Wisdom tooth pain is most often caused by a third molar that is coming in without enough room, trapping food and bacteria under the gum and inflaming it. Mild aching during eruption can settle on its own, but swelling, a bad taste, trouble opening your mouth or fever means you should call a dentist the same day.
Key Takeaways
- Wisdom teeth are the third molars, and according to the American Dental Association they usually appear between ages 17 and 21.
- An impacted wisdom tooth is trapped in the jaw or under the gum because there is not enough room for it to come in properly.
- Pericoronitis, an infection of the gum flap over a partly erupted wisdom tooth, is one of the most common causes of wisdom tooth pain and swelling.
- Home care can ease discomfort for a short time, but it does not treat an infection or an impacted tooth.
- Swelling that spreads to the neck or eye, or that makes breathing or swallowing hard, is a medical emergency: call 911 or go to the hospital.
What causes wisdom tooth pain?
Wisdom tooth pain is pain at the very back of the jaw, behind the last molar, that comes from a wisdom tooth or the gum and bone around it. It can feel like a dull ache, a throbbing that spreads to the ear or jaw joint, or a sharp pain when you bite.
Wisdom teeth are the last teeth to come in. When there is enough space and they grow straight, the ADA notes they can help with chewing and that some discomfort as they emerge is normal. Problems start when the jaw is too crowded, the tooth is angled, or the gum only partly opens over it.
Common causes of wisdom tooth pain include:
- Eruption: pressure and tender gums as the tooth pushes through, which usually comes and goes.
- Pericoronitis: infection and swelling of the gum flap over a partly erupted tooth.
- Decay: wisdom teeth are hard to brush, so cavities are common, in the wisdom tooth itself or the molar in front of it.
- Gum disease: food packing in around the back teeth can inflame the gum and bone.
- Pressure on the neighbouring tooth: an angled wisdom tooth can push against the root of the second molar.
- Cysts: less commonly, a fluid-filled sac can form around an impacted tooth and damage bone or roots.
Pain in this area is not always from the wisdom tooth. A cracked or decayed second molar, jaw joint (TMJ) problems, sinus pressure or an earache can feel similar, which is one reason an exam is needed before deciding what to do.
What is an impacted wisdom tooth?
An impacted wisdom tooth is one that cannot fully come into its normal position. The ADA describes impacted wisdom teeth as trapped in the jaw or under the gums. Impaction is usually described by the angle of the tooth and how much of it is covered.
| Type of impaction | What it means | Why it can cause problems |
|---|---|---|
| Soft tissue (partly erupted) | The crown is through the bone but partly covered by gum | The gum flap traps food and bacteria, which can lead to pericoronitis |
| Partial bony | Part of the tooth is still in the jawbone | Hard to clean; may press on the tooth in front |
| Full bony | The whole tooth is inside the bone | Often painless, but may be linked to cysts or damage to nearby roots |
| Mesioangular (tilted forward) | The tooth leans toward the second molar | Can cause decay or root damage on the second molar |
| Horizontal | The tooth lies on its side | Usually cannot erupt; can press on neighbouring roots |
An impacted wisdom tooth does not always hurt. Some stay quiet for decades and are simply monitored. Others cause no pain but still create problems the patient cannot feel, such as a cavity on the back of the second molar, which is why X-rays are part of the assessment.
Pericoronitis: when the gum over a wisdom tooth gets infected
Pericoronitis is inflammation and infection of the gum around the crown of a partly erupted tooth, most often a lower wisdom tooth. The NHS lists gum infection (pericoronitis) among the most common problems caused by wisdom teeth that do not have room to come through.
Typical signs include:
- red, swollen and tender gum behind the last molar;
- pain that may spread toward the ear, throat or jaw;
- a bad taste or discharge (pus) from the area;
- bad breath that brushing does not fix;
- pain when biting, especially if the upper wisdom tooth bites down on the swollen gum;
- difficulty opening your mouth fully (trismus);
- swollen glands under the jaw, or fever.
Pericoronitis can flare up and settle down again several times. Each flare is a reason to have the tooth checked, because repeated infection is one of the reasons dentists recommend wisdom tooth removal.
Treatment usually starts locally: your dentist may clean and flush under the gum flap and give you instructions for rinsing and cleaning the area at home. The ADA's guideline on antibiotics for dental pain and swelling recommends dental treatment and over-the-counter pain relief for most tooth-related infections, with antibiotics reserved for infections that are spreading or causing signs such as fever and malaise. Your dentist will decide whether you need one.
How to ease wisdom tooth pain at home
These steps can make you more comfortable while you arrange a dental visit. They do not cure an infection or an impacted tooth.
- Rinse with warm salt water. A gentle salt-water rinse, especially after eating, helps clear food from under the gum flap. Swish and spit; do not swallow.
- Keep the area clean. Brush the back teeth carefully with a soft brush, even if it is sore. Food left under the gum makes pericoronitis worse.
- Use a cold compress. A cold pack wrapped in a cloth on the outside of the cheek for short periods can reduce swelling and ache.
- Choose soft foods. Chew on the other side and avoid hard, crunchy or very hot foods.
- Consider an over-the-counter pain reliever. Ibuprofen or acetaminophen can ease dental pain for many people. Follow the package directions, and ask a pharmacist which option is safe for you, especially if you are pregnant, take other medications or have a medical condition such as kidney disease, stomach ulcers or asthma.
Things to avoid:
- Do not put aspirin or crushed tablets directly on the gum or tooth; the ADA advises against it.
- Do not apply heat to the outside of a swollen face.
- Do not try to cut or drain the gum yourself.
- Do not rely on leftover antibiotics from a previous prescription.
If the pain eases within a day or two and there is no swelling, you may be dealing with normal eruption discomfort. Still mention it at your next checkup. If it keeps coming back, or you notice swelling or a bad taste, call the office.
When wisdom tooth pain needs a dentist today, and when it needs a hospital
Most wisdom tooth pain is a dental office problem. A few situations are medical emergencies because infection from the lower back teeth can spread into the spaces of the neck and floor of the mouth.
| What you notice | What to do |
|---|---|
| Mild ache or pressure that comes and goes, no swelling | Book a regular visit and mention it |
| Sore, swollen gum behind the last molar; bad taste; pain when biting | Call the dental office today |
| Swelling of the cheek or jaw, difficulty opening your mouth, fever | Call the dental office today and say you have swelling |
| Swelling spreading toward the eye, down the neck or under the tongue | Call 911 or go to the Emergency Department |
| Difficulty breathing, swallowing or speaking; drooling; feeling very unwell | Call 911 |
| Unsure, or it is after hours | Call 811 to speak with a registered nurse |
In Truro, the Emergency Department at the Colchester East Hants Health Centre, 600 Abenaki Rd, is open 24 hours a day. If you go there for a spreading infection, you will still need a dental visit afterward to treat the tooth that caused it.
How a dentist assesses a painful wisdom tooth
A wisdom tooth assessment combines an exam with imaging.
- History: when the pain started, whether it has happened before, and whether you have had swelling, fever or trouble opening your mouth.
- Exam: your dentist looks at the gum flap, checks for pus, tests the molar in front, checks your bite and feels for swollen glands.
- X-rays: a digital X-ray, often a periapical or panoramic view, shows the angle of the tooth, the roots and the bone around it. Our guide to how digital X-rays work explains the process.
- 3D imaging when indicated: if the roots of a lower wisdom tooth appear close to the nerve that supplies feeling to the lip and chin, your dentist may recommend a 3D CBCT scan to plan more safely. CBCT is not needed for every wisdom tooth.
Your dentist will then explain what they found: normal eruption, pericoronitis, decay, or an impacted tooth that is likely to keep causing problems.
Does every painful wisdom tooth need to come out?
No. Wisdom tooth removal is a common procedure, but it is one option among several, and the decision depends on the tooth, your symptoms and the risks of surgery for you.
According to the ADA, dentists may recommend removal when there is pain, infection, cysts, tumours, damage to neighbouring teeth, gum disease or decay that cannot be treated. The NHS notes that wisdom teeth that are not causing problems are usually monitored rather than removed.
| Option | When it may fit |
|---|---|
| Monitoring | The tooth is healthy, has room or is fully buried without problems |
| Cleaning and local care | A single mild episode of pericoronitis |
| Filling | A small cavity in a wisdom tooth that can be reached and kept clean |
| Removal | Repeated infection, decay that cannot be fixed, damage to the second molar, a cyst, or ongoing pain |
A wisdom tooth may be removed at the practice or referred to an oral surgeon depending on complexity. A fully erupted upper wisdom tooth is often straightforward; a deeply impacted lower tooth near the nerve is more likely to be referred.
What recovery is like
Recovery depends on how complex the extraction is. The NHS notes that pain and swelling usually improve after one to two days but can last up to two weeks, and that most people return to normal activities quickly, while more complicated removals may need a few days off. Your dentist or surgeon will give you written aftercare instructions.
A dry socket, which the NHS describes as a painful condition that happens when the blood clot over the socket does not form properly or is dislodged, is the complication people most often worry about. Following aftercare advice about smoking, rinsing and drinking through straws lowers the risk. If pain gets worse a few days after an extraction instead of better, call the office.
Cost factors
The cost of wisdom tooth removal depends on how many teeth are involved, whether they are erupted or impacted, the imaging needed, the type of anaesthesia and whether a referral to a specialist is required. Your dentist can give you an estimate before treatment. For questions about the federal program, see our Canadian Dental Care Plan page and call to confirm current participation and billing.
Special situations
- Teens and young adults: wisdom teeth are often evaluated in the late teens, when the roots are still forming. Your dentist may suggest monitoring with periodic X-rays.
- Pregnancy: gum inflammation can flare during pregnancy. Tell the dental team you are pregnant; urgent infection should still be treated, and elective removal may be planned around the pregnancy.
- Older adults: wisdom teeth that have been quiet for years can still develop decay or gum problems. Keep them in mind at checkups.
- Medical conditions: diabetes, blood thinners, bone medications and other conditions can affect treatment planning. Bring an up-to-date medication list.
Getting help for wisdom tooth pain in Truro
Landmark Dental Care is a family general practice at 125 Queen St in downtown Truro, in a Victorian Queen Anne–style home. Our hours are Monday to Friday, 8:30am to 5:00pm, and we see patients from Truro, Bible Hill and across Colchester County.
If you call about wisdom tooth pain, it helps to say how long it has hurt, whether there is swelling or a bad taste, and whether you can open your mouth normally. That tells the team how soon you should be seen. Our general dentistry team handles routine wisdom tooth checks and X-rays, and our emergency dentistry service is there when it cannot wait.
Outside office hours, call 811 for advice from a registered nurse, and use 911 or the Colchester East Hants Health Centre Emergency Department for the red-flag symptoms above.
FAQ
How long does wisdom tooth pain last?
Discomfort from a wisdom tooth coming in often settles within a few days and may come back in waves. Pain that lasts longer than a couple of days, keeps returning or comes with swelling usually means infection or impaction and should be checked by a dentist.
Can wisdom tooth pain go away on its own?
Mild eruption pain can. An episode of pericoronitis may also calm down for a while, but it often comes back if the gum flap keeps trapping food, so a dental exam is still a good idea.
Why does my wisdom tooth pain spread to my ear?
The nerves that supply the back teeth and the ear are closely connected, so pain from a lower wisdom tooth is often felt in the ear, jaw joint or throat. Ear pain with a sore gum at the back of the mouth points toward the tooth, but your dentist or doctor can rule out other causes.
Should I go to the ER for wisdom teeth swelling?
Go to the emergency department or call 911 if swelling is spreading to your eye or neck, or if you have trouble breathing, swallowing or opening your mouth. Swelling that stays near the tooth is usually a same-day dental office visit.
Do I need antibiotics for wisdom tooth pain?
Not usually. Most wisdom tooth infections are treated by cleaning the area or treating or removing the tooth, and antibiotics are generally reserved for infections that are spreading or causing fever. Your dentist will decide based on the exam.
Next step
If your wisdom tooth is sore, swollen or keeps flaring up, call about wisdom tooth pain or swelling at 902-893-2919, or use our contact page to book a visit at 125 Queen St, Truro. We will assess the tooth and explain your options, including when treatment can be done here and when an oral surgeon referral makes sense.
References
- ADA MouthHealthy: Wisdom Teeth
- NHS: Wisdom tooth removal
- American Dental Association: Antibiotics for Dental Pain and Swelling Guideline
- ADA MouthHealthy: Dental Emergencies
- Nova Scotia Health: Colchester East Hants Health Centre
- Government of Nova Scotia: 811
This article provides general educational information and is not a diagnosis or a substitute for care from a dentist or other qualified health professional.
About this guide
This article was written and reviewed by the Landmark Dental Care Team at Landmark Dental Care, 125 Queen St, Truro, NS B2N 2B4. It is general patient education and is not a diagnosis or a substitute for an examination. If you have pain, swelling or a change in your mouth, call us at 902-893-2919 so a dentist can assess you.