Swollen gum around a wisdom tooth: what helps, and will it go away?
Why it happens
Lower wisdom teeth often do not have room to come through fully. A flap of gum stays over part of the tooth, and food and plaque collect underneath where a toothbrush cannot reach. The gum becomes inflamed and infected. An upper wisdom tooth biting down on the swollen flap makes it worse.
Signs
- Pain and swelling of the gum behind the last molar, sometimes spreading to the ear or throat
- Pain on biting or difficulty opening the mouth fully
- A bad taste or pus from under the gum
- Swollen glands under the jaw; sometimes a fever
What helps at home
- Rinse with warm salt water (about half a teaspoon in a glass of warm water) several times a day, especially after meals.
- Clean the area gently with a soft or small-headed toothbrush. It will be sore, but keeping it clean is what lets it settle.
- Chew on the other side and choose soft food for a few days.
- Do not apply heat to the outside of the face, and do not take leftover antibiotics.
When it is urgent
Go to a hospital emergency department if the swelling spreads into the cheek, under the jaw or down the neck, if you cannot open your mouth more than about a finger’s width, if swallowing or breathing is difficult, or if you have a fever and feel unwell. These are signs of a spreading infection.
What the dentist will do
- Clean and flush out the area under the gum flap.
- Take an X-ray (usually a full-mouth OPG) to see the position of the wisdom tooth and its roots.
- Check whether the upper wisdom tooth is biting on the flap; if so, removing the upper tooth may be advised.
- Prescribe antibiotics only if the infection is spreading or you have a fever.
- Once the infection has settled, discuss whether the wisdom tooth should be removed.
Will it go away on its own?
The episode usually settles, but the cause does not. As long as the gum flap remains over the tooth, food will keep collecting there, and repeated episodes are common, often getting worse each time. A wisdom tooth that is causing repeated pericoronitis is one of the most common reasons removal is recommended. If the tooth is well positioned and expected to come through fully, the dentist may suggest waiting and keeping it clean.
Removal: what it involves and costs
An erupted wisdom tooth can often be removed as a simple extraction ($150 per tooth at Toothsmith, with the CHAS back-tooth extraction subsidy for cardholders). A tooth that is impacted needs surgical removal ($1,362.50 for one tooth or $2,343.50 for two at the same sitting), which is MediSave-claimable. See wisdom tooth removal and is wisdom tooth surgery fully covered by MediSave?
Frequently asked questions
How long does pericoronitis last?
A mild episode often settles in a few days to a week with cleaning and salt-water rinses. It frequently comes back, because the gum flap that traps food is still there.
Do I need antibiotics for a swollen wisdom tooth gum?
Not always. Cleaning under the gum is the main treatment. Antibiotics are used when the infection is spreading, there is a fever, or swelling extends beyond the gum.
Can the gum flap be removed instead of the tooth?
Sometimes the flap can be trimmed, but it often grows back if the tooth is not coming through fully. Removing the wisdom tooth is the more reliable long-term solution when episodes keep recurring.
Can I have the wisdom tooth removed while the gum is swollen?
Usually the infection is settled first, so that the anaesthetic works well and healing is smoother. Your dentist will advise on timing.
Questions about your teeth?
Book a check-up. You will hear what we find, the options and the fee before anything is done.