Did you know over 80% of Americans1 have at least one cavity by the time they turn 34 years old. If that statistic sounds alarming, you can take some solace in knowing that tooth decay is avoidable with preventative dental care. A cavity is also very treatable with early identification and treatment. However, many people have cavities and don’t know it or don’t get treatment; the CDC estimates one in four adults in the U.S. have untreated cavities2. These statistics demonstrate why it's important to know the signs of a cavity — and we’re here to help you out!
This guide will help you learn the signs of a cavity to look so you can avoid more serious problems, such as an abscess or tooth loss.
Why cavities develop
Plaque is a sticky film of bacteria on your teeth caused by food, drinks, and saliva. If it isn’t removed via brushing, flossing, and regular dental checkups, it can wear down the hard layer of enamel that protects your teeth. Bacteria and acids can then form small holes, or cavities, in the tooth3. If it isn't addressed, this deterioration can continue down to the tooth pulp and ultimately result in tooth loss4.
Potential signs of a cavity
Small cavities may not have any symptoms at all4, which is why biannual dental exams are so crucial. The early stages of tooth decay may cause nothing more than white spots due to mineral loss5; however, they’re tough to spot without a trained eye.
As a cavity progresses, you may experience some of the following noticeable symptoms. Note that these are not definitive signs of a cavity — always consult with your dentist!
Toothache or sensitivity
This is usually the most obvious sign of a cavity. When holes form in enamel, they expose the underlying dentin. Dentin contains tissues that connect to the tooth’s nerves. When the dentin is exposed, it gets irritated by bacteria in your mouth and can potentially cause sensitivity or sharp, shooting pain. A variety of factors can exacerbate the discomfort, including cold air, chewing, brushing your teeth, and hot, cold, or sweet foods and drinks6. As a cavity worsens, mouth bacteria wears out the dentin and makes its way to the pulp, which often results in severe pain and can develop into an abscess if it isn’t treated quickly7.
Sensitivity and pain don’t necessarily mean you have a cavity. Some people have naturally thin enamel, and others can wear theirs down if they grind their teeth or brush too hard6. Cold and sweet foods can cause sensitivity if you have receding gums, which may expose the tooth root8. You can also experience sharp pain when a tooth is cracked or chipped. But when the sensitivity or pain is isolated to one tooth and you haven’t experienced a dental injury, it’s more likely to be caused by tooth decay6.
Visible holes in teeth
In some cases, the holes formed in your teeth by bacteria are difficult to see, whether it be due to their location (e.g., between the teeth) or size. But as more of the enamel deteriorates, it may form a hole large enough to see with the naked eye9.
Certain foods, beverages, tobacco, and aging can all stain your teeth. However, tooth decay is another potential cause. This isn’t the cavity itself — it’s the dentin, which is usually yellow, gray, or brown11. Dentin may become visible when enough enamel wears away due to decay10.
Bacteria, not cavities themselves, are the primary cause of bad breath. But since cavities form holes in your teeth that your toothbrush can’t reach, they provide a place for bacteria to build up. The result can be halitosis, or chronic bad breath11. In severe cases, bacteria can rot the pulp underneath the dentin, which can also cause bad breath12.
Swelling or bleeding gums
Plaque buildup can cause inflammation along the gumline, leading to swelling and bleeding. While these issues are often signs of gum disease, they can also signal a potential cavity — especially if the symptoms are localized around one tooth13.
How dentists treat tooth decay
For minor tooth decay, your dentist will recommend a filling to seal off the cavity and prevent it from spreading to other teeth. You may need a root canal for a more serious cavity.
Check out these other blog posts to learn more!
- What are your tooth filling options?
- What can you expect during a tooth filling?
- What is a root canal?