Updated on March 12, 2024
2 min read

Cavity vs. Stain: How to Tell the Difference

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Cavity vs. Stain: How to Tell the Difference

If you’ve recently noticed discoloration on one or more of your teeth, you might have trouble figuring out whether it’s a cavity or a stain.

Cavities and stains can make parts of your teeth appear darker. Many things that cause staining can also contribute to cavities. But a few key details can help you tell the difference between the two.

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What Does a Cavity Look Like?

A cavity may appear as a brown, black, or gray spot on a tooth. It may also be sticky. The size of the discolored area will likely stay the same over time.

Close up shot of 3d render human teeth with focused hole on tooth due to cavities

Cavities result from bacteria feeding on sugars that enter your mouth. These bacteria create acids that dissolve the mineral content of your teeth over time. This process is known as tooth decay.

Other Cavity Symptoms

Tooth decay is likely to have other symptoms besides discoloration, especially as it progresses. Be on the lookout for issues like:

  • Visible holes in teeth
  • Tooth sensitivity, especially in the discolored area
  • Toothache, which may remain constant or radiate to the ear or jaw area
  • Bad breath or foul taste that doesn’t go away

If you leave a cavity unchecked, it won’t go away. In most cases, it will slowly expand over time.

What Does a Stain Look Like?

While a cavity usually appears as a discolored area or hole on the surface of a tooth, stains tend to be more evenly spread. If you notice that an entire tooth or group of teeth is a different color, you’re probably looking at a stain rather than tooth decay.

Brown Stain on the lower part of teeth and borderline of the gums due to dental problems

Stained teeth generally have what’s known as extrinsic discoloration. This means the stain isn’t part of the tooth and can probably be removed.

In some cases, teeth show intrinsic discoloration, which may reflect a condition you were born with, certain medications, or an injury. This type of discoloration isn’t as easy to remedy.

While stained teeth are unpleasant, they’re generally not accompanied by cavity-related pain or discomfort. Most of these causes of tooth staining are avoidable. However, prolonged poor oral hygiene can make them harder to remove.

More Reading


A cavity (or tooth decay) can sometimes look similar to a tooth stain and vice versa. Usually, you can tell the difference with a closer look.

Generally, a cavity affects a defined area of a tooth, whereas stained teeth tend to affect more than one tooth. Various foods, drinks, and habits can stain your teeth. Drinks like coffee, tea, and wine are major culprits, as is tobacco use.

Oral bacteria causes tooth decay. Cavities are damaged parts of teeth that have begun to decay.

Both tooth stains and cavities can be treated professionally. They can also both be prevented with regular oral hygiene and careful attention to diet and other oral habits.

Last updated on March 12, 2024
6 Sources Cited
Last updated on March 12, 2024
All NewMouth content is medically reviewed and fact-checked by a licensed dentist or orthodontist to ensure the information is factual, current, and relevant.

We have strict sourcing guidelines and only cite from current scientific research, such as scholarly articles, dentistry textbooks, government agencies, and medical journals. This also includes information provided by the American Dental Association (ADA), the American Association of Orthodontics (AAO), and the American Academy of Pediatrics (AAP).
  1. Featherstone, J. “Dental caries: a dynamic disease process.Australian Dental Journal, 2008.
  2. Rajendran A and Sivapathasundharam B. Shafer’s Textbook of Oral Pathology (7th ed.) Elsevier Health Sciences APAC, 2014.
  3. Masterson, et al. “Shades of Decay: The Meanings of Tooth Discoloration and Deterioration to Mexican Immigrant Caregivers of Young Children.Human organization, 2014.
  4. Prathap, et. al. “Extrinsic stains and management: A new insight.J. Acad. Indus. Res., 2013.
  5. G., Shobana, et al. “Effect of Whitening Toothpastes on Extrinsic Dental Stains.Journal of Advanced Oral Research, 2019.
  6. Middleton A. “Tooth whitening versus stain removal.BDJ Team, 2017.
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