Why a partly erupted tooth keeps getting infected
A wisdom tooth that is still coming through leaves a flap of gum lying over part of its crown. Underneath is a pocket that a toothbrush cannot reach. Food, plaque and bacteria collect there, and the gum becomes inflamed and then infected.
It is most common in the lower wisdom teeth, in the late teens and twenties, when those teeth are erupting. The upper tooth makes it worse: when it bites down on the swollen flap it bruises it, and the flare feeds itself.
That is why the problem keeps coming back. The infection settles and the flap stays in place, and the next trapped meal starts it again. The wisdom tooth pain page covers the other causes of pain at the back of the mouth.
What a flare feels like
A sore, red, puffy gum behind the last lower tooth, tender to touch and worse when you bite. A bad taste or breath, and sometimes pus that can be pressed out from under the flap.
Pain that can spread to the ear, throat or the side of the jaw, discomfort when swallowing, and a jaw that opens less than usual. A few lymph glands under the jaw can feel tender.
A mild flare may be little more than soreness and a bad taste for a few days. A severe one brings facial swelling, a fever and a mouth that will not open properly.
When it needs same-day care
Treat these as same-day problems: swelling that spreads into the cheek or under the jaw, difficulty opening your mouth or swallowing, or a fever. The infection can track into the spaces of the neck.
If breathing or swallowing is affected, or the swelling is spreading into the neck, go to a hospital emergency department and do not wait for a dental appointment.
Do not put heat on a swollen face, and do not take leftover antibiotics. They do not replace drainage and a proper exam. Face swelling due to tooth infection explains why this one is urgent.
How it is treated, and what you can do meanwhile
The dentist examines the area, usually takes an X-ray to see the angle of the tooth, and cleans out the space beneath the flap with an irrigating syringe. This is the part that works. Antibiotics are used only when the infection is spreading or you are unwell with it, and only on a dentist's advice.
Until you are seen, rinse with warm salt water several times a day and keep brushing the area gently with a small-headed brush. Avoiding it because it hurts is what lets the flare continue. Keep to soft food on the other side.
Paracetamol or ibuprofen can be taken as directed on the label. Avoid ibuprofen if you have stomach ulcers, kidney disease or asthma that it triggers, if you are on blood thinners, or if you are pregnant, unless your doctor says otherwise.
Whether the tooth should come out
A single mild flare in a tooth with room to come through can be managed with cleaning and watched. If the tooth has no space or sits at an angle, or flares come back repeatedly, removing it is the lasting fix. It depends on the tooth, the space, and how many flares you have had.
Some dentists trim the flap, but it tends to grow back, so it is mostly a short-term option. The full set of reasons is in do wisdom teeth need removing.
Removal is usually delayed until the acute infection has settled, because anaesthetic works less well in inflamed tissue. What to expect afterwards is in the recovery guide. Cost is on the tooth extraction cost page.
Common questions
Can pericoronitis go away on its own?
A mild flare often settles in a few days, which is why people wait. It usually returns because the gum flap that traps food is still there. Each flare carries a small risk of spreading, so repeated flares are a reason to have it assessed.
Is pericoronitis serious?
Usually it is a painful nuisance. It becomes serious when swelling spreads into the face or neck, or you cannot open your mouth or swallow properly, or have a fever. Those signs need same-day care, and a hospital emergency department if breathing or swallowing is affected.
Do I need antibiotics for pericoronitis?
Not always. Cleaning beneath the flap does most of the work in a mild flare. A dentist may prescribe antibiotics when the infection is spreading or you have a fever. Do not use leftover tablets, because they cannot replace proper cleaning and examination.
What helps pericoronitis at home?
Warm salt water rinses several times a day, gentle brushing of the area with a small brush, soft food on the other side, and paracetamol or ibuprofen as directed on the label. It is a holding measure until the area is properly cleaned by a dentist.
Does pericoronitis always mean the wisdom tooth must be removed?
No. A first or mild flare with a tooth that has space to come through can be managed and watched. Removal is advised when flares recur, the tooth is angled or blocked, or it is damaging the tooth in front.
About this page
This page is general information, not a diagnosis or a quotation. Prices are prevailing Lucknow market ranges. Your own treatment and cost are determined after an examination. For questions about your own case, call +91 83036 12717.