluoride that we can get from fluoride toothpaste or a fluoride rinse or in some cases from fluoridated tap water, can repair minerals and protect them from acid damage. Your dentist may also apply a fluoride gel to teeth. The mineral fluoride prevents tooth decay from worsening, replaces minerals that have been lost, and reduces bacteria’s ability to turn sugar and starches into corrosive acid.