Overview
Cavities are permanently damaged areas in the hard surface of your teeth that develop into tiny openings or holes. Cavities, also called tooth decay or caries, are caused by a combination of factors, including bacteria in your mouth, frequent snacking, sipping sugary drinks and not cleaning your teeth well.
Cavities and tooth decay are among the world’s most common health problems. They’re especially common in children, teenagers and older adults. But anyone who has teeth can get cavities, including infants.
If cavities aren’t treated, they get larger and affect deeper layers of your teeth. They can lead to a severe toothache, infection and tooth loss. Regular dental visits and good brushing and flossing habits are your best protection against cavities and tooth decay.
Symptoms
The signs and symptoms of cavities vary, depending on their extent and location. When a cavity is just beginning, you may not have any symptoms at all. As the decay gets larger, it may cause signs and symptoms such as:
- Toothache, spontaneous pain or pain that occurs without any apparent cause
- Tooth sensitivity
- Mild to sharp pain when eating or drinking something sweet, hot or cold
- Visible holes or pits in your teeth
- Brown, black or white staining on any surface of a tooth
- Pain when you bite down
When to see a dentist
You may not be aware that a cavity is forming. That’s why it’s important to have regular dental checkups and cleanings, even when your mouth feels fine. However, if you experience a toothache or mouth pain, see your dentist as soon as possible.
Causes
Cavities are caused by tooth decay — a process that occurs over time. Here’s how tooth decay develops:
- Plaque forms. Dental plaque is a clear sticky film that coats your teeth. It’s due to eating a lot of sugars and starches and not cleaning your teeth well. When sugars and starches aren’t cleaned off your teeth, bacteria quickly begin feeding on them and form plaque. Plaque that stays on your teeth can harden under or above your gum line into tartar (calculus). Tartar makes plaque more difficult to remove and creates a shield for bacteria.
- Plaque attacks. The acids in plaque remove minerals in your tooth’s hard, outer enamel. This erosion causes tiny openings or holes in the enamel — the first stage of cavities. Once areas of enamel are worn away, the bacteria and acid can reach the next layer of your teeth, called dentin. This layer is softer than enamel and less resistant to acid. Dentin has tiny tubes that directly communicate with the nerve of the tooth causing sensitivity.
- Destruction continues. As tooth decay develops, the bacteria and acid continue their march through your teeth, moving next to the inner tooth material (pulp) that contains nerves and blood vessels. The pulp becomes swollen and irritated from the bacteria. Because there is no place for the swelling to expand inside of a tooth, the nerve becomes pressed, causing pain. Discomfort can even extend outside of the tooth root to the bone.