Cavity is decay in the tooth. It is primarily caused by acids in mouth. Plaque is the sticky film of food and bacteria that forms constantly on your teeth. It's hard to see plaque without staining it. If you don't remove the plaque every day, these bacteria produce acid that which eventually create a hole in your tooth. That is what a cavity is a small hole in the outer layer of your tooth.
Finding cavities is sometimes easy, but sometimes it is more difficult. For hard-to-find cavities, a dental explorer and X-rays are used. Cavities show up as dark spots. It's far better to catch and restore decayed areas while they're still small and in the enamel layer of the tooth. Once they're in the softer dentin layer, they really grow quickly. If they make it to the pulp chamber, we have a whole new set of problems and a different treatment to discuss - root canal therapy.
