If you experience unusual sensitivity to foods or beverages of a certain temperature (hot or cold), a localized pain near the gum line or even in your tooth, or if your teeth have changes in color then you are experiencing the warning signs of cavities and tooth decay. When left in a mouth that isn't flossed or brushed as often as it is needed, these materials can quickly break down and bacteria will go to work in the form of a colorless and sticky harmful substance best known as plaque. Plaque works with leftover foot particles to form harmful acids which destroy enamel the tooth's outer surface and then into the inner dentin material. If these cavities are not treated early, they can lead to more serious problems which require more complex dental treatment such as a root canal.