Tooth Abscess: Pus on the Gum and When It Is Urgent

How urgent is it?

This information is for general guidance and does not replace an examination by a doctor.

Gum boil vs abscess: are they the same thing?

Gum boil is an everyday word for a gum abscess. People use it for swelling of the cheek or gum that comes from a bad tooth. At appointments we often use it ourselves, because everyone understands it. The medical name depends on what is happening in the tissues: it is either periostitis, that is, inflammation of the periosteum (the membrane covering the bone), or an abscess, a localised collection of pus. For you, the general rule matters more: a gum boil means the infection has already spread beyond the tooth.

Where the pus comes from

A tooth abscess most often develops like this. Deep caries reaches the nerve, and the nerve becomes inflamed and dies. Bacteria travel through the root canal to the tip of the root. In time a collection of pus forms there, in the bone. It presses on the surrounding tissues and causes throbbing pain. We describe the early signs of cavities you should not ignore in a separate article.

A dental abscess can also have other causes. In our practice, these are:

• gum disease with deep pockets, that is, gaps between the tooth and the gum;
• a wisdom tooth that has only partly erupted;
• an injury to the tooth or gum;
• radiotherapy or chemotherapy.

How a gum boil starts

First the tooth hurts, either dully or with a throbbing pain, and it is worse when you bite. Then other signs appear:

• redness and swelling of the gum, sometimes a bump with pus;
• a swollen cheek or jaw;
• an unpleasant taste in the mouth;
• sensitivity to hot and cold;
• difficulty opening the mouth;
• pain when chewing;
• a raised temperature;
• enlarged lymph nodes in the neck.

It can also be the other way round. A chronic tooth root abscess may hardly hurt if the pus finds a way out through a fistula, a thin channel to the surface of the gum. A person can live for years with a pimple on the gum that comes and goes. At appointments we often hear: I have an abscess on my gum, but it does not hurt, so it is not serious. But the bone around the root may be breaking down all this time.

Can a gum boil burst on its own?

It can. Pus sometimes breaks through the gum, and the pain drops sharply because the pressure in the infected area falls. It seems that the body has coped by itself. But this is not recovery: the source of the infection stays in the root, and after a while everything starts again. Never lance or squeeze the abscess yourself, as it is easy to push the infection deeper.

Tooth abscess: why it is dangerous

This is not just a swollen cheek. The main danger is where the infection can spread: into the deep spaces of the neck (layers of loose tissue between the muscles), towards the sinuses and, in rare cases, deeper. According to international studies, teeth are among the main sources of deep neck infections.

The share of dental causes differs between hospitals, but the conclusion is the same: you cannot leave this kind of infection untreated. According to international studies, Ludwig's angina spreads quickly and can block the airway. So if swelling under the tongue or on the neck is growing fast, we ask you not to come to the dental clinic but to call 112 straight away.

What can be mistaken for a gum boil

Other conditions can also cause swelling that looks like a tooth abscess, so we make the diagnosis after an examination and an X-ray, not from a photo on the internet.

Is a gum boil contagious?

Not in the usual sense. It is an infection from your own tooth, not a disease that spreads through the air or via cutlery and dishes. You do not need to isolate yourself from your family. But do not touch the pus or try to squeeze it out.

How a gum boil is treated at the dentist

The aim of treatment is to remove the pus and the source of the infection. The order is as follows.

At appointments we are often asked whether you can simply take a course of antibiotics and skip the dentist. In our practice, the swelling may go down after tablets, but the infected area in the root remains and the inflammation returns. According to international studies, the source of the infection must first be removed locally, and antibiotics are indicated when it has spread or there are general symptoms. That is why the pus must be drained first and the tooth treated.

Can you pull a tooth with an abscess, or can it be saved?

The tooth can often be saved. If the root and the surrounding bone allow it, we save the tooth: we clean the canals, seal them tightly and then restore the tooth with a filling or a crown. We extract the tooth when it is badly damaged or the infection does not clear after treatment.

How long does treatment for a gum boil take?

Relief after drainage usually comes quickly. Full tooth treatment can take several visits. The exact timing depends on the tooth and on how far the inflammation has spread, and we give it after the examination.

Where to go for help

If you have noticed pus on the gum or a swollen cheek, see a dentist the same day or the next. We carry out the examination and X-ray at Cristi Dent in Chișinău, find the tooth causing the problem and draw up a treatment plan. More on the oral surgery page.