In short
Gums that bleed when you brush are inflamed, not normal. Gingivitis is reversible, periodontitis is not, and the pocket depths measured at a check-up tell you which one you have.
Emergency if: Go to emergency care now for swelling of the face or jaw with a fever, swelling under the tongue or in the neck, difficulty breathing, speaking or swallowing, a jaw that will barely open, or a swollen or painful eye with any change in vision. Infection spreading from a tooth can close the airway or track towards the eye, and both are measured in hours.
On your report
HbA1c, Fasting Glucose, CRP
On this page
01
Are bleeding gums normal?
No. Healthy gums do not bleed when they are brushed, and blood in the sink is a sign of inflammation at the gum margin rather than a sign of brushing too hard. CDC describes the mildest form of gum disease, gingivitis, as an inflammatory condition where the gums become red, swollen and may easily bleed. The bleeding is the gum's blood vessels responding to bacteria sitting along the tooth at the gum line. It is the earliest signal available, and it is also the one most people decide to ignore.
The instinct after seeing blood is to brush that area less. That makes it worse, because the bacterial film causing the inflammation is exactly what brushing removes. Gums that bleed for the first week of proper cleaning and then stop were telling you something true. Bleeding that settles means the inflammation at the gum margin has settled; it does not tell you whether bone has already been lost underneath, and only the probe and the X-ray described further down answer that. Gums that still bleed after two weeks of careful daily cleaning need a dental assessment rather than a change of toothpaste. The absence of bleeding is not proof on its own either: the probe reading and the X-ray are what say whether the bone under the gum is intact, which is why a check is worth having even when nothing bleeds.
This is not a rare problem. WHO estimates that severe periodontal diseases affect more than 1 billion cases worldwide, and describes the disease as characterised by bleeding or swollen gums, pain and sometimes bad breath, with the gum eventually coming away from the tooth and supporting bone so that teeth become loose and sometimes fall out. CDC reports that in national survey data collected between 2009 and 2014, about 4 in 10 US adults aged 30 years and older had mild, moderate or severe periodontitis, rising to about 60% of adults aged 65 and over.
02
Gingivitis or periodontitis: which one can still be undone?
Gingivitis can. Periodontitis cannot. CDC's position is explicit: gingivitis is a reversible condition, but untreated cases can progress to periodontitis, which cannot be undone, although it can be slowed down and managed with professional treatment. The line between the two is not how much the gums bleed. It is whether the inflammation has reached the bone and the fibres holding the tooth in its socket.
CDC defines periodontitis as a chronic inflammatory condition that leads to mild, moderate or severe destruction of the supporting tissues around teeth, and notes that it causes bone loss around the affected teeth. Bone that has gone does not grow back with better brushing. This is why the question a dentist is really answering at a check-up is not whether your gums are sore, but whether you have crossed that line, and if so, how far.
The symptoms CDC lists for the later stage are worth knowing because they arrive quietly: red or swollen gums, bleeding, gums receding so teeth look longer, teeth becoming loose, sensitivity, painful chewing, and a change in the way the teeth meet when you bite. CDC names periodontitis and tooth decay as the two leading causes of tooth loss. Someone whose bite has changed or whose teeth have started to drift has usually had the disease for years.
03
What are plaque and calculus, and why does brushing stop being enough?
Plaque is the soft bacterial film that forms on teeth continuously and comes off with a brush. Calculus, also called tartar, is what plaque becomes if it is left. NIDCR puts it simply: dental plaque, if not removed every day, can harden and form tartar, and only a professional cleaning by a dentist or dental hygienist can remove tartar. Plaque and tartar contain bacteria which trigger the inflammation that damages the gums and supporting tissues.
That hardening is why brushing alone stops working past a certain point. A brush cannot remove a mineralised deposit, and the deposit has a rough surface that holds fresh plaque against the gum and below it, where no brush reaches anyway. So the cleaning gets harder exactly where the disease is active. This is the mechanical reason a person who brushes conscientiously twice a day can still have progressing gum disease, and it is not a character failing.
It also explains why the interval between professional cleanings matters more for some people than others. Calculus forms faster in some mouths, around crowded or crooked teeth, and along the inside of the lower front teeth where saliva glands empty. CDC lists crooked teeth, smoking, diabetes, certain medicines, stress, genetics, hormonal changes and poor nutrition among the things that raise risk, alongside poor oral hygiene, and WHO names poor oral hygiene and tobacco use as the main risk factors. Hormonal changes are on that list, so gums that become sorer and bleed more easily during a pregnancy are a reason to be seen and cleaned rather than something to leave until after the birth.
04
How is it checked, and what do the numbers mean?
With a small ruler and an X-ray. NIDCR describes the examination: the dentist uses a tiny ruler called a probe to measure the spaces around the teeth, known as pockets. In a healthy mouth these measure between 1 and 3 millimetres, and deeper pockets can be a sign of periodontal disease. X-rays are taken to see whether there has been any bone loss as a result of gum disease. Bleeding when the probe is placed is recorded too, because a pocket that bleeds is an active one.
Depth alone does not tell the whole story, which is why a dentist also records attachment loss, meaning how far the gum's attachment has moved down the root. StatPearls describes staging periodontitis by the proportion of bone lost on the X-ray, from stage I at 15% or less, through stage II at 15% to 30% and stage III at 30% to 60%, to stage IV above 60%. It also describes grading the likely speed of progression by dividing the percentage of bone loss by the person's age, so that the same amount of damage means something different at 30 than at 70.
Ask for your numbers. A chart of pocket depths from today, kept and compared with the one taken in a year, answers the only question that matters between visits: is this stable or is it moving. A single reading of 5 millimetres at one tooth is a very different problem from readings of 5 to 7 millimetres across the whole mouth, and neither can be judged from how the gums feel.
05
The two-way street with diabetes, and the links to heart disease
These two links are not the same strength, and conflating them is the commonest mistake in writing about gums. The diabetes link runs in both directions and is well evidenced. WHO states that diabetes has been linked in a reciprocal way with the development and progression of periodontal disease. StatPearls describes diabetes worsening periodontitis through impaired wound healing, and periodontal disease in turn being linked to hyperglycaemia, impaired glucose tolerance and poor glycaemic control, so that each makes the other harder to manage.
The consequences are measurable. StatPearls notes that people with type 2 diabetes and severe periodontal disease have been reported to face a 3.2 times higher mortality risk than people who have diabetes but not periodontal disease, and that effective management of diabetes improves the outcomes of periodontal treatment. If you have diabetes, gum treatment is part of diabetes care, and if you have stubborn gum disease, a glucose check is a reasonable thing to ask for.
The heart link is weaker and belongs in a different category. StatPearls says research suggests a direct connection between the bacterial presence in periodontal disease and the development of atherosclerosis, but that a causal relationship has not yet been definitively established, with raised C-reactive protein, a key inflammation marker, as the proposed mechanism. That is an association. Treating gum disease is worth doing for the teeth, the bone and the diabetes evidence. Nobody should be told it is a treatment for heart disease, because that has not been shown.
06
What do scaling and root planing actually involve?
They are a deep clean below the gum line, done under local anaesthetic if needed and usually across more than one appointment. NIDCR describes scaling and root planing as a deep cleaning of the affected tooth, and CDC lists it as the main non-surgical treatment, alongside prescribed medicines and, in more advanced disease, surgical procedures. Scaling removes the deposits from the tooth and root surface; root planing smooths the root so that the gum can seal closely against it instead of against a rough, contaminated surface.
What happens afterwards is worth expecting in advance. StatPearls describes probing depths reducing as healing occurs, with a long junctional epithelium forming a close seal against the cleaned root. In practice that means the gums shrink slightly as the swelling settles, so teeth can look a little longer and gaps can appear between them, and the necks of the teeth are often sensitive to cold for some weeks. None of that is the treatment going wrong. It is inflamed tissue returning to its actual size.
The results are then re-measured, usually a couple of months later, and the pockets that have not responded are the ones that decide what comes next. Smoking is the single largest thing a person can change that affects that re-measurement, since CDC lists it among the main risk factors. Treatment stops the loss where it can; it does not rebuild what has already gone, and a dentist who says so is being accurate rather than pessimistic.
07
Brushing, flossing and mouthwash: what does the evidence actually support?
Brushing twice a day with a fluoride toothpaste is the foundation, and NIDCR pairs it with cleaning between the teeth. What the trials show about that second part is more modest than advertising suggests. A Cochrane review of home interdental cleaning found that flossing in addition to toothbrushing may reduce gingivitis in the short and medium term, though it is unclear whether it reduces plaque, and that interdental brushes may reduce both gingivitis and plaque in the short term. The reviewers were clear that the evidence was low to very low certainty and the effect sizes observed may not be clinically important.
The same review found wooden cleaning sticks may reduce bleeding sites but not plaque, rubber sticks the other way round, and oral irrigators showing a short-term gingivitis effect with no evidence of a difference in plaque. Read together, this does not say cleaning between the teeth is pointless. It says the trials were short, mostly in people whose gums were nearly healthy to begin with, and that the choice of device matters less than doing it at all.
Mouthwash is where expectations most need adjusting. A Cochrane review of chlorhexidine mouthrinse found high-quality evidence of a large reduction in plaque when used alongside normal brushing, and a reduction in gingivitis in people with mild inflammation that was not considered clinically relevant, with insufficient evidence to say what it does in moderate to severe gingivitis. Used for four weeks or longer it stains teeth, needing a professional scale and polish to remove, and can cause taste disturbance and soreness of the lining of the mouth, while the evidence on whether it increases calculus was inconclusive. It is a short course prescribed for a reason, not a daily habit, and it does not replace the brush.
08
When does a loose tooth or an abscess need care today?
A tooth that has become loose in an adult, with no injury to explain it, means the bone holding it has been lost or an infection is active around it. Either way it needs assessment within days, not at the next routine check. The same goes for gums that have started to recede visibly, a bite that has changed, or pus appearing at the gum margin when the area is pressed.
An abscess is a different pace. NHS guidance describes a dental abscess as causing intense toothache or gum pain, redness inside the mouth or on the face or jaw, sensitivity to hot and cold, a bad taste, difficulty opening the mouth, swollen glands in the neck and a swollen face or jaw, and states that it needs urgent treatment by a dentist and will not go away on its own. Antibiotics alone are not the treatment; the pus has to be drained, and the tooth then needs root canal treatment or removal.
The point where this stops being a dental problem and becomes an emergency is the airway and the eye. NHS guidance is to seek emergency help for difficulty breathing, speaking or swallowing, a swollen or painful eye or sudden trouble with eyesight, significant swelling in the mouth, or a jaw that will barely open. Swelling under the tongue or in the neck can close an airway, and infection from an upper tooth can track towards the eye. Neither waits until morning.
Gum problems: how urgent?
Routine — see a doctor
Book a dental appointment in the next few weeks for gums that bleed when you brush, gums that look red or puffy, persistent bad breath or a bad taste, or sensitivity at the necks of the teeth. Ask for pocket depths to be measured and recorded, and for an X-ray if the pockets are deeper than 3 millimetres, so you have a baseline to compare against next year. If you have diabetes, say so, because gum treatment and glucose control pull on each other.
Same-day — call promptly
Contact a dentist the same day for a tooth that has become loose without an injury, pus at the gum margin, a swollen face or jaw, a gum swelling that is growing, toothache that is keeping you awake or not settling with ordinary painkillers, or a bad taste with a fever. NHS guidance is that a dental abscess needs urgent treatment by a dentist and will not go away on its own: it needs draining, and a prescription for antibiotics alone is not the treatment. If no dentist can see you today, use an urgent dental service or a doctor rather than waiting for an appointment next week.
Emergency — act now
Go to emergency care now for swelling of the face or jaw with a fever, swelling under the tongue or in the neck, difficulty breathing, speaking or swallowing, a jaw that will barely open, or a swollen or painful eye with any change in vision. Infection spreading from a tooth can close the airway or track towards the eye, and both are measured in hours.
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Sources
- Oral health - WHO fact sheetwho.int
- About Periodontal (Gum) Disease - CDCcdc.gov
- Periodontal (Gum) Disease - National Institute of Dental and Craniofacial Research (NIH)nidcr.nih.gov
- Periodontal Disease - StatPearls, NCBI Bookshelfncbi.nlm.nih.gov
- Home use of devices for cleaning between the teeth, in addition to toothbrushing - Cochrane reviewcochrane.org
- Chlorhexidine mouthrinse to reduce gingivitis and plaque build-up - Cochrane reviewcochrane.org
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