WebMD Medical Reference in collaboration with
Dental Health: Cavities
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.
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 only affect children, 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
gingivitis (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 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 filling made of silver alloy, gold, porcelain, or a composite resin.
Restorative materials used in fillings are considered safe. Concerns have been
raised over the safety of mercury-based, silver amalgams in particular, but 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.
Reviewed by the doctors at The Cleveland Clinic Department of Dentistry.
Edited by
Charlotte E. Grayson, MD, February 2003, WebMD.
Portions of this page © The Cleveland Clinic 2000-2003
Last Editorial Review: 5/1/2007
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