Definition

Tooth Decay (Caries or Cavities)

Choose a preferred language


What is tooth decay (caries or cavities)?

Tooth decay is the disease known as caries or cavities. It's caused by certain bacteria in the mouth that thrive on sugars and refined carbohydrates and make acids as a side effect. The acids attach to the hard outer layer of your tooth (enamel) first. The acids eventually penetrate into the tooth to the softer mineral inside the tooth (dentin). If not treated, the tooth decay can destroy large areas of the tooth and infect the nerve (pulp) and blood vessels at the center of the tooth. In older adults, exposed root surfaces are also at risk for decay. Tooth decay is a highly preventable disease with many contributing factors.


Who is at risk for tooth decay?

Everyone who has teeth is at risk for tooth decay. We all host bacteria in our mouths, which makes everyone a potential target for cavities. Risk factors that increase the risk for tooth decay include:

  • A diet high in sweets, refined carbohydrates, and sugars.

  • Living in communities with limited or no fluoridated water supplies.

  • Poor oral hygiene.

  • Reduced flow of saliva.

  • Being a child.

  • Being an older adult.


Preventing tooth decay

Preventing tooth decay and cavities involves 7 simple steps:

  • Brush your teeth and tongue twice a day, for at least 2 minutes at a time with a fluoridated toothpaste. Brushing with fluoride toothpaste should start when a child gets their first tooth. Use only a very small amount, about the size of a grain of rice.

  • Floss your teeth daily. Make sure to floss below the gums.

  • Eat a well-balanced diet and limit or eliminate sugary snacks and drinks.

  • Consult your health care provider or dentist about supplemental use of fluoride or dental sealants to protect family members' teeth.

  • Ask about fluoride varnish, which can be applied to teeth every 3 to 6 months.

  • Schedule routine dental cleanings and exams every 6 months for yourself and your family.

  • Stay well hydrated by drinking enough water.

Online Medical Reviewer: Jessica Gotwals RN BSN MPH

Online Medical Reviewer: Michael Kapner MD

Online Medical Reviewer: Rita Sather RN

Date Last Reviewed: 02/28/2025

© 2000-2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

Get Connected to a Care Manager

Get Connected
Related Articles
Read article
Flossing

Detailed information on the importance of correct flossing method.

Read article
Dental Care
Brushing and Toothpaste

Detailed information on brushing and toothpaste.

Read article
Wellness
How to Keep Your Gums and Teeth Healthy

Brushing and flossing your teeth are not hard to do. And doing both correctly can help prevent gum disease and tooth loss.

Read article
Dental Care
The Best and Worst Foods for Your Teeth

If you are what you eat, that's even more true for your teeth and gums. When you drink and eat starchy foods, you're not only feeding yourself--you're feeding the plaque that can cause havoc in your mouth.