A dental abscess is a pocket of pus that develops when there’s a severe infection from bacteria inside your tooth, at the gum-line, or in the jawbone. This is one of the most serious dental emergencies and if left untreated the infection can travel quickly to the surrounding areas of the face, neck and bloodstream. Knowing what causes a dental abscess and recognizing the risk factors can help you seek treatment sooner to keep your teeth healthy in the long term.

Below are the main reasons why a dental abscess can occur:

1. Deep Decay

Tooth decay is the most common reason for developing a apical abscess. The bacteria will eat away at the outer layers of the tooth.

Enamel/Dentin Loss

  • Bacteria living in the mouth will feed on the sugar in your diet. They produce acid which eats away at the enamel and dentin.

Pulp Damage

  • When the decay reaches the pulp inside your tooth the bacteria will begin to multiply in the blood vessels and nerves. This causes severe inflammation of the pulp.

Nerve Damage

  • The bacteria will cause the nerves to die (necrosis). As the infection builds up inside the root canal it has nowhere to go so will form an abscess at the tip of your root (apex).

2. Gum Disease

Gum disease is the main cause for developing a periodontal abscess.

Plaque Build Up

  • Not brushing your teeth properly will cause a build up of plaque. This turns to tartar.

Periodontal Pockets

  • Bacteria can cause chronic inflammation of the gums. This causes the gums to pull away from your teeth creating deep pockets.

Food/Bacteria Build Up

  • Food, tartar and bacteria will get stuck in the tight pockets. As the top of the pockets close or become inflamed the bacteria will begin to multiply in the tight pocket causing a periodontal abscess.

3. Trauma/Crack/Fracture

If your teeth have experienced trauma, sports injury or pressure they can become damaged allowing bacteria into your teeth.

Cracked Enamel

  • When your teeth are damaged they can crack or chip. This creates micro fissures in the dentin or pulp.

Trauma

  • If your teeth have been hit very hard even if the enamel is intact the blood vessels to the tip of the root can be damaged. This will cause the pulp inside your tooth to slowly die. Eventually it will become infected and cause a apical abscess.

Teeth Grinding

  • If you suffer from severe teeth grinding then your teeth will be under extreme pressure causing micro fractures. These can allow bacteria to become trapped.

4. Impacted Teeth

If your teeth don’t fully erupt then bacteria can easily become trapped.

Erupted Wisdom Teeth

  • Wisdom teeth often don’t have enough room to fully erupt. This means your gums will form a flap (operculum) over the crown of the tooth.

Severe Inflammation

  • Food will become trapped under the flap and bacteria will start to build up. This can cause severe inflammation . This can quickly cause an abscess to form.

Impacted Canines/ Molars

  • Any impacted teeth can cause inflammation of the surrounding tissue.

5. Damaged Fillings

Fillings are to protect and repair damaged teeth. However, old, damaged or incorrectly placed fillings can cause an abscess.

Damaged Fillings

  • Over time fillings can shrink, crack or leak. This will allow saliva and bacteria to get underneath.

Bacteria Under Crowns

  • If a crown becomes damaged or there’s decay around the edge of the crown then bacteria will become trapped deep in your natural teeth.

Failed Root Canal

  • If a root canal wasn’t done properly then there will be bacteria still present in the complex canals. This can cause them to multiply years later causing an abscess at the tip of your root.

6. High Sugar Diet

The way you look after your teeth daily can cause bacteria to build up.

Too Much Refined Sugar

  • Eating lots of sugary snacks, fizzy drinks, sticky sweets and simple carbohydrates will give cavity causing bacteria such as streptococcus mutants lots of food to feed on.

Not Brushing/Flossing

  • If you don’t brush your teeth daily or floss between your teeth then thick biofilm (plaque) can build up.

Dry Mouth

  • Saliva helps to wash away food and neutralize the bacteria. If you don’t have enough saliva then you’re more likely to get cavities and bacteria.

7. Illnesses

Your immune system protects you from infection. If you suffer from illnesses that affect your immune system you’ll be more likely to develop an abscess.

Diabetes

  • If you suffer from diabetes and aren’t controlling it then your white blood cells won’t work as well. You’ll have less healing in your body. This causes the bacteria in your gums to break down quickly meaning you’re much more likely to develop a severe periodontal abscess.

Suppressants

  • Taking suppressants such as steroids, chemo  can cause your body to not fight infection as well. This can cause small infections to become severe and painful abscesses.

Autoimmune/Chronic Illnesses

  • Suffering from illness such as HIV/AIDS or autoimmune conditions will weaken your immunity. This will cause you to get more infections.

How to Prevent a Dental Abscess

  • Brush your teeth thoroughly twice a day for 2 minutes using a soft bristle brush and fluoridated toothpaste.
  • Use floss, inter-dental brushes or a water floss to clean between your teeth daily.
  • Try to limit how much refined sugar, sticky sweets and acidic drinks you drink.
  • Wear a mouth guard whilst playing sport and a night-guard if you suffer from teeth grinding.
  • Attend to any small cavities, cracked fillings or bleeding gums.
  • Have professional check ups every 6 months. This will help you spot any issues early with x-rays.

FAQs

Will a dental abscess go away?

No, a dental abscess will never go away. Whilst the pain may stop if your nerve dies or there is drainage from the abscess the infection will still be in your bone/tooth. This means it will continue to spread until you seek treatment.

What is the difference between a apical and periodontal abscess?

A apical abscess is caused by an infection inside the nerve pulp of your tooth. This is usually caused by deep cavities or trauma. The infection will form at the tip of the root in your jawbone. A periodontal abscess is caused by an infection in your gums. This usually occurs due to severe gum disease.

Can a dental abscess cause problems with my health?

Yes, if left untreated the infection can cause problems in your face, neck, jawbone and bloodstream. This can cause serious conditions such as cellulitis, Ludwig’s angina or sepsis.

How can a dental abscess be treated?

To treat a dental abscess you need to remove the infection. This can be done by draining the infection, root canal, deep scaling or extracting the tooth.

Knowing what causes a dental abscess can help you prevent them. Whether they’re caused by deep cavities, severe gum disease, trauma or damaged fillings they are a serious medical issue. By working with your dentist to have regular check ups, looking after your teeth daily and attending to any small issues you’ll keep your teeth strong and free from painful infections.