6 common tooth infection symptoms you shouldn’t ignore

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There are some minor dental problems that may not need urgent attention, but a dental infection is not one of them.

If a dental infection or an abscess is left untreated you could end up losing teeth, risking some of the bone in your jaw, or end up with an infection in other areas of your body if the infection spreads. Dental infections are common and 90% of adults over 20 have some form of tooth decay, which can lead to a tooth infection.¹

In most cases, dental infections may be easy to treat, but it’s important to get treatment and eliminate the cause of the infection. If you start to have pain in a tooth or gums, or if you think that you might have a dental infection, you should get looked at by a dentist as soon as possible.

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What causes a tooth infection?

A dental infection is sometimes called an abscess. An abscess can develop when the bacteria that’s part of tooth decay gets inside a tooth or a part of the gums and becomes an infection. The infection will get worse as the bacteria feed on the sugars that are typically found in your mouth. When dental infections aren’t treated, they can likely eat away at your tooth until the nerve of the tooth is exposed, which is painful. If the infection goes deep into the tooth all the way down to the pulp and kills the pulp, which could lead to severe tooth decay. If there is a lot of damage to the pulp, your dentist may need to do a root canal in order to flush the infection and seal the tooth to help prevent it from getting infected again. The following are three typical  causes of dental infections²: 

Tooth decay

The bacteria that is always in your mouth can enter the tooth through cavities or small holes in the enamel of the tooth likely causing tooth decay. The bacteria will eat its way down through the tooth until it gets to the pulp of the tooth. There’s no way to rid your mouth of bacteria, although practicing good oral hygiene can help reduce the amount of bacteria that is in your mouth. So there’s no foolproof way to prevent dental infections. All you can do is help lower the risk of infection. 

Periodontal disease

Periodontal disease is likely the result of inflammation and infections in the gums and in the bone surrounding the teeth. According to the CDC³ approximately 47% of adults over 30 have some form of periodontal disease. The chances of developing periodontal disease increase as you age so as you get older it’s even more important to take care of your mouth and teeth. Brushing regularly is an easy way to help lower your risk of developing periodontal disease. When a dental infection is the result of periodontal disease the infection typically doesn’t settle in the tooth. Instead, the infection is typically present around the tooth in the gums. The bacteria causing the infection can eat away the gum tissue and bone⁴. 

Cracked tooth

If there is a crack in one of your teeth, tooth decay can likely get into the tooth through the crack and start burrowing down through the layers of the tooth to get to the pulp. If you have a significant crack in your tooth you’re likely to notice, but if the crack is very small you might not even realize it’s there. You may have cracked your tooth eating something tough like popcorn kernels or nuts, or you might have cracked a tooth accidentally and not know it is cracked. Cracks that might not be noticeable or cause you any obvious pain still are likely to allow for microscopic bacteria to get inside your tooth. 

Not all tooth infections are likely to cause severe symptoms, so you may not even realize that you have a tooth infection. Watch for these common signs of tooth infection if you start to feel like something is off in your mouth. 

Tooth infection symptoms

There are different symptoms that could indicate you have a tooth infection. Any one of these signs may not indicate an infection, but if you have several of these symptoms or if you have severe pain then you should see a dentist.⁵

1. Toothache

Toothache pain generally is from the nerve of the tooth being exposed. If you have a dental infection you may probably feel a throbbing pain that feels like it’s deep inside your tooth. You may have tooth pain for other reasons though, so be watching to see if you develop any other symptoms of an infection. 

2. Sensitivity

Tooth sensitivity, like toothache pain, doesn’t necessarily mean that you have a dental infection. Many people may experience a painful sensation when they bite something cold or drink something hot because of other reasons. If the sensitivity comes on fast, or if you experience intense sensations when you are eating some cold or drinking something warm then it could be an infection and you should see a dentist. 

3. Swelling

If you have a severe infection your cheek may swell as a result. The swelling might be slight if the infection is in a tooth but if the infection is in your gums you could find that the entire side of your face swells⁶. If you do have severe swelling that’s a sign of an infection and you should get to urgent care or to a dentist right away. If the bacteria gets deep into your gum or into the jawbone, it could spread from there throughout your body and cause other medical problems. 

4. Fever

It’s typically normal for your temperature to be a degree or two warmer than usual if you’re having some dental problems, but if your temperature is highly elevated or if your temperature doesn’t go back down to normal in a day or two then don’t wait to see a dentist or a doctor. Fever is your body’s way of attacking or fighting off an infection.

5. Swollen or tender lymph nodes 

The lymphatic system is like the drainage system of your body, and it’s usually effective at filtering waste and keeping all your cells cleaned out and healthy⁷. But when you have an infection or if your body is responding to some type of inflammation your lymph nodes can typically swell. Many lymph nodes are located in your head and neck. If the lymph nodes in your face and neck swell, or if they feel hard when you touch them then you may have an infection⁸. If you notice that your lymph nodes are swollen or tender that is likely a sign that you may have an infection and you should contact your dentist. 

6. Bad taste in your mouth

If you notice a salty or foul taste in your mouth, that could be pus, that is likely indicating you may have an infection and you should contact your dentist.

Regular dental care can help prevent tooth infections

The best way to deal with a painful dental infection is to avoid getting one in the first place. Getting regular dental cleanings and good hygiene cab help get rid of a lot of the plaque that can cause tooth decay. Regular dental cleanings also allow your hygienist to spot any potential problems like small cracks or cavities where bacteria could enter the tooth to cause an infection. Keeping up a good oral hygiene routine at home will also help lower your risk of getting a dental infection.

If the cost of routine dental care is too high for you, enrolling in dental insurance can  help cover the cost. 

This is not dental care advice and should not be substituted for regular consultation with your dentist. If you have any concerns about your dental health, please contact your dentist's office.

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  1. https://www.cdc.gov/healthywater/hygiene/disease/dental\_caries.html, 2016

  2. https://www.mouthhealthy.org/en/az-topics/a/abscess, accessed September 2020

  3. https://www.cdc.gov/oralhealth/conditions/periodontal-disease.html, 2013

  4. https://www.mayoclinic.org/diseases-conditions/periodontitis/symptoms-causes/syc-20354473, 2020

  5. https://www.mayoclinic.org/diseases-conditions/tooth-abscess/symptoms-causes/syc-20350901, 2019

  6. https://www.mayoclinic.org/diseases-conditions/tooth-abscess/symptoms-causes/syc-20350901, 2019

  7. https://my.clevelandclinic.org/health/articles/21199-lymphatic-system, 2020

  8. https://www.mayoclinic.org/diseases-conditions/swollen-lymph-nodes/symptoms-causes/syc-20353902, 2019


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