A tooth abscess is a pocket of pus that's caused by a bacterial infection. The abscess can occur at different areas near the tooth for different reasons. A periapical (per-e-AP-ih-kul) abscess occurs at the tip of the root. A periodontal (per-e-o-DON-tul) abscess occurs in the gums at the side of a tooth root. The information here is about periapical abscesses.

A periapical tooth abscess usually occurs as a result of an untreated dental cavity, an injury or prior dental work. The resulting infection with irritation and swelling (inflammation) can cause an abscess at the tip of the root.

Dentists will treat a tooth abscess by draining it and getting rid of the infection. They may be able to save your tooth with a root canal treatment. But in some cases the tooth may need to be pulled. Leaving a tooth abscess untreated can lead to serious, even life-threatening, complications.

Periapical tooth abscess

Periapical tooth abscess

Bacteria can enter the innermost part of the tooth through either a deep cavity or a chip or crack in your tooth. The resulting infection and inflammation can cause an abscess at the tip of the root.


Signs and symptoms of a tooth abscess include:

  • Severe, constant, throbbing toothache that can spread to your jawbone, neck or ear
  • Pain or discomfort with hot and cold temperatures
  • Pain or discomfort with the pressure of chewing or biting
  • Fever
  • Swelling in your face, cheek or neck that may lead to difficulty breathing or swallowing
  • Tender, swollen lymph nodes under your jaw or in your neck
  • Foul odor in your mouth
  • Sudden rush of foul-smelling and foul-tasting, salty fluid in your mouth and pain relief, if the abscess ruptures

When to see a doctor

See your dentist promptly if you have any signs or symptoms of a tooth abscess.

If you have a fever and swelling in your face and you can't reach your dentist, go to an emergency room. Also go to the emergency room if you have trouble breathing or swallowing. These symptoms may indicate that the infection has spread deeper into your jaw, throat or neck or even to other areas of your body.


A periapical tooth abscess occurs when bacteria invade the dental pulp. The pulp is the innermost part of the tooth that contains blood vessels, nerves and connective tissue.

Bacteria enter through either a dental cavity or a chip or crack in the tooth and spread all the way down to the root. The bacterial infection can cause swelling and inflammation at the tip of the root.

Risk factors

These factors may increase your risk of a tooth abscess:

  • Poor dental habits and care. Not taking proper care of your teeth and gums — such as not brushing your teeth twice a day and not flossing — can increase your risk of dental problems. Problems may include tooth decay, gum disease, tooth abscess, and other dental and mouth complications.
  • A diet high in sugar. Frequently eating and drinking foods rich in sugar, such as sweets and sodas, can contribute to dental cavities and turn into a tooth abscess.
  • Dry mouth. Having a dry mouth can increase your risk of tooth decay. Dry mouth is often due to the side effect of certain medications or issues related to aging.


A tooth abscess won't go away without treatment. If the abscess ruptures, the pain may improve a lot, making you think that the problem has gone away — but you still need to get dental treatment.

If the abscess doesn't drain, the infection may spread to your jaw and to other areas of your head and neck. If the tooth is located near the maxillary sinus — two large spaces under your eyes and behind your cheeks — you can also develop an opening between the tooth abscess and the sinus. This can cause an infection in the sinus cavity. You might even develop sepsis — a life-threatening infection that spreads throughout your body.

If you have a weakened immune system and you leave a tooth abscess untreated, your risk of a spreading infection increases even more.


Avoiding tooth decay is essential to preventing a tooth abscess. Take good care of your teeth to avoid tooth decay:

  • Drink water that contains fluoride.
  • Brush your teeth for two minutes at least twice a day with a fluoride toothpaste.
  • Use dental floss or a water flosser to clean between your teeth on a daily basis.
  • Replace your toothbrush every 3 to 4 months, or whenever the bristles are frayed.
  • Eat healthy food, limiting sugary items and between-meal snacks.
  • Visit your dentist regularly for checkups and professional cleanings.
  • Consider using an antiseptic or a fluoride mouth rinse to add an extra layer of protection against tooth decay.

Jun 29, 2022

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