Cavity Signs and Symptoms - What to Look For

Cavity Signs and Symptoms - What to Look For
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Cavity Signs and Symptoms - What to Look ForClinical Content Reviewed by Dr. Jay Khorsandi, DDS
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Table of Contents

  1. What Is a Cavity?
  2. How Does a Cavity Develop?
  3. Symptoms of a Cavity
  4. What Does a Cavity Look Like?
  5. When Should You See a Dentist?
  6. References

The average adult, and most teenagers and children for that matter, have had a cavity. If you’re reading this, you’ve almost certainly had a filling after visiting the dentist for a routine checkup and cleaning. About 80% of adults have a cavity by the time they reach their mid-30s, according to The Cleveland Clinic.

While small cavities are pretty much just part of life for most people, few people really understand what they are. Recognizing the signs and symptoms of a developing cavity can be useful for patients though. After all, a cavity that’s treated early is simple – decay that’s left unchecked can lead to serious complications.

What Is a Cavity?

Cavities, also referred to as dental caries, are damaged areas of any tooth that develop over time. This damage is permanent, often developing into tiny holes that are hard to see or feel on your own. Large cavities may be visible to the naked eye.

Extremely common, cavities are a routine sight during checkups and cleanings for your dentist. While children, teenagers and older adults are more likely to get them, it’s not all uncommon for adults in their 30s, 40s and 50s to develop a cavity that needs professional treatment from a dentist.

How Does a Cavity Develop?

Cavities form when acid in your mouth erodes your dental enamel. While there are a variety of reasons this can happen. For instance, consuming too many sugar-rich foods and drinks is one reason children and teenagers develop cavities at a higher rate than adults.

The process starts with plaque formation, which stems from eating foods high in sugar and starch without following up with a proper dental cleaning routine. Plaque that remains on the teeth can turn into tartar under the gumline, making it a lot more difficult to remove.

Once plaque and potentially tartar take root, the unique acids in dental plaque begin to remove vital minerals from your enamel. This is how small cavities start.

Without treatment, tooth decay will continue to develop past your enamel and impact the inner structure of your teeth, referred to as the pulp. This area contains a variety of nerves and blood vessels.

Once this happens, patients often begin to feel some sort of pain or pressure as the pulp structure swells inside the tooth. Unfortunately, there’s no room for expansion within a tooth and this often leads to more severe pain over time.

Symptoms of a Cavity

When cavities first form, there’s a good chance you won’t notice them. Tiny, microscopic holes that only your dentist can see with special magnifying tools are, technically, cavities.

Over time, you may notice symptoms of cavities. Among the most prevalent:

  • Tooth sensitivity. Most people associate cavities with pain, but sensitivity is an early warning sign that you have decay. You may notice that your teeth are especially sensitive to hot and cold food and drinks and hard food items like nuts. Sweet foods may also cause twinges of discomfort.
  • Bad breath. Bad breath can be a sign that you’ve got decay in your mouth. Bad breath that won’t go away can also be a sign of more serious gingivitis or periodontitis.
  • Pain when you chew or bite down. Pain can range from minor discomfort to more serious pain that’s strong and sharp. Once you’ve reached this stage you generally have an advanced cavity that requires dental intervention as soon as possible.
  • Spontaneous dental pain. If you have a cavity, you may notice that a certain tooth or part of your mouth hurts even when you’re not eating or drinking. With cavities, pain can come and go, and it doesn’t always need to be triggered by eating or drinking.
  • Clearly visible holes or small pits on your teeth. You may see these holes or you may feel them ever so slightly with your tongue, particularly with back molars. For this reason, it’s a good idea to visually inspect your teeth in the mirror on a regular basis.
  • Brown or black stains on your teeth. As cavities progress, signs of decay may be visible to the naked eye. Even small brown or black spots require treatment to keep decay from spreading to other parts of your tooth structure.
  • Your gums feel tender, look swollen or bleed when you brush or floss. Though this can be a sign of other factors like gum diseases, swollen or bloody gums can accompany a cavity, particularly if that cavity is located toward the gumline or root of the tooth.

What Does a Cavity Look Like?

In many cases, you won’t be able to see a cavity that’s just starting to form within your mouth. That’s the ideal time to have it treated, or at the very least, put on a watch list by your dentist.

At this stage, your dentist may only be able to see your cavity with special magnification tools or as a dark shadow on an X-ray. This is one main reason your dentist typically performs those X-rays every few cleanings.

As cavities progress, you may see small holes or pits on the surface of your teeth. Small black or brown spots are also a common sign that you’re dealing with tooth decay.

Over time, these holes, pits and spots are likely to get bigger. Once this happens, spotting them in the mirror will be easy.

When Should You See a Dentist?

Most people don’t realize that they have a cavity forming for some time after the process begins. That’s why regular dental checkups and cleanings are a vital part of your oral health routine. With regular checkups and cleanings, your dentist will be able to spot cavities before they become painful or problematic.

If you feel you may have a cavity or tooth decay is causing you discomfort, calling your dentist right away is a must. Minor cavities may be able to wait until your next cleaning for repair, but painful cavities, large holes and oversized black or brown spots may need treatment before that.


Cavities/Tooth Decay. (July 2017). Mayo Clinic. Date fetched: July 27, 2021.

Cavities. (September 2020). Cleveland Clinic. Date fetched: July 27, 2021.

Cavities: What Are They and How Do We Prevent Them. Mouth Healthy. Date fetched: July 27, 2021.

Disclaimer: This article is intended to promote understanding of and knowledge about general oral health topics. It is not intended to serve as dental or other professional health advice and is not intended to be used for diagnosis or treatment of any condition or symptom. You should consult a dentist or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment.