How it develops
Plaque is a soft, sticky film of bacteria that forms on the teeth every day. Where it is left along the gum line, the gum becomes inflamed: red, swollen and quick to bleed. This is gingivitis. At this stage the bone is not affected, and the gum recovers once the plaque is removed regularly.
If the inflammation continues, it can spread below the gum. The fibres that attach the gum and ligament to the tooth break down, a pocket opens between gum and tooth, and the bone around the root is gradually lost. This is periodontitis. Teeth can become loose, drift apart and eventually be lost. According to the World Health Organization, severe periodontal disease is estimated to account for more than one billion cases worldwide.
From healthy gum to periodontitis
- Healthy. The gum fits snugly around the tooth and the bone reaches just below its neck. A periodontal probe slips only a little way into the groove.
- Gingivitis. The gum is swollen and bleeds easily; the bone is unchanged. This stage can be reversed.
- Periodontitis. The attachment breaks down, a deeper pocket forms and bone is lost around the root.
Simplified drawing, not to scale.
Signs to look for
- gums that bleed when you brush or clean between the teeth;
- red or swollen gums;
- bad breath or an unpleasant taste;
- gums that shrink back from the teeth;
- teeth that feel loose, move or change how they meet when you bite.
In its early stages gum disease often causes no pain at all, which is one reason regular check‑ups matter.
What raises the risk
- plaque that is not removed regularly, and tartar that forms from it;
- smoking and other tobacco use, one of the main risk factors named by the WHO;
- diabetes, especially when blood sugar is not well controlled;
- a family history of gum disease;
- hormonal changes, for example in pregnancy;
- some medicines that dry the mouth or make the gums overgrow.
How it is usually treated
Gingivitis is treated by removing plaque and tartar and improving daily cleaning. Periodontitis is treated in steps, as set out in the European Federation of Periodontology's clinical practice guideline:
Plaque control and risk factors. Instruction in cleaning the teeth and between them, removal of plaque and tartar above the gum, and help with risk factors such as smoking and diabetes.
Cleaning below the gum. Deep cleaning of the root surfaces inside the pockets, usually under local anaesthetic.
Further treatment where needed. Pockets that remain deep may be treated again, or with gum surgery.
Supportive care. Regular maintenance visits over the long term, with an interval set for each person's risk.
Prevention
Brush twice a day for about two minutes with a fluoride toothpaste, and spit rather than rinse afterwards. Clean between the teeth every day with interdental brushes or floss. Do not smoke. Keep to the check‑ups your dentist recommends. The same care protects the gum around dental implants and around wisdom teeth at the back of the mouth.
Questions patients ask
Is it normal for gums to bleed when I brush?
Bleeding when brushing or cleaning between the teeth is common, but it is not normal for healthy gums. It is often the earliest sign of gingivitis. Keep brushing gently and thoroughly, and mention it at your next dental check-up.
Can gum disease be reversed?
Gingivitis can be reversed with good plaque control and, if needed, a professional clean. In periodontitis, the bone and attachment already lost do not usually grow back, but the disease can be brought under control and kept stable with treatment and regular maintenance.
Does gum disease cause bad breath?
It can. Bacteria in plaque and in gum pockets produce unpleasant-smelling compounds. Bad breath has other causes too, so it is worth having it checked.
Is gum disease linked to other health problems?
Periodontitis is associated with diabetes, and the two affect each other: high blood sugar raises the risk of gum disease, and treating gum disease can help blood-sugar control. Links with heart disease and other conditions have also been reported.
How often should my gums be checked?
As often as your dentist recommends for you. The interval depends on your own risk, for example whether you smoke, have diabetes or have had gum disease before.
What this page rests on
This page rests on published guidance from the World Health Organization, the NHS and the European Federation of Periodontology, including its clinical practice guideline for treating periodontitis. It is general information: gum health can only be assessed at an examination.
General health information, not a diagnosis or a treatment recommendation for any individual.
Sources
- World Health Organization — Oral health fact sheet
- NHS — Gum disease
- European Federation of Periodontology — What is periodontitis?
- Sanz M, et al. (2020) — Treatment of stage I–III periodontitis: the EFP S3 level clinical practice guideline. J Clin Periodontol 47 Suppl 22
- Oral Health Foundation — Gum disease