Readers ask, we answer: How can I tell if I have a cavity?

Sabrina asks:

“Is there an easy way to tell if I have a cavity?"

Did you know...?

92% of adults 20 to 64 have had cavities in their permanent teeth, according to the National Institute of Dental and Craniofacial Research.

Hi, Sabrina. Not really. There’s no surefire way to identify decay without a professional evaluation, so it’s best to ask your dentist if you think you might have a cavity.

Cavities form as acid and bacteria in the mouth wear down the surface of your tooth, called the enamel. A cavity is the hole that develops as this protective layer of your tooth breaks down. You might notice it as a dark spot on the tooth. But your dentist can take a closer look to see if the spot is actually a cavity.

Tooth decay is one of the most common causes of dark spots on teeth. But sometimes spots are just surface stains caused by foods or drinks. Staining can be easily removed during a dental cleaning or teeth whitening. Certain medications can also cause stains on the teeth. A spot can also be a sign that the tooth has been injured.

During a dental exam, your dentist will use a pointy tool called a dental explorer to check any suspicious spots on your teeth. If the spot feels hard, it’s generally not a cavity. Healthy enamel is the hardest substance in the human body. If the spot feels “sticky,” though, it’s a good sign you have a cavity. The stickiness is the softening of your enamel by bacteria.

When cavities begin, they only affect the enamel. This layer of the tooth doesn’t contain nerve endings, so you won’t feel any pain. If a cavity grows large enough, it can reveal the next layer of the tooth, called the dentin. This can cause sensitivity to hot, cold and pressure. An untreated cavity can eventually spread infection to the root of the tooth, causing intense pain.

The best way to keep an eye on cavities is to visit your dentist regularly for cleanings and exams. And if you’ve noticed any sensitivity, pain or lasting dark spots on your teeth, don’t hesitate to schedule an appointment with your dentist.

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