What Causes Cavities — and How to Prevent Them
Cavities are one of the most common dental issues, and they can happen at any age. A cavity forms when the hard outer layer of your tooth (the enamel) becomes weakened and allows bacteria to create a small opening. If it’s not treated, that opening can grow and eventually cause pain, sensitivity, or even infection.
The good news is that cavities are highly preventable once you understand what causes them.
What Actually Causes Cavities
Plaque buildup
Plaque is a thin, sticky film that naturally forms on your teeth. When you eat sugary or starchy foods, the bacteria in plaque create acids that slowly wear down your enamel. Over time, this can lead to small holes — cavities.
Not brushing and flossing consistently
If plaque isn’t removed regularly, it hardens and becomes much harder to clean off. Brushing twice a day with fluoride toothpaste and flossing daily are the simplest ways to keep plaque under control.
Sugary and acidic foods and drinks
Candy, soda, sports drinks, fruit juices, and even frequent snacking can increase the amount of acid in your mouth. More acid means more enamel erosion. Limiting these foods — or rinsing with water afterward — helps protect your teeth.
Dry mouth
Saliva is one of your body’s best defenses against cavities. It washes away food particles and helps neutralize acids. Certain medications, medical conditions, or simply not drinking enough water can reduce saliva and increase your risk.
Genetics
Some people naturally have deeper grooves in their teeth, softer enamel, or different saliva chemistry. If cavities run in your family, you may need to be a little more proactive with prevention.
Nutrition and overall health
A diet low in essential vitamins and minerals can weaken teeth. Conditions like diabetes can also increase cavity risk. A balanced diet supports stronger enamel and better oral health.
How to Prevent Cavities
Professional care and good daily habits work together to keep your teeth strong. Here are simple, effective ways to lower your risk:
- Brush twice a day with fluoride toothpaste
- Floss daily
- Limit sugary and acidic foods and drinks
- Rinse with water after sweets or acidic beverages
- Chew sugar‑free gum to boost saliva
- Use saliva substitutes if you struggle with dry mouth
- Keep up with regular dental checkups and cleanings
- Eat a balanced diet rich in vitamins and minerals
Your dentist may also recommend preventive treatments such as:
- Dental sealants (especially for children or adults with deep grooves)
- In‑office fluoride varnish
- Prescription-strength fluoride toothpaste
- Silver diamine fluoride in certain cases to stop early cavities without drilling
If You Do Get a Cavity
Cavities are very treatable when caught early. Most are repaired with a tooth‑colored filling. Larger areas of damage may need a porcelain inlay or onlay, and more advanced decay may require a root canal or, in severe cases, an extraction.
The sooner a cavity is treated, the simpler and more comfortable the repair will be.