What is tooth decay?Dental caries, also known as tooth decay or cavity, is the progressive decay of tooth structure and can affect both the enamel (outer coating of the tooth) and the dentin layer of the tooth. It occurs when bacteria in your mouth produce acids that eat away at a tooth and if left untreated can cause pain, infection and tooth loss.
What causes tooth decay?Tooth decay occurs as a result of bacteria and lingering food debris on the teeth. As the bacteria feed on the sugars in the food, they convert them into acids. The bacteria, acid, food particles, and saliva then combine to form dental plaque -- a clear sticky substance that clings to the teeth.
The acids in plaque attack minerals in the teeth for 20 minutes or more after eating. These acids dissolve the tooth enamel, resulting in tiny openings called cavities. Once spots of enamel are worn away, the bacteria and acid can then reach the next layer of your teeth (dentin), which is softer and less resistant than the outer enamel.
Left unchecked, tooth decay continues on to the inner layer (pulp) which contains nerves and blood vessels. The pulp becomes swollen and irritated and the bone supporting the tooth may also become involved. When a cavity is this advanced, you may experience severe toothache, sensitivity and pain when biting or other symptoms.