A tooth “cavity”, also called tooth decay, is a breakdown in the tooth structure. Acids break down the hard enamel structure of our teeth. This process is called demineralization of the enamel. When this demineralization extends through the enamel into the second layer of our teeth, called the dentin, it is diagnosed as a “cavity”.
What is the source of this acid that causes cavities? We have certain types of bacteria in our mouth that breakdown any carbohydrate or sugar into acids. Any type of acidic food or beverage has the same effect. Lemonade, diet soda, and fruit are examples of acidic foods and beverages.
How do we fight this process? Fluoride helps to remineralize the enamel. A very early cavity that has not extended completely through the enamel can often be arrested, or stopped, by using fluoride to remineralize the it. But when the cavity had reached the dentin, it cannot be stopped by fluoride and must be treated with a filling or another type of restoration.
Whenever you finish eating or drinking anything other than water, it is best to brush and floss to remove any particles that can remain stuck to your teeth and cause cavities. At the very least, swish your mouth with water, which will decrease the amount of food and acidic substances in your mouth.
As always, it is highly recommended to see your dentist regularly so cavities can be diagnosed and treated when they are small. If you wait until it hurts, the cavity is far advanced and will require more extensive treatment, if the tooth is even savable.