What Really Causes Cavities

From a young age we are taught that brushing and flossing daily can help to prevent cavities. While practicing quality oral hygiene can greatly improve your oral health, a number of other factors can determine whether your teeth stay healthy and strong. However, since most people believe that brushing and flossing will take care of all of their oral care needs, a lot of misinformation gets spread about the causes of cavities. To help you separate fact from fiction, here are some common cavity myths along with a few facts.

Myth: The Primary Cause of Cavities is Sugar
As kids we often hear that eating sugar will rot our teeth. While this is a convenient statement to tell children in order to get them to eat less candy, it isn’t entirely true. Plaque, a sticky bacteria biofilm that grows in the mouth, thrives off of the sugars we consume to produce acids that slowly eat away at tooth enamel. Over the following months and years, these acids can wear small holes in tooth enamel where bacteria can begin to accumulate, which cause tooth decay and cavities. The more sugar a person eats, the more fuel they provide plaque with to produce acids. So while sugar itself doesn’t exactly cause cavities, it can contribute to them.

Fact: Eating Foods High in Acid Causes Tooth Decay
Diets high in acidic fruits like lemons, pineapples, or tomatoes can lead to enamel erosion. When you consume these types of foods, you raise the acidity levels in your mouth, which causes your enamel to become weakened. When enamel becomes weakened, it is more susceptible to plaque acids and other forms of trauma.

Myth: Kids Get More Cavities than Adults
Over the last 20 years, the development of new sealants, use of fluoridated water, and advances in preventative care has cut the number of cavities found in children in half. While children have been getting fewer cavities, seniors have actually seen a dramatic increase in cavities in recent years. Even though researchers don’t know the exact cause, they suspect that more seniors are taking medications that cause dry mouth as a symptom. Dry mouth causes the body to produce less saliva, which normally acts as a natural neutralizing agent against plaque acids.

Fact: Cavities Occur More Frequently Between Gaps in Teeth
Individuals with small gaps between their teeth that make flossing or brushing difficult have a higher risk of developing cavities in these areas. Big gaps between teeth make brushing and flossing easier and therefore make cavities less likely to occur.

Myth: All Fillings Need Replacing
Whether you need to have a filling replaced at some point depends more on the tooth than the type of you filling. If the structure of the tooth remains strong, and no new cavities develop, than amalgam and composite fillings never need replacing. However, new porcelain fillings may need to be replaced once every 10 years or so.

Fact: Cracked Teeth Causes Decay
When cracks begin to form in tooth enamel, they expose the delicate layer beneath, called the dentin, to bacteria. Over time, this bacteria begins to pool and can cause inflammation, which leads to decay and cavities.

Timothy Lemke is a freelance writer whose oral health knowledge came from working with Dr. Lance Baily, a Portland dentist.