Hi this is Dr. Neela Patel. One of the questions I get asked often by patients is, Doc what is a cavity any way? A cavity is actually caused by the acid that the bacteria in our mouth gives off. We have bacteria that lives in our mouths normally, this bacteria then eats what we leave behind. The sticky carbohydrates, the sugars that we eat and the acidic environment that we provide them by drinking sodas or coffee or even wine, create an environment for them flourish. Once these bacteria eat the plague that's left behind on our teeth these bacteria actually give off an acid. Acid is what is detrimental to your teeth, acid is what destroys the enamel and exposes the inner parts of the teeth that are very sensitive. That's what causes the pain.