Wisdom tooth infection: What are causes, symptoms and treatment?

Getting wisdom teeth is uncomfortable in even the best of circumstances, but when they become infected, discomfort quickly turns into throbbing pain. The location of wisdom teeth in the back of the mouth makes them susceptible to infection, as does the fact that they often come in partially impacted—food easily gets stuck between the tooth and soft tissues and it’s difficult to brush or floss away.

When a wisdom tooth is infected, it’s important to get prompt treatment, as infection can spread to other parts of the body. During your appointment, dentist will clean the area surrounding the tooth to clear away food debris and bacteria, then prescribe a course of oral antibiotics. Once the infection has resolved, you can return to dental office to have your wisdom tooth extracted.

What are wisdom teeth? 

Your wisdom teeth are molars. They’re the large teeth at the back of your mouth, sometimes called the third molars. They’re the last teeth to grow in. Most people get wisdom teeth between the ages of 17 and 25.

Like other teeth, a wisdom tooth can:

  • decay
  • get a cavity
  • become impacted
  • get stuck below or in the gumline

If you have a wisdom tooth infection, you’ll need treatment from a dentist. But not all pain is the result of a tooth infection.

Causes of Wisdom Tooth Infection

There are several possible causes of infection in a wisdom tooth or where the tooth once was. These include:

An impacted wisdom tooth

Impaction happens when a person’s jaw has insufficient room for a wisdom tooth to erupt, in a situation referred to as ‘tooth crowding’.

Wisdom teeth may only emerge partially from the gum line or they can become trapped beneath it.

Either way, this can lead to inflammation of the gums and infection around the wisdom teeth. Sometimes soft tissue forms over the partially erupted wisdom tooth and is known as an operculum.

An operculum isn’t always good for your mouth because it tends to trap food particles causing bacteria to thrive. This, in turn, causes an infection which is often followed by an abscess that forms beneath the operculum. If the abscess isn’t treated, the infection spreads and progresses into pericoronitis. In severe cases, this can be extremely painful leaving the patient to call for an emergency dentist.


A cavity in a wisdom tooth can also be the cause of infection. Because wisdom teeth are located at the very back of the mouth they are difficult to reach with your toothbrush. Flossing wisdom teeth can be even more difficult. As a result, these teeth are vulnerable to decay.

Wisdom tooth extraction

 Wisdom tooth removal is a common procedure to pre-empt problems caused by teeth that are struggling to erupt or get stuck. Infection can sometimes occur after wisdom teeth removal.

Continued discomfort and/or swelling after the first 2- or 3-days following wisdom tooth removal is often a good indicator that you have an infection. You may experience a yellow discharge from the infected socket which leaves a nasty taste in your mouth or you may feel sick or develop a fever.

Symptoms of an Infected Wisdom Tooth

The first sign of an infected wisdom tooth is usually pain at the back of your mouth, either in or around the wisdom tooth or in the jaw. If it’s not immediately treated, the pain might spread into the throat and neck as well as all over the jaw. You might also have a sore throat, and the lymph glands just under the jaw may become swollen as the clusters of white blood cells they contain fight the invading bacterial infection.

Your face and jaw may also swell at this time, causing you some alarm and making it difficult to eat, but it’s a sure sign of an infected wisdom tooth. Many people with an infected wisdom tooth also notice a bad taste or smell in their mouth that just won’t go away, and again, this is a result of the bacteria that have taken hold in or around the wisdom tooth and the odours they give off.


Sometimes an infection in the wisdom teeth can lead to other health problems. These include:

  • A cyst – This is a fluid sac that forms near to a tooth that can be caused by impacted wisdom teeth or infection. Cysts can affect the roots of adjacent teeth and may even weaken or damage the jaw.
  • Severe or recurrent infections – Chronic infection from wisdom teeth can travel through the mouth, jaw, and respiratory tract which in rare cases can enter the bloodstream. This causes a serious health condition known as sepsis. Many dentists remove wisdom teeth at the first sign of trouble to prevent recurrent infections.

Home remedies

Home remedies

Home remedies can’t treat a wisdom tooth infection. However, some simple treatments may give you temporary relief from the pain and discomfort. Try these remedies if you have to wait to see your dentist.

  • Salt water rinse.Mix salt in warm or cold drinking water. Swish it around your mouth a few times and spit out. The salt helps to temporarily slow down some of the bacteria.
  • Hydrogen peroxide.Dilute hydrogen peroxide in equal parts drinking water. Use this solution as a mouthwash. Hydrogen peroxide is antibacterial and will help remove some of the surface bacteria around the infection.
  • Cold compress.Place an ice pack or a cold cloth compress on the outside of your cheek, over the infected area. The cold helps to soothe swelling and inflammation.
  • Clove oil.Cloves contain natural antibacterial oils. Use a cotton swab to dab clove oil directly onto your wisdom tooth. Repeat a few times to help ease swelling and pain.
  • Over-the-counter pain medication.Pain medication and numbing gels can help you cope with the pain and get a good night’s sleep before your dentist appointment. Pain medications and benzocaine numbing gels can help relieve minor tooth pain.

When to see a doctor?

When to see a doctor

Call your dentist and make an appointment if you have any pain or discomfort in or around a wisdom tooth. This area can be difficult to see. You’ll likely need a dental exam and an X-ray scan to find out what’s causing the pain.

Don’t ignore any teeth, gum, or jaw symptoms such as:

  • pain or sensitivity
  • tender or swollen gums
  • red or bleeding gums
  • white fluid or oozing around teeth
  • bad breath
  • bad taste in your mouth
  • jaw pain
  • jaw swelling
  • stiff jaw
  • difficulty breathing, opening your mouth, or speaking

You may also have a fever, chills, nausea, or headache pain because of a wisdom tooth infection.


Treatment for a wisdom tooth infection may involve:

  • medication to treat the tooth
  • dental work to repair it
  • surgery for tooth removal

Your dentist will examine your teeth and take an X-ray of the area. This will help determine what kind of treatment is best for your tooth.



You’ll need to take antibiotics to clear up an infection in a wisdom tooth. You may need to take this at least a week before having the affected tooth repaired or removed. Antibiotics help to heal an infected tooth and prevent bacteria from spreading.

Your dentist or doctor may prescribe antibiotics such as:

  • penicillin
  • amoxicillin
  • metronidazole
  • clindamycin
  • erythromycin

Your dentist may also recommend pain medication before and after wisdom tooth infection, including:

  • ibuprofen
  • lornoxicam
  • acetaminophen
  • aspirin



Once the infection is cleared up, you’ll need to see your dentist again to repair or remove the tooth. Fixing a cavity in a wisdom tooth is similar to patching up other teeth. You may need a filling or crown.

Your dentist may also file down the top or sides of the tooth. This removes rough or bumpy edges that can trap food and bacteria. It also helps to make the tooth slightly smaller if there’s crowding.



If your wisdom tooth is damaged, your dentist may completely or partly remove it. You may need dental surgery for an impacted wisdom tooth infection. Other impacted wisdom teeth may also be removed. This helps to prevent future infections.

Your dentist may remove gum tissue from the top of an impacted wisdom tooth to help it grow through. Another dental procedure removes only the top part of a wisdom tooth. This is called a coronectomy. This helps to protect the tooth roots, nerves, and the jawbone around the tooth.

Pulling a wisdom tooth can be complicated. You’ll need local anesthesia by an injection in the area, or general anesthesia. The procedure may take 20 minutes or longer. Your dentist may need to section the tooth and remove it in pieces. This helps to avoid injury to the nerves and jawbone.

Possible side effects and risks after wisdom tooth removal surgery include:

  • bleeding
  • infection
  • numbness in your tongue, lower lip, or chin
  • jawbone weakness

An infection in the mouth can happen two weeks or even up to two months after getting a wisdom tooth removed. Let your dentist know about any symptoms. You may need another dose of antibiotics to treat it.

Care after surgery for removal of wisdom teeth

Your oral health professional will talk with you about how to care for your mouth after having a wisdom tooth taken out. Some general suggestions include:

  • Take pain-relieving medication if needed (and on advice from your oral health professional).
  • Hold warm salty water in your mouth. Do this after meals and no earlier than 24 hours after surgery.
  • Eat soft, easy-to-chew foods for the next few days.
  • Don’t smoke for 48 hours after the surgery.