What to check when your gums are swollen: the shape of the swelling, causes, and care at home and at the dentist

Swollen gums are mostly an inflammatory reaction to plaque and tartar, and the Korea Disease Control and Prevention Agency (KDCA, 질병관리청) lists gum swelling as a typical symptom of periodontal disease. If the whole gum is red and swollen and bleeds when you brush, gingivitis is the likely cause; if one spot bulges in a round shape, hurts when pressed or leaks pus, it may be a periodontal abscess, a pocket of pus inside the gum. Gum disease causes little pain until it spreads into an abscess, so swelling that goes down has not necessarily healed, and repeated swelling should be checked at a dental clinic.

Published 2026-11-08 · Updated 2026-11-08 · DentalStatics editorial team

Key facts

What gum swelling means	Gum swelling is a typical symptom of periodontal disease (source: KDCA National Health Information Portal)
Change in gum color	It is caused by inflammation and appears in both mild and severe periodontal disease (source: KDCA National Health Information Portal)
Pain and progression	Periodontal disease usually has no pain, and causes little pain unless it progresses to an abscess (source: KDCA National Health Information Portal)
Look of an acute periodontal abscess	The gum beside the root rises in an oval shape, and pus often comes out at the gum edge when pressed (source: Seoul National University Hospital Medical Information)
Changes after scaling	As swollen gums settle down, the teeth may look longer or feel loose (source: KDCA National Health Information Portal)

Why do gums swell?

When bacteria in the plaque that builds up along the border between tooth and gum produce toxins, the gum widens its blood vessels and gathers immune cells to fight them. Blood and fluid pool in the gum tissue, which turns red and puffy, and the swollen gum becomes fragile and bleeds with slight irritation.

The KDCA explains that hormonal changes such as puberty, menstruation and pregnancy, blood disorders such as diabetes and leukemia, and some blood pressure drugs, anticonvulsants, immunosuppressants and oral contraceptives can also affect the gums. With these factors, the same amount of plaque can cause more swelling.

The shape of the swelling depends on how long and how deeply the inflammation has been present. Swelling that appeared within a few days tends to be bright red, soft and quick to bleed, while long-standing inflammation can turn the gum dark red or make it thick and firm. The KDCA also describes a change in gum color as a sign of inflammation.

What can the shape of the swelling tell you?

The extent and shape of the swelling are clues that narrow down the cause. The groupings below are only a guide; an accurate diagnosis requires a gum pocket examination and X-rays.

Gums around several teeth evenly red and swollen, with bleeding when brushing: possibly plaque-related gingivitis
Gum beside one tooth bulging in a round shape, painful or pus-producing when pressed: possibly a periodontal abscess
A small pocket of pus on the gum near the root tip: possibly an abscess from inflammation on the nerve side
Swelling only around the last molar with discomfort opening the mouth: possibly inflammation around a partly erupted tooth
Gums becoming thick without pain and covering the teeth: possibly an effect of medication or hormones

What should you do at home when your gums are swollen?

Even if the swollen gum hurts, do not stop brushing. Use a soft toothbrush and gently clean along the gum line to reduce plaque. Move dental floss or interdental brushes slowly along the sides of the teeth without forcing them into the gum.

Avoid squeezing out pus by pressing the swollen spot with a finger or needle, or rubbing it with salt, because these can worsen the wound and infection. Even if oral gum medicine or mouthwash eases the swelling for a while, it comes back if the tartar that caused it remains, so think of home care as only limiting the damage until you can see a dentist.

How does a dentist treat swollen gums?

The dentist examines the color and shape of the gums, bleeding, gum pocket depth and tooth mobility, and checks the bone around the teeth with X-rays. For gingivitis, scaling and corrections to brushing technique reduce the swelling; if tartar lies deep under the gum, root planing is done to smooth the root surface.

For a periodontal abscess, the tartar and the source of inflammation are removed, and antibiotics are sometimes added when the pus is active. An acute abscess can improve quickly with treatment and medication, but if it becomes chronic and keeps returning, surgery to open the gum and remove inflamed tissue may be needed. When medication has thickened the gums, the prescribing doctor is consulted about whether the drug should be adjusted.

Which kinds of swelling need prompt care?

If you see signs that the swelling is spreading beyond the gum, get care right away instead of waiting for a regular checkup. If swelling grows fast enough to make breathing or swallowing difficult, go to an emergency room.

Swelling spreads to the cheek, under the jaw or below the eye
Fever, tiredness or a lump felt under the jaw
Difficulty opening the mouth or pain when swallowing
Pus keeps coming from the swollen spot
A tooth suddenly becomes loose or feels raised

Common myths and facts

Myth: Once the gum swelling goes down, it has healed

Gum disease can progress quietly, with pain and swelling coming and going. If the tartar that caused it remains, the gum swells again.

Myth: Rubbing a swollen gum with salt makes it go down

Rubbing a swollen gum can injure it and worsen the inflammation. What reduces swelling is removing plaque and tartar.

Frequently asked questions

My gums are swollen but not painful. Is that okay?

The KDCA explains that periodontal disease usually progresses without pain and causes little pain until it spreads into an abscess. Painless does not mean mild, so get checked if the swelling keeps returning. The bone around the teeth can shrink little by little even while the swelling comes and goes.

Why do my gums swell when I am tired?

When the body is worn out, its ability to keep gum inflammation in check also drops, so mild inflammation that was already there shows up as swelling. If your gums swell every time you are tired, it signals that inflammation and tartar are already present, so get scaling to reduce the cause. In busy periods, not skipping brushing and flossing before bed is the most realistic way to prevent swelling.

Can I take painkillers when my gums are swollen?

They may ease the pain for a while but do not remove the cause of the swelling. Even if the pain lessens after taking medicine, you still need dental care, and if you take other medicines or have a chronic condition, consult a pharmacist or doctor before choosing one.

My gums swelled up after scaling.

Right after the procedure the gums are sensitive and may swell or ache for a while. The KDCA advises getting additional treatment at the dentist if the gums swell or hurt after the procedure, so see the dentist again if the swelling stays the same after several days.

My swollen gums have become thick enough to cover my teeth.

Long-standing inflammation, or the effect of some medicines or hormonal changes on the gums, may be the cause. Bring a list of the medicines you take so the dentist can find the cause, and if a medicine seems to be involved, consult the doctor who prescribed it.

References

Korean version →