Gum disease: bleeding, swelling, receding gums and treatment

Gums that bleed when you brush, red and swollen gums, or teeth that look longer than before: gum problems are very common, and they often cause no pain at first. This guide explains in simple words why gums become inflamed, how they are treated, and what you can do at home, based on the international classification of gum diseases and on the main published studies. It is for information only and does not replace an examination: every mouth is different.

Healthy gums and inflamed gums

Healthy gums are pink and firm, fit tightly around the teeth, and do not bleed with normal brushing.

Inflamed gums are red, swollen, sometimes shiny, and bleed easily when you brush or floss; they can also cause bad breath. Early inflammation is usually painless, which is why it is often ignored.

Why do gums become inflamed? Plaque and tartar

The main cause is plaque: a soft, sticky layer of bacteria that builds up on the teeth all day long, especially along the gum line and between the teeth. A toothbrush used properly removes it.

If plaque is not removed, it hardens with the minerals in saliva and turns into tartar (which many people call "calculus" or "scale"): a hard white, yellow or brown crust, often behind the lower front teeth. Tartar is rough and keeps plaque stuck against the gums. A toothbrush, floss or mouthwash cannot remove it: only a professional clean at the dentist can. See also our guide to scale and polish.

Bleeding gums: what does it mean?

Gums that bleed when you brush are usually a sign of inflammation. According to the 2017 international consensus on the classification of gum diseases, this bleeding is the main feature of gingivitis, and the gums can return to health after treatment (Chapple et al., 2018, PubMed).

A common mistake is to stop brushing the area that bleeds. The opposite is true: keep brushing gently and carefully, because removing plaque is what allows the gums to heal. Heavy bleeding, bleeding for no reason, or bleeding with fever, swelling or strong pain needs a check-up.

Swollen gums

General swelling of the gums around the teeth usually goes with the inflammation caused by plaque and tartar, and it normally goes down once the teeth are cleaned properly.

A localised, painful swelling, such as a small bubble on the gum, a swollen cheek, or pus, may be a sign of an abscess or an infection around a particular tooth, or around a wisdom tooth that is coming through (see the wisdom teeth guide): in that case, you need an examination without waiting.

Gingivitis and periodontitis: what is the difference?

• Gingivitis: a surface inflammation of the gums caused by plaque. It can be fully cured.
• Periodontitis: goes further, as the inflammation slowly destroys what holds the tooth in place, that is, the attachment of the gum and the bone around the root. If it is not treated, this destruction continues (Jervøe-Storm et al., 2024, PubMed), and at an advanced stage the teeth may start to move.

Even after treatment and once the condition is stable, people who have had periodontitis remain at higher risk of it coming back, and they need close follow-up (Chapple et al., 2018, PubMed).

Receding gums

Receding gums means that the gum edge moves back and part of the root is exposed: the tooth looks longer and may become sensitive to cold. Known causes include periodontitis, brushing too hard with a hard toothbrush, naturally thin gums, and sometimes the position of the tooth in the arch. Because the cause differs from one case to another, treatment starts with an examination to find the cause and stop it, before thinking about any repair.

Gum treatment at the dentist

1. Examination: the dentist looks for tartar, bleeding areas and tooth decay, and may measure the depth between the gum and the tooth or ask for an X-ray.
2. Scale and polish: tartar above the gum line is removed, often with an ultrasonic device, then the teeth are polished.
3. Deep cleaning under the gums if there is periodontitis: the root surface under the gum is cleaned, often over several sessions. This is the core of non-surgical treatment (Jervøe-Storm et al., 2024, PubMed).
4. Advice and follow-up: the dentist shows you where plaque stays and how to clean these areas, and suggests a check-up schedule that suits your situation.

Your gums may bleed during the session and for a few days afterwards, and temporary sensitivity may appear, especially to cold. If the sensitivity lasts or bothers you, talk to your dentist.

Caring for your gums at home

• Brush your teeth twice a day, for about two minutes, with a fluoride toothpaste, focusing on the gum line, using a soft toothbrush.
• Clean between your teeth every day, with floss or with an interdental brush in the size your dentist recommends. A Cochrane review concludes that floss or interdental brushes, used with a toothbrush, may reduce gum inflammation or plaque more than a toothbrush alone, and that interdental brushes may be more effective than floss; but the certainty of the evidence is low and the studies are short (Worthington et al., 2019, PubMed).
• Do not try to scrape off tartar yourself with a sharp tool: you could injure your gums.
• Do not take any medicine or use any medicated mouthwash without the advice of your dentist or pharmacist.

Factors that increase the risk of gum disease

• Smoking and diabetes: both are recognised as factors that make periodontitis worse (Jepsen et al., 2018, PubMed).
• Pregnancy: gums often bleed more during pregnancy; tell your dentist you are pregnant so they can decide with you on the right timing and treatment.
• Fixed braces: they trap plaque around the brackets. A systematic review found a temporary rise in some bacteria under the gums after the braces were fitted, which then returned to their usual level after a few months (Guo et al., 2017, PubMed). Teeth are not moved on inflamed gums: your gums must be healthy before braces and stay healthy throughout treatment.

When should you seek help quickly?

• Heavy bleeding, or bleeding that appears for no reason;
• painful swelling of the gum or cheek, or pus, or fever;
• a tooth that is loose or changes position;
• bad breath that persists despite good cleaning.

If you have swelling that spreads quickly towards the neck, or difficulty breathing or swallowing, go to the emergency department straight away.

In practice

1. Gums that bleed are inflamed: keep brushing gently and ask for an examination.
2. Tartar does not come off with a toothbrush: only a professional clean at the dentist removes it.
3. Gingivitis can be cured; periodontitis can be stopped, and it needs lifelong follow-up.
4. Tell your dentist if you smoke, have diabetes or are pregnant.
5. Clean between your teeth every day.
6. Ask your dentist for a check-up schedule that suits your situation, rather than one fixed rule for everyone.

Frequently asked questions

Why do my gums bleed when I brush?

Usually because of inflammation caused by plaque and tartar along the gum line; keep brushing gently and ask for an examination, because removing plaque and tartar is what allows the gums to heal.

Can gingivitis be cured for good?

Yes, surface gingivitis can be cured by removing plaque and tartar and by cleaning well at home; periodontitis can be stopped, but it needs regular follow-up.

Do receding gums grow back?

They do not usually come back on their own; the first step is to find the cause and stop it, then your dentist will decide whether anything needs to be repaired.

How often should I have my teeth scaled?

There is no single rule for everyone: your dentist sets the schedule based on how quickly tartar builds up, the health of your gums, smoking, diabetes and any history of gum disease.

Is gum inflammation dangerous during pregnancy?

Gums often bleed more during pregnancy, and a gum check-up is helpful; tell your dentist you are pregnant so they can choose the right timing and treatment with you, in agreement with your doctor if needed.