The two best defenses against tooth decay and gum disease are a healthy, well-balanced diet and good oral hygiene, including daily brushing with fluoride toothpaste, flossing and rinsing. Your body's own saliva is also an excellent cavity fighter, because it contains special chemicals that rinse away many harmful materials.
If you have any of the following symptoms, you may have a cavity:
• Unusual sensitivity to hot and cold water or foods.
• A localized pain in your tooth or near the gum line.
• Teeth that change color.