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Home > Health Library > Tooth Decay
Tooth decay is damage that occurs when germs (bacteria) in your mouth make acids that eat away at a tooth. It can lead to a hole in the tooth, called a cavity. If not treated, tooth decay can cause pain, infection, and tooth loss.
A tooth has three layers.
The more layers that are affected by decay, the worse the damage.
Bacteria and food can cause tooth decay. A clear, sticky substance called plaque is always forming on your teeth and gums. Plaque contains bacteria that feed on the sugars in the food you eat.
As the bacteria feed, they make acids. The acids attack the teeth for 20 minutes or more after you eat. Over time, these acids destroy tooth enamel, causing tooth decay.
Things that make you more likely to have tooth decay include:
Children, whose teeth are still growing, are more likely than adults to have tooth decay. This is because the minerals in new teeth are not very strong and are easier for acids to eat away.
Even babies can be at risk for tooth decay. Babies who are put to bed with a bottle can get "bottle mouth"—tooth decay caused by the sugar in milk, formula, or juice. Babies aren't born with decay-causing bacteria in their mouths. But they can get bacteria from adults who share spoons, forks, or other utensils with them.
Tooth decay usually doesn't cause symptoms until you have a cavity or an infected tooth. When this happens, you may have:
If you have a toothache, see a dentist. Sometimes the pain will go away for a while, but the tooth decay will keep growing. If you don't get treatment, your cavities could get worse and your tooth could die.
To diagnose tooth decay, your dentist will:
The best treatment for tooth decay depends on how severe it is. If tooth decay is caught early, before a cavity forms, you may be able to stop it by brushing with fluoride toothpaste or getting fluoride treatments. That's one good reason to see your dentist on a regular basis.
If the decay has eaten through the enamel, you may need one or more treatments, such as:
If you have pain and swelling, you can take steps at home to relieve it.
You can prevent most tooth decay with these tips:
If you have children, get them regular dental checkups, and take steps early to prevent tooth decay.
Current as of:
June 30, 2021
Author: Healthwise StaffMedical Review: Adam Husney MD - Family MedicineJohn Pope MD - PediatricsMartin J. Gabica MD - Family MedicineArden Christen DDS, MSD, MA, FACD - Dentistry
Current as of: June 30, 2021
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & John Pope MD - Pediatrics & Martin J. Gabica MD - Family Medicine & Arden Christen DDS, MSD, MA, FACD - Dentistry
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