(Cavities; Dental Caries; Dental Decay)
Tooth decay is the destruction of tooth material, which includes:
Enamel—the hard outer surface of the tooth
Dentin—the second softer layer beneath the enamel
Pulp—the inside of the tooth containing the nerve and blood supply
Root—the area of the tooth anchoring it in the bone
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Everyone has bacteria in their mouths. The bacteria eat sugars that are left on the tooth, which then creates acid. The acid and the bacteria form plaque on the teeth. This plaque clings to the teeth. It holds the acid to the tooth. The acid wears away the tooth. Over time, the acid can lead to tooth decay.
Everyone is at risk for tooth decay. Factors that may increase your chance of tooth decay include:
Having poor dental hygiene
Having high numbers of bacteria in the mouth
Having an insufficient amount of fluoride (some communities in the United States add fluoride to the drinking water)
Taking medications that contain sugar or cause dry mouth
Eating a diet high in sugar
Enamel erosion from
gastroesophageal reflux disease
bulimia nervosa Malnourishment (such as vitamin and mineral deficiencies)
Having certain conditions that decrease the flow of saliva in the mouth, such as
Sjogren syndrome For children: having parents or siblings with severe tooth decay
Babies are also at risk for developing cavities. Habits that can increase the risk include giving a bottle between regular feedings or while in bed at night.
Tooth decay may cause:
Tooth sensitivity to hot or cold
Tooth discomfort after eating
Darkening of the tooth surface
Bad breath or a foul taste in the mouth
Throbbing, lingering pain in tooth
Tooth decay may be diagnosed over a period of time or at a single dental visit. This involves clinical examination as well as x-rays.
A dentist checks for tooth decay by:
Asking about pain in the teeth
Visually inspecting the surface of the teeth
Probing teeth with dental instruments to check for:
Sensitivity Pain Softness Surface defects Taking x-rays of teeth
Sometimes tooth decay will repair itself. This is most likely if it is caught early.
Treatment for more severe decay includes:
When decay reaches the dentin, the dentist will treat it by:
Numbing the tooth and surrounding tissue area
Removing the decay with instruments
Filling the hole with a dental filling; the filling can be silver or tooth colored
Tooth decay that reaches the pulp and/or root of the tooth is treated with a
The tooth is numbed and a hole is drilled through the top of the tooth.
Pus and dead tissue are removed from the tooth.
The inside of the tooth and the root (nerve) canals are cleaned and filled with a permanent filling.
The root (nerve) canal is sealed.
A crown is placed on the tooth to protect it.
Tooth Extraction (Removal)
may be necessary if:
Tooth decay and/or tooth infection is too extensive for filling or root canal.
A break or crack in the tooth that has allowed for decay is too severe to be repaired.
An extensive infection exists between the tooth and gum.
If the tooth is removed, it will be replaced with a:
To help reduce your chance of tooth decay:
Practice proper dental hygiene, including:
with fluoride toothpaste after meals or at least twice per day. Using a soft-bristled toothbrush or a powered toothbrush. Daily flossing
between teeth and gums—Bacteria living between the teeth can only be removed with floss or interdental cleaners. Getting regular dental check-ups and teeth cleaning (usually every 6 months).
Limit the amount of sugar and carbohydrates you eat and drink, including:
Honey Sodas and other sweetened drinks Candy Cakes Cookies Other sweets Rinse your mouth with water after eating sugars
Replace your toothbrush every 3 to 4 months
Avoid sugar-containing drinks (including fruit juices), especially in baby bottles
Chew gum with xylitol or sorbitol (may reduce your risk of developing cavities)
Talk to your dentist about the use of a
sealant. This is a protective plastic covering. It is applied to the chewing surfaces of teeth. Sealants usually last anywhere from 5-15 years.
Prevention is particularly important for children. Supplemental fluoride in early childhood can prevent early decay. The dose can be adjusted for the amount of natural or added fluoride in local water supplies. Fluoride can also be applied to permanent teeth as a long acting varnish. Re-varnishing is usually necessary at least twice yearly.
Academy of General Dentistry
Mouth Healthy—American Dental Association
http://www.mouthhealthy.org CANADIAN RESOURCES:
Canadian Dental Association
The Canadian Dental Hygienists Association
Fluoride for prevention of dental caries. EBSCO DynaMed Plus website. Available at:
. Updated November 21, 2016. Accessed August 22, 2017.
Murdoch-Kinch CA, Mclean ME. Minimally invasive dentistry.
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Seal out tooth decay. National Institute of Dental and Craniofacial Research website. Available at
...(Click grey area to select URL) Updated September 2016. Accessed August 22, 2017.
Selwitz RH, Ismail AL, Pitts NB. Dental caries.
Statement on early childhood caries. American Dental Association website. Available at:
...(Click grey area to select URL) Accessed August 22, 2017.
Tooth decay. National Institutes of Health website. Available at:
...(Click grey area to select URL) Accessed August 22, 2017.
Twetman S. Consistent evidence to support the use of xylitol- and sorbitol-containing chewing gum to prevent dental caries.
Evid Based Dent.
8/2/2012 DynaMed Plus Systematic Literature Surveillance
: Khadra-Eid J, Baudet D, Fourny M, Sellier E, Brun C, François P. Development of a screening scale for children at risk of baby bottle tooth decay.
5/17/2014 DynaMed Plus Systematic Literature Surveillance
Moyer VA, US Preventive Services Task Force. Prevention of dental caries in children from birth through age 5 years: US Preventive Services Task Force Recommendation Statement. Pediatrics. 2014;133(6):1102-1111.
7/15/2014 DynaMed Plus Systematic Literature Surveillance
: Yaacob M, Worthington HV, et al. Powered versus manual toothbrushing for oral health. Cochrane Database Syst Rev. 2014;6:CD002281.
Last reviewed September 2018 by
EBSCO Medical Review Board
Michael Woods, MD, FAAP Last Updated: 7/15/2014