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Tooth Decay

Tooth decay is the process that results in a cavity (dental caries). If not treated, tooth decay can cause infection and loss of teeth.

A tooth has an outer layer (enamel), a middle layer (dentin), and a center (pulp). Tooth decay occurs when bacteria in the mouth make acids that eat away at a tooth. The more layers that decay, the worse the damage. If bacteria reach the pulp, the tooth likely will die. After a decayed tooth dies, a pus-filled pocket (abscess) may form in the bone at the end of the root.

Treatment for tooth decay depends on how severe it is. Holes (cavities) caused by mild tooth decay are repaired with fillings. More severe tooth decay requires repair with a crown or root canal treatment. In extreme cases a tooth will need to be removed (extracted).

The best way to prevent tooth decay is to practice good oral health habits such as daily brushing and flossing.

ByHealthwise Staff
Primary Medical ReviewerKathleen Romito, MD - Family Medicine
Specialist Medical ReviewerSteven K. Patterson, BS, DDS, MPH - Dentistry
Last RevisedJune 14, 2011

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