Tooth decay is the destruction of tooth enamel by dental plaque that causes holes known as cavities. It strikes people of all ages, but is particularly prevalent in children ages 5 to 17 years, according to the U.S. Centers for Disease Control and Prevention.

A sticky film called dental plaque is the source of tooth decay. Plaque is made up of a combination of bacteria, acid, food particles and saliva. When a person consumes food, especially drinks high in sugars or carbohydrates, dental plaque builds up on the teeth and gradually erodes their structure.

Damage can occur in any part of the tooth that is exposed to plaque, from the crown at the top down to the softer body of the tooth (dentin) and the inner core of the pulp, which contains nerve fibers and blood vessels.

Patients with tooth decay do not usually experience any symptoms initially. However, if a cavity is not detected and begins to progress, it will often cause pain, particularly when eating sweet foods or when the tooth is exposed to hot or cold substances. Tooth pain may be the first physical symptom of tooth decay.

A dentist usually diagnoses tooth decay during a dental examination. Visual inspection and probing of the teeth with a special instrument can help indicate potential signs of damage. X-rays may be taken to confirm a diagnosis or to reveal hidden cavities.

Treatment for tooth decay varies depending on the nature and extent of the damage a patient experiences. In most cases, a dentist treats cavities by using a dental drill to remove the decayed material before filling the remaining space with dental amalgam or composite resin. More significant damage may require an artificial crown or root canal.

The single most important method of preventing tooth decay is to reduce the amount of plaque and bacteria in the mouth. Regular tooth brushing at least twice daily and flossing at least once daily is essential in decay prevention. In addition, patients should have their teeth professionally cleaned in a dentist’s office at least twice a year. People with certain conditions (e.g., diabetes) may require more frequent cleanings.