Tooth Decay

What is tooth decay?

Tooth decay is an area on a tooth that has been damaged. It’s also called a cavity. Cavities can be on the chewing surface of the tooth, around the base of the tooth, or near a previous filling.

What is the cause?

The main cause of tooth decay is plaque. Plaque is a sticky material made of mucus and saliva, food particles, and bacteria. Bacteria in the plaque lives off the simple sugars and starches in the foods you eat. The bacteria creates an acid that slowly destroys tooth enamel. Enamel is the outer, hard, glossy layer of a tooth.

After the enamel is destroyed, the acid attacks the soft inner layer of the tooth. This causes pain and the cavity gets bigger. If bacteria infect the inside of the tooth, they can damage the nerve.

What are the symptoms?

Early dental decay often causes no discomfort. After decay has destroyed much of the hard, outer portion of the tooth, you may get a toothache when you eat hot, cold, or sweet foods.

If the cavity is not treated, decay destroys more of the tooth. You may have pain, bad breath, a bad taste in your mouth, and possibly gum swelling and bleeding.

How is it diagnosed?

When checking for signs of decay, your dentist and dental hygienist look for:

  • Cracks or breaks in your teeth
  • Broken or leaking fillings or crowns
  • Soft areas on tooth enamel
  • Bleeding and swelling of the gums

You may also have X-rays to check for decay in the deeper parts of your teeth.

How is it treated?

To treat tooth decay, your dentist removes the decayed portion of the tooth and puts in a filling or crown. A crown is a tooth-shaped cover cemented on top of a tooth.

Fillings and crowns last 4 to 20 years, depending on the material used. As filling materials age and break down, they need to be replaced.

How can I take care of myself?

If you have tooth pain, see your dentist for treatment. Until you can see your dentist, take these steps to help relieve the pain:

  • Take nonprescription pain medicine, such as acetaminophen, ibuprofen, or naproxen. Read the label and take as directed. Unless recommended by your healthcare provider, you should not take these medicines for more than 10 days.
    • Nonsteroidal anti-inflammatory medicines (NSAIDs), such as ibuprofen, naproxen, and aspirin, may cause stomach bleeding and other problems. These risks increase with age.
    • Acetaminophen may cause liver damage or other problems. Unless recommended by your provider, don’t take more than 3000 milligrams (mg) in 24 hours. To make sure you don’t take too much, check other medicines you take to see if they also contain acetaminophen. Ask your provider if you need to avoid drinking alcohol while taking this medicine.
  • Stay away from hot, cold, or sweet foods or liquids that cause discomfort.
  • Chew on the side that doesn’t cause pain.

Ask your dentist what symptoms or problems you should watch for and what to do if you have them.

Make sure you know when you should come back for a checkup.

How can I help prevent tooth decay?

To help prevent tooth decay:

  • Brush your teeth correctly for at least 2 minutes twice a day. The most important time to brush is before you go to bed at night.
  • Floss correctly between your teeth once a day.
  • Gently massage your gums with a soft toothbrush.
  • Rinse daily with a fluoride or antibacterial, alcohol-free mouthwash.
  • Limit starchy or sugary foods that can lead to tooth decay or brush your teeth right after you eat these foods. Rinsing with water or chewing sugarless gum after you eat or drink foods that contain sugar can also help. Chewing gums sweetened with Xylitol can reduce and control bacteria in your mouth.
  • Limit acidic drinks, such as sports and energy drinks. They contain a high amount of acid that can break down the outside of your teeth. If you drink acidic drinks, rinse your mouth with water after.
  • Have regular dental checkups and cleaning, including X-rays. You may want to ask your dentist about a fluoride treatment and sealants for teeth.
Developed by RelayHealth.
Adult Advisor 2015.1 published by RelayHealth.
Last modified: 2015-02-03
Last reviewed: 2015-01-19
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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