Cavities occur as a result of tooth decay. Tooth decay is the destruction of tooth structure. Tooth decay can affect both the enamel (the outer coating of the tooth) and the dentin layer of the tooth (see diagram).
Tooth decay occurs when foods containing carbohydrates (sugars and starches) such as breads, cereals, milk, soda, fruits, cakes, or candy are left on the teeth. Bacteria that live in the mouth digest these foods, turning them into acids. The bacteria, acid, food debris, and saliva combine to form plaque, which clings to the teeth. The acids in plaque dissolve the enamel surface of the teeth, creating holes in the teeth called cavities, or caries.
Who gets cavities?
Many people think cavities affect children only, but changes that occur with aging make cavities an adult problem, too. Recession of the gums (a pulling away of gum tissue from the teeth), often associated with an increased incidence of gum disease, can expose tooth roots to plaque. Also, sugary food cravings in pregnant women can make them more vulnerable to developing cavities.
Decay around the edges of fillings is also common in older adults. Because many older adults lacked the benefits of fluoride and modern preventive dental care when they were growing up, they often have a number of dental fillings. Over the years, these fillings may weaken and can fracture, allowing bacteria to accumulate in the tiny crevices and causing tooth decay.
How do I know if I have a cavity?
Your dentist can discover cavities during your regular dental check-up. The tooth surface feels soft when probed by your dentist with a dental instrument. X-rays can also show cavities before they become visible to the eye.
In advanced stages of tooth decay, you might experience a toothache, especially after consuming sweet, hot, or cold foods or drinks. Other signs of tooth decay are visible pits or holes in the teeth.
How are cavities treated?
Cavities are treated in a number of different ways, depending on the extent of tooth decay. If decay is not extensive, the decayed portion of the tooth is removed by drilling and replaced with a restorative material such as silver alloy, gold, porcelain, or a composite resin filling. Restorative materials are considered safe. Concerns have been raised over the safety of mercury-based silver amalgams in particular, but these concerns are not supported by any credible evidence, and the ADA, FDA, and other public health agencies continue to support the safety of this restorative material. Allergies to silver amalgam are rare, as are allergies to other restorative materials.
If the decay is extensive and there is limited tooth structure remaining, crowns will be used. If a crown is needed, the decayed or weakened area of the tooth is removed and repaired and a crown is fitted over the remainder of the tooth. Crowns are made from gold, porcelain, or porcelain fused to metal.
If the decay causes the nerve or pulp of the tooth to die, a root canal will be performed. During this procedure, the center of the tooth (including the nerve, blood vessel, and tissue) is removed along with the decayed portions of the tooth. The roots are then filled with a sealing material. If necessary, a crown can be placed over the filled tooth.
Several new treatments are under development. One experimental technique uses fluorescent light to detect the development of cavities long before they can be detected by traditional means, such as x-rays or dental examination. In many cases, if cavities can be detected early, the decay process can be stopped or reversed.
Researchers are also working on a "smart filling" to prevent further tooth decay by slowly releasing fluoride over time around fillings and in adjacent teeth.
How can I prevent tooth decay?
To prevent tooth decay:
- Brush your teeth at least twice a day with a fluoride-containing toothpaste, preferably after each meal and especially before going to bed.
- Clean between your teeth daily with floss or interdental cleaners, such as the Oral-B Interdental Brush, Reach Stim-U-Dent, or Sulcabrush.
- Eat nutritious and balanced meals and limit snacks. Avoid carbohydrates, such as candy, pretzels, and chips, which can remain on the tooth surface especially between meals.. If you eat sticky foods, brush your teeth afterwards.
- Check with your dentist about use of supplemental fluoride, which strengthens your teeth.
- Ask your dentist about dental sealants (a plastic protective coating) applied to the chewing surfaces of your back teeth (molars) to protect them from decay.
- Drink fluoridated water. At least a pint of fluoridated water each day is needed to protect children from tooth decay.
- Visit your dentist regularly for professional cleanings and oral examination.
Researchers are developing new means to prevent tooth decay. A study has shown that a chewing gum that contains the sweetener xylitol temporarily retarded the growth of bacteria that cause tooth decay. In addition, several materials that slowly release fluoride over time, which will help prevent further decay, are being explored. These materials would be placed between teeth or in pits and fissures of teeth. Toothpastes and mouth rinses that can reverse and "heal" early cavities are also being studied.
- Caries (tooth decay) Mouth Healthy. American Dental Association www.ada.org Accessed 11/2012
- Klein U. Chapter 16. Oral Medicine & Dentistry. In: Way WW, Hay WW, Levin MJ, Sondheimer JM, Deterding RR, eds. CURRENT Diagnosis & Treatment: Pediatrics. 20th ed. New York: McGraw-Hill; 2011.
- Take Care of Your Child’s Teeth. US Department of Health and Human Services. www.healthfinder.gov Accessed 11/2012
- Dental Hygiene: How to Care for Your Child’s Teeth. American Academy of Family Physicians. familydoctor.org Accessed 11/2012
- Cavity. KidsHealth. Nemours. kidshealth.org Accessed 11/2012
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 11/23/2012...#10946