Gums usually hurt because they are inflamed, and the most common cause is gingivitis: plaque at the gum line irritates the tissue, making it red, swollen, tender and prone to bleeding. Brushing too hard, mouth sores, hormonal changes, a partly erupted wisdom tooth, or an infection such as a gum abscess can also cause gum pain.
Why do my gums hurt? The common causes
| Cause | What it usually feels or looks like | Where |
|---|---|---|
| Gingivitis | Tender, red, puffy gums that bleed when you brush or floss | Along the gum line, often in several places |
| Periodontitis | Gums pulling away from teeth, loose or sensitive teeth, pain when chewing, persistent bad breath | Around affected teeth |
| Brushing too hard or hard bristles | Soreness after brushing, gums wearing back | Areas you brush hardest |
| Canker sore | A small, painful round sore with a pale center and red edge | On the gum or inside the cheek or lip |
| Hormonal changes | Swollen, tender gums that bleed more easily | Throughout the mouth |
| Pericoronitis (wisdom tooth) | Swollen, sore gum flap over a back tooth, bad taste, pain when swallowing | Very back of the mouth |
| Gum (periodontal) abscess | A swollen, pimple-like bump, throbbing pain, sometimes pus | One spot next to a tooth |
| Braces or dentures | Soreness where wires, brackets or a denture rub; plaque buildup around brackets | Where the appliance sits |
Gingivitis and gum disease
Gum disease is an infection of the tissues that hold your teeth in place. It usually starts when plaque, a sticky film of bacteria, builds up along the gum line. The National Institute of Dental and Craniofacial Research (NIDCR) lists red, swollen, tender or bleeding gums as its early signs.
Gingivitis is the mild, early stage. Mayo Clinic describes healthy gums as firm, pale pink and fitted tightly around the teeth; with gingivitis they turn puffy, dark red, tender, and bleed easily. It does not cause bone loss and can be reversed. If it is not treated, it can progress to periodontitis, where gums pull away from the teeth, teeth can loosen, and chewing can hurt. See our full guides to gum disease and bleeding gums.
Smoking is the biggest risk factor for gum disease, according to NIDCR, and it can make treatment less successful. Diabetes, some medications, hormonal changes and genetics also raise the risk.
My gums hurt after brushing
Soreness right after brushing often means you are pressing too hard or using a brush with stiff bristles. Over time, aggressive brushing can wear the gums back, leaving the roots exposed and sensitive. A soft-bristled brush, light pressure and small circular strokes are gentler. Our article on receding gums covers what happens when gums pull back.
Gums can also feel sore for a few days when you start flossing after a long break. That tenderness usually settles as the inflammation goes down. Bleeding or pain that lasts longer than a couple of weeks is worth getting checked.
Mouth sores on the gums
Canker sores are small, shallow ulcers that can form on the gums as well as inside the cheeks and lips. They are not contagious, but they can be very painful, especially when eating acidic or spicy foods. Most heal on their own within a week or two. A sore that does not heal within about two weeks should be looked at by a dentist or doctor.
Hormonal changes
Hormones affect how gums respond to plaque. Pregnancy and menopause are common times for swollen, tender gums, and some people notice sore gums around their period. The underlying trigger is still plaque, so good daily cleaning and regular dental visits matter even more during these times.
Pain in the back of the gums
Pain at the very back of the mouth, behind the last molar, is often linked to a wisdom tooth. When a wisdom tooth only partly breaks through, a flap of gum can cover part of it. Food and bacteria get trapped under the flap and the gum becomes inflamed or infected. This is called pericoronitis.
Cleveland Clinic notes that it usually affects the lower wisdom teeth. Symptoms range from mild soreness and bad breath to pus, facial swelling, pain when swallowing, and difficulty opening the jaw. Untreated pericoronitis can become serious, so prompt dental care is important.
One painful, swollen spot: a gum abscess
A gum (periodontal) abscess is a pocket of pus in the gum, usually next to a tooth. It often looks like a swollen pimple or boil on the gum and can cause throbbing pain that spreads toward the ear, jaw or neck. Cleveland Clinic lists gum disease as the most common cause. An abscess does not go away on its own: it needs to be drained and treated by a dentist. Left untreated, the infection can spread to the jaw and to the soft tissues of the face and neck. Our tooth abscess guide explains how the different types differ.
Braces, dentures and other appliances
Braces make it harder to clean along the gum line, and plaque that collects around brackets and wires can make gums swollen and sore. A denture that no longer fits can rub and cause sore spots. Your orthodontist or dentist can adjust an appliance that is causing pain.
Other, less common causes
Gum pain can also come from tobacco use, food allergies or irritation from a new toothpaste or mouthwash, vitamin deficiencies, and, rarely, oral cancer. A red or white patch, a lump, or a sore that does not heal within about two weeks should always be checked by a dentist or doctor.
Bad gums: what healthy gums look like
Healthy gums are firm, pale pink, fit snugly around each tooth, and do not bleed when you brush or floss. Gums that are dark red, puffy, shiny, tender, bleeding or pulling away from the teeth are signs of inflammation. Gum disease can also develop without pain, which is why dentists measure the gum pockets around teeth at check-ups.
When to see a dentist
Book a dental visit if:
- Your gums still hurt or bleed after about two weeks of gentle brushing and daily cleaning between teeth.
- Your gums are pulling away from your teeth, or a tooth feels loose.
- You have persistent bad breath or a bad taste.
- A sore on your gum has not healed within two weeks.
Get care promptly (same day if you can) if:
- You have a swollen, painful bump on your gum or pus around a tooth.
- Gum pain comes with fever, facial or neck swelling, or swollen glands.
- You have trouble swallowing or opening your mouth.
If you cannot reach a dentist and have facial swelling with fever, trouble breathing or trouble swallowing, go to an emergency room.
Frequently asked questions
Why do my gums hurt all of a sudden?
Sudden gum pain often comes from something local: a bit of food such as a popcorn hull stuck under the gum, a canker sore, brushing too hard, or a new flare of gingivitis. Pain with swelling in one spot can be an abscess, and pain at the back of the mouth can be a wisdom tooth. Pain that lasts more than a few days needs a dental check.
Can gingivitis make your gums hurt?
Yes. Gingivitis makes gums inflamed, so they can feel tender or sore, especially when you brush, floss or eat. Many people with gingivitis have little or no pain, though, and notice bleeding first. Gingivitis is reversible with thorough daily cleaning and a professional cleaning.
Why do my gums hurt in one spot?
Pain in one spot can come from trapped food, a canker sore, irritation from a broken filling or appliance, or a gum abscess. An abscess usually looks like a swollen, pimple-like bump and may throb. Because an abscess is an infection that needs a dentist to treat it, a painful lump on the gum should be checked promptly.
Why do my gums hurt at the back of my mouth?
Pain behind the last molars is often caused by a wisdom tooth that has only partly come through. Food and bacteria trapped under the gum flap can cause inflammation and infection, called pericoronitis. Symptoms can include swelling, a bad taste, and pain when swallowing or opening the mouth, so it is worth seeing a dentist.
Is gum pain a dental emergency?
Usually not, but some signs need prompt care: facial or neck swelling, fever, pus, a swollen bump on the gum, or difficulty swallowing or opening your mouth. These can mean an infection that may spread. Mild soreness that improves with gentle cleaning over a few days is less urgent, but persistent pain should still be checked.
