What is a dental abscess?
A dental abscess is a collection of pus caused by a bacterial infection. Most often it starts inside a tooth whose nerve has died from deep decay, a crack or an old knock, and the pus gathers around the tip of the root. It can also start in the gum beside a tooth, where gum disease has left a deep pocket.
The usual signs are a throbbing pain that can spread to the ear, jaw or neck, a tooth that hurts to bite on, a bad taste in the mouth, and swelling of the gum or face. Sometimes the pain suddenly eases. That usually means the pus has found a way out, not that the infection has gone.
Why does the face swell?
The face swells when the infection spreads out of the tooth into the soft tissue around it. Upper teeth tend to swell the cheek, sometimes up to the eye. Lower teeth tend to swell along and under the jaw line, and swelling around the lower back teeth needs watching closely, because infection there can track down into the neck.
Wisdom teeth are a common cause. When one has only partly come through, food and bacteria get trapped under the flap of gum over it. The area swells, it hurts to swallow, and the jaw can feel stiff. If swallowing itself becomes difficult or your mouth will barely open, treat it as an emergency (see below).
Repeated swelling like this is one of the usual reasons for taking a wisdom tooth out, though a single episode does not always mean it has to go. How that decision is made is covered in a separate guide.
When is it an emergency?
Go to a hospital emergency department now if a dental swelling comes with any of these: difficulty breathing, difficulty swallowing, swelling under the tongue or the tongue being pushed up, drooling or a muffled voice, swelling spreading up towards the eye or down into the neck, being unable to open your mouth properly, a high fever, or feeling very unwell.
Do not wait for a dental appointment, and do not wait to see whether it settles overnight. A spreading infection needs hospital care, and breathing comes first. If breathing is difficult, call 108 for an ambulance.
If you are not sure, go anyway. Being checked and sent home is fine. Waiting too long is not.
What can you do while you wait to be seen?
Call the clinic and mention the swelling when you book. Until then, a painkiller taken exactly as the pack says can take the edge off the pain. If you are pregnant, have a medical condition or take other medicines, ask a pharmacist which one is safe for you.
Soft food that is neither very hot nor very cold, chewing on the other side and gentle brushing around the area all help. Keep drinking water, even if eating is difficult.
A few things make it worse. Do not put a hot pack or a hot water bottle on your face, because heat can draw the infection towards the skin and spread the swelling. Do not press, burst or cut the swelling yourself. Do not hold a tablet against the gum, as it can burn. And do not start antibiotics left over from an earlier illness or bought without a prescription, because the wrong medicine can quieten the symptoms while the infection carries on.
What does treatment usually involve?
Treatment has two parts: letting the pus out, and dealing with what caused it. Drainage relieves the pressure and is done under local anaesthetic, either through the tooth or through a small cut in the gum.
Then the source has to be treated, or the abscess tends to come back. If the tooth can be saved, that usually means root canal treatment. If it cannot, it is taken out. Which of these suits your tooth is decided after an examination and an X-ray.
Antibiotics are not always needed. They help when the infection is spreading or you have a fever, but on their own they do not cure an abscess, because the source is still there. When they are needed, the dentist prescribes them.
Who sees this at STHIRA?
Abscess drainage is done by Dr Bhargav Kuchu, an oral and maxillofacial surgeon. It is one of the procedures done at the clinic under local anaesthetic, and you go home the same day.
If your gum or face is swelling, call or message the clinic and say so straight away. If any of the emergency signs above are there, go to a hospital instead.
Drainage of an abscess is one of the procedures described on our page about minor oral surgery at the clinic.
Common questions
When is a swollen face from a tooth an emergency?
When it comes with difficulty breathing or swallowing, swelling moving towards the eye or into the neck, trouble opening the mouth, a high fever or feeling very unwell. Any of those means a hospital emergency department, not a dental appointment.
Will antibiotics alone get rid of a dental abscess?
No. They can help control a spreading infection, but the pus still has to be drained and the tooth or gum treated, or the infection usually returns.
The abscess burst and the pain has eased. Do I still need to be seen?
Yes. Releasing the pressure eases the pain, but the infection and its cause are still there. It usually flares up again unless the tooth is treated.
Can a wisdom tooth cause swelling of the face?
Yes. Infection under the gum over a partly erupted wisdom tooth is a common cause of swelling at the back of the jaw, often with pain on swallowing and some stiffness when opening. If swallowing or breathing becomes difficult, your mouth will barely open, or the swelling spreads towards the eye or into the neck, go to a hospital emergency department.