Can an Infected Root Canal Cause Bad Breath?

by | Mar 11, 2021 | General Dentistry, Root Canal

According to a newsroom fact sheet of the American Association of Endodontists, 25 million root canal procedures are performed every year. There is nothing traumatic or life-threatening about root canals, even though certain misconceptions and myths circulate regarding the treatment.
This therapy aims to eradicate the bacterial infection from a root canal and preserve the original tooth structure. During the operation, the inflamed and decayed pulp is extracted, and the tooth is disinfected, filled, and sealed to prevent further decay.
Although very rare, there is a possibility of infection if the treated tooth did not heal properly. It can happen after several months or years from the initial treatment. A severe root canal infection may extend to other teeth, gums, jaw, and facial tissues.

Have you heard about the persistent bad breath due to a root canal infection? It is a common identifying symptom to diagnose unsuccessful root canal treatments.

Today we will walk you through every information you should know to deal with a bad breath problem, starting from reasons to remedies and prevention methods.


Infected root canal cause bad breath


What is a root canal infection?

To understand the aftereffect of an endodontic treatment or root canal therapy, you should gather an in-and-out idea of the tooth’s structure.

The enamel is the white exterior layer of the tooth composed of calcium and phosphorus. Underneath would be the pulp — a network of nerves, connective tissue, and blood vessels. And in between the pulp and the enamel, there is a porous hard layer known as dentin.

When the soft substance in the pulp cavity gets inflamed or infected, a root canal treatment is performed to remove the pulp and stop the bacteria from spreading, resulting in a dental abscess.

The root canal is generally a safe procedure. However, there are some unsuccessful cases. As the American Association of Endodontists explains, the reasons behind a failed root canal attempt could be:

  • Not treating the narrow or curved canals properly
  • Delayed crown placement after the procedure
  • Failing to check salivary contamination inside the tooth after the restoration.

As a result, a new decay or a broken filling can expose the tooth to a new infection.


Root canal infection and bad breath

Root canal infections and chronic bad breath come hand-in-hand. If you experience a foul smell following a root canal therapy even after regular brushing and flossing, it’s a sign that the treatment has gone wrong. It could be because of a bacterial infection or the development of an abscess.

When the bacteria responsible for the condition starts spreading in the pulp chamber, it emits an unpleasant odor and causes a bitter taste in your mouth.

Another toxic consequence of an infected root canal is dental abscess. As the pulp material dries, it creates a pocket full of pus near the root. Swelling and inflammation of the gum and the jaw tissue are inevitable. Even worse, sometimes pus can ooze from the affected area, accompanied by a foul smell.


Other signs and symptoms of the infection

You will notice the following symptoms along with a bad breath if you have a root canal infection:

  • Acute and lingering teeth pain
  • Gum tenderness and swelling
    ]Tooth discoloration (dark brown, blue, or yellow)
  • Discomfort in warm and swollen tissue near the tooth
  • Intense pain while eating and sensitivity to hot and cold food or drinks


What are the other causes of bad breath?

Having bad breath doesn’t always mean you have an infection. Here are some other reasons.

  • If not brushed or appropriately flossed, bacteria from the plaque deposit between your teeth can cause oral malodor.
  • Infection or oral diseases such as tooth decay or gingivitis can be another reason.
  • When you eat foods with a pungent smell like onion, garlic, or spices, they are carried to your lungs through the bloodstream after digestion and emit an awful smell.
  • If you don’t drink enough water or don’t produce sufficient saliva flow in your mouth, it will lead to a condition called ‘dry mouth,’ resulting in a rotten breath.


How to avoid bad breath due to root canal infections

Your dentist will most probably suggest repeating the same procedure to treat the infection that causes bad breath.

The following steps are typically performed during the re-treatment:

  • Applying a numbing ointment followed by local anesthesia.
  • Creating a small opening on the tooth with a dental drill to reach the pulp cavities.
  • Cleaning out all the damaged pulp material from the infected area with a tool called files.
  • Removing the existing filling substance and thoroughly clean out the canals.
  • Using a dose of antibiotics to prevent the infection permanently.
  • After disinfecting the area, filling up the hole with a latex-based, rubbery filler called gutta-percha.
  • Sealing the top opening with a sealant like an amalgam to protect the treated tooth from saliva and further infection.


Preventing root canal infection and bad breath

Here are some ways for you to avoid infection after a root canal therapy and prevent getting a root canal done in the first place:

  • Don’t skip basic oral hygiene. Brush at least twice daily and floss once.
  • Avoid chewing on hard food like hard candy or ice cubes. A dental crack can give access to bacteria to the tooth root.
  • Cut down acidic beverages and citrus fruits that might wear the tooth enamel and provide sugar content for bacteria food.
  • Don’t miss dental appointments with your dentist for the final restoration process for sealing.
  • After the root canal treatment, use an antiseptic mouthwash and an OTC painkiller for a few days.
  • Visit your dentist as soon as you notice any sign of infection.
  • Get your teeth checked up at least twice a year for the general wellness of oral health.



Now that you know the key symptoms, you know exactly when to knock at the dentist’s office. The suggested precautionary measures will surely help to prevent such a disaster.

If you think it’s a dental infection, Laguna Vista Dental is open to help you ease the pain and repair the damaged teeth. We believe that extractions aren’t always a quick fix. Instead, we offer endodontic treatment to cure any concern regarding root canals. You may request an appointment with us today for a healthier smile!

Krystle Fenton

Krystle Fenton

Krystle Fenton is the owner and lead dentist at Laguna Vista Dental in Elk Grove, CA. Dr. She has earned a Bachelor of Science degree in Biology with a minor in Chemistry from Andrews University. She then went on to Loma Linda University School of Dentistry, where she graduated with honors and is a member of the prestigious Omicron Kappa Upsilon (OKU) National Dental Honor Society. Dr. Fenton is a member of the American Dental Association, California Dental Association, and Sacramento District Dental Society. In her time away from the office, Dr. Fenton enjoys spending time with friends and family, traveling, spending time outdoors and watching movies.

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