How Do Cavities Form? Part I: Sugar

January 18, 2017
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Posted By: Dr. Richard Facko
smiling girl in dental chair | kids' dentist in Palos Heights IL

There are many myths and plenty of misinformation out there regarding cavity formation.  In this three-part series, I hope to dispel some of those myths and give you information that will help keep your child’s teeth healthy.

How do cavities form?

Cavity formation requires three things – sugar, bacteria, and time.  If any one of these three factors is missing, a cavity will not form.  While cavities form from the same factors, some individuals are certainly more prone to cavities than others.  For cavity-prone people, these ideas are even more important, as they will have to work harder to keep their teeth healthy than their peers.

What types of sugar cause cavities?

Fermentable carbohydrates, particularly sugar, are one of the three factors in cavity formation.  Almost all sugars can cause cavities, but some are more potent than others.

Lactose, the sugar found in cow’s milk, is not typically harmful to teeth.  Very long exposure times, such as taking a bottle or sippy cup to bed with cow’s milk, can be harmful.  But under normal conditions, we don’t find that white milk is harmful to teeth.

The sugar found in whole fruits, mostly fructose, is not harmful to teeth in its original form.  However, processed fruits, such as applesauce, fruit juice, fruit snacks, etc, are known to cause tooth decay.  Encourage your child to eat plenty of whole fruits for a healthy mouth and body.

Candy and sweet treats obviously have high levels of sugar.  However, I think it’s rare for any child to be consuming so many sweets that this is the main cause of their tooth decay.  Most people are aware of the harmful effects of candy, and limit their children’s exposure.  I often find that it’s the hidden sugar, such as that found in fruit juice, which causes the most problems.  But if your child is really consuming high levels of candy and sweets it would be good for dental health and overall health to cut back.

Finally, many children consume high levels of carbohydrates.  This can come in the form of noodles, crackers, goldfish, and many others.  While many of the labels on these food items don’t show high levels of sugar, we actually have enzymes in our saliva that begin breaking down carbohydrates into simple sugars before we even swallow!  Again, reducing exposure, rather than eliminating altogether, is a good way to minimize the risk for tooth decay.

Sugar is only one of the factors that contributes to tooth decay.  I hope that by identifying sources of sugar in your child’s diet you are better able to assess changes that might be helpful to maintain oral health.

Contact Our Palos Heights Pediatric Dental Office

If you have questions about how to help your child prevent cavities or want to schedule an appointment for your child, please contact our dental office today!

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