MK Dental Care welcomes questions from our patients about what causes dental decay in youngsters, so feel free to speak to any of us at your next appointment. We have lots of information and leaflets about dental health education, and we have a computer program that patients can use which we have found exceptionally useful.

What causes a cavity?

By Kimberly A. Loos, D.D.S.

By understanding the cause of a cavity, patients might be better able to prevent them. Cavities are actually caused by a chain of events that start when food is allowed to remain on your teeth. The worst culprit is sugar because it is easily digested by the bacteria that naturally live in your mouth. However, any food left on the tooth surface long enough will eventually become sustenance for the bacteria. Once the bacteria, a component of plaque, digest the food, they produce an acid. It is this acid which eats away at the enamel (outer layer of tooth) eventually causing a "hole" in your tooth. The best way to prevent cavities is by practicing good oral hygiene. Plaque also causes gum disease, which is a major cause of tooth loss in people over the age of 35. So, there are now at least two good reasons to brush and floss your teeth regularly!

Tooth enamel consists of a substance called hydroxyapatite. Dissolving hydroxyapatite is called demineralization, and its formation is called remineralization. In the mouth there is an equilibrium between these two processes which is established even with healthy teeth.

Do you know any chemistry? When sugar ferments on teeth, hydrogen ions are produced that upset the equilibrium between demineralization and remineralization by combining with hydroxide ions to form water. Removal of hydroxide ions causes more of the hydroxyapatite to dissolve, resulting in tooth decay. Fluoride helps prevent tooth decay by replacing the hydroxide ions in hydroxyapatite. The resulting chemical compound is very resistant to acid attack!