How Do You Know If You Have a Cavity? 8 Signs to Watch For

Cavities are the second most common health issue in the United States, with over 3 million new cases reported each year.  But how can you tell if you have a cavity—or if one is quietly developing?  In this article, I have compiled a detailed guide highlighting eight of the most common signs of a cavity forming.

1. Persistent Toothache or Pain: A toothache is one of the most classic signs of a developing cavity—especially when pain occurs upon contact with something hot, cold, sweet, or when pressure is applied. This pain may be sharp and sudden, or dull and throbbing. You might feel it in the gums below the tooth or within the tooth itself. If you're experiencing this kind of discomfort, come see me!

2. Pain When Chewing: If chewing food triggers pain, it might be due to a crack or a cavity in the tooth. Sharp, sudden pain when biting down could indicate nerve exposure or infection. A helpful test is to gently tap the tooth with a spoon or try drinking something hot or cold to check for sensitivity. If the pain is severe, book an appointment right away.

3. Bad Breath or Bad Taste in the Mouth: Cavities create small, infected holes in teeth that trap food and bacteria, leading to foul odors. Bacteria buildup from untreated cavities can leave a persistent sour taste. Chronic bad breath could also be a sign of gum disease. Either way, a dental visit is recommended.

4. Sensitivity to Temperature: Roughly 80% of people over 17 have had at least one cavity.  A common symptom is sensitivity to hot or cold foods and drinks.  This happens when the cavity grows closer to the nerve inside your tooth.  If sipping a hot drink or enjoying ice cream causes pain, you might have a cavity forming.

5. Bleeding When Brushing: If you notice blood while brushing, it could be due to gum irritation caused by a deep cavity or a developing gum disorder. Food stuck near the gum line because of a cavity can aggravate the gums and lead to bleeding. Don’t ignore recurring bleeding—schedule an exam.

6. Dark Spots or Discoloration on Teeth: Not all cavities look like holes—some appear as brown, black, or even white spots. These can be signs of decay or stains, especially if the spot is soft or sticky to the touch. Sometimes, the whole tooth may darken or become prone to breaking. Discoloration is worth checking out.

7. Pain from Pressure Changes (Flying or Diving): Experiencing tooth pain when flying or diving can signal a cavity. Pressure changes may irritate nerves in decayed teeth, causing sudden discomfort. Catching these cavities early means simpler, less invasive treatment.

8. Swelling in the Gums: Swelling in a specific part of the gum line can indicate an infected nerve caused by a deep cavity. This may lead to abscesses or further infection. If you notice any localized swelling, contact me to investigate the source.

Cavities are easily treatable—but only if they’re caught in time. If you're experiencing any of these symptoms, I suggest you make an appointment as soon as possible.  Our gentle, comprehensive care can catch decay early and keep your smile healthy.