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What Causes Cavities in a Child?

Team Pediatric Dentistry

Cavities are the most common chronic disease in children in the United States. Also known as tooth decay or dental caries, cavities are permanently damaged areas of tooth enamel, which is the outer layer of teeth. In other words, cavities are holes in the tooth enamel. Left untreated, cavities can cause toothaches, infection, and even the loss of teeth.

Cavities can develop for a wide variety of reasons.

Bacteria in the mouth

Billions of bacteria live in the mouth. These bacteria feed on the sugars and starches in food. As they eat, the bacteria create acids. These acids combine with the bacteria, food, and saliva to form plaque, which is a clear, sticky film that coats the teeth and gums. Left in place, the acids in plaque eat away at the child’s tooth enamel and creates cavities.

Many parents are surprised to learn that cavity-causing bacteria can be transmitted to children through saliva. Mothers and fathers can pass these bacteria to their children by kissing their kids on the mouth or by sharing food or beverages. The more frequently a child comes into contact with saliva containing these bacteria, the more likely the child will be to develop cavities.

Dietary habits

Bacteria love sugar, so frequent consumption of sugary foods and drinks can cause cavities in kids. Any type of carbohydrate, especially processed foods like potato chips, white crackers, and white bread, can cause cavities. This is because the body breaks down carbohydrates into simple sugars while the carbohydrate is still in the child’s mouth.

Surprisingly, the total amount of sugar and carbohydrates in a child’s mouth is not as important as the frequency at which a child eats such foods and the amount of time these foods stay in the child’s mouth. In other words, eating small amounts of sugar all day is worse than eating the treats all at once.

Defects in dental enamel

Certain types of defects may increase a child’s risk of developing tooth decay. Some defects are hereditary, passed from one generation to the next. Other enamel defects are the result of environmental factors, such as low birth weight, dental trauma, or viral or bacterial infections.

Poor oral hygiene

Poor oral hygiene in kids increases their risk of developing cavities. It is never too early to start good oral hygiene. A parent can reduce the risk of cavities in very young children by brushing their baby’s teeth twice a day as soon as the first tooth emerges; flossing should start as soon as the child has two teeth that touch.

Brushing twice a day and flossing once daily removes the plaque and bacteria that causes cavities. Using fluoride toothpaste helps strengthen a child’s dental enamel.

Mouth breathing

Saliva helps protect teeth by washing away food particles and repairing damage that bacteria inflict on enamel. A dry mouth can leave teeth unprotected by saliva and therefore more vulnerable to cavity-causing bacteria. Kids who breathe through their mouths instead of their noses may have an increased risk for dry mouth and for cavities. Pediatric dentists can recommend an orthodontic appliance to help correct mouth breathing.

A pediatric dentist can diagnose cavities in kids. These specially-trained dentists can also treat cavities and help children avoid cavities in the future. For more information on what causes cavities in kids, consult with your pediatric dentist.


Contact our office today if you would like to learn more. Call us at (516) 625-3806 or request an appointment online.