Dental Care Basics

Decay and gum disease both begin in the places a toothbrush does not reach, which is why the technique that works is unhurried and complete rather than forceful. Nearly all of what protects teeth over a lifetime is a short routine done twice a day and a check-up you keep even when nothing hurts.

Updated 2026-08-28Source: General preventive dentistry as described by the American Dental Association and NHS oral health guidance. Emergency criteria for dental infection follow conventional urgent-care triage.
The short versionBuildFigure
EmergencySpreading facial swelling, or swelling affecting the eye, swallowing or breathing
BrushingTwice a day, two minutes, soft bristles, gentle pressure
Between the teethOnce a day — a brush cannot reach those surfaces at all
Bleeding gumsA reason to clean more carefully, not less, and to be seen
Check-upsOn the interval your dentist sets, symptoms or not

The dental problem that is an emergency

Most dental trouble is a booking, and this part is not. A dental infection that has spread beyond the tooth can involve the tissues of the face, floor of the mouth and neck, and that progression can be fast. Go to an emergency department, not a dental waiting list, for any of the following.

SignResponse
Facial swelling that is visibly spreading, or that has come up quicklyEmergency care now
Swelling closing the eye, or swelling under the jaw or in the floor of the mouthEmergency care now
Any difficulty swallowing, opening the mouth, or breathingEmergency services. This is an airway concern
Fever alongside dental pain or swellingSame-day urgent care
A tooth knocked out or displaced by trauma, or a jaw injurySame day — the window for replanting a knocked-out adult tooth is short
Bleeding after an extraction that will not stop with pressureContact the treating dentist or urgent care

The rule of thumb clinicians use is that pain is a dental appointment and swelling that is spreading is a medical emergency. Painkillers making the pain tolerable does not make the infection smaller.

Brushing: coverage, not force

Twice a day for two minutes is the conventional target, and the two minutes matter because the common failure is speed rather than effort. Bristles are angled toward the gum line and moved in short strokes, and the pressure should be light. Scrubbing hard and sideways with a firm brush is actively harmful over years: it wears grooves at the neck of the tooth and contributes to gum recession, which is one of the ordinary causes of sensitivity. A soft brush is sufficient for plaque, which is soft. Replace the brush when the bristles splay, commonly every few months. Of the two daily sessions, the one before bed is the one to protect, because saliva flow drops overnight.

Habits that survive are the ones with a fixed slot rather than an intention. If yours does not stick, the habit tracker maker is a plain way to see how many days actually happened, which is usually more sobering and more useful than trying harder.

The surfaces a brush cannot reach

A toothbrush cleans the outer, inner and biting surfaces. It does not clean the two faces where adjacent teeth touch, and those contact areas are where decay and gum inflammation most often start. Floss or interdental brushes are how those surfaces get cleaned, once a day.

Order is argued about more than it deserves. Cleaning between the teeth before brushing has a sensible rationale — debris is displaced first, and fluoride reaches the gaps afterwards — but the difference between orders is small next to the difference between doing it daily and not. Where the gaps are wider, or the gums have receded, interdental brushes usually clean more effectively than floss, and the size is worth having fitted at the practice rather than guessed. Light bleeding in the first days of a new flossing habit is common. Bleeding that continues past that is inflammation, and it is a reason to be examined.

Fluoride, and what it is doing

Fluoride is the best-evidenced ingredient in preventive dentistry, which is why it is in essentially every mainstream toothpaste. It works at the surface of the tooth, so the amount of contact time matters: after brushing, spitting rather than rinsing the mouth out thoroughly leaves more of it in place, which is now standard advice in several national guidelines.

Children are the case where amount is deliberately controlled, because young children swallow toothpaste. The usual guidance is a smear for the very young and a pea-sized amount for older preschool children, with brushing supervised until they can manage it properly. Higher-concentration products exist and are prescribed rather than chosen. This page does not name a concentration for your child or recommend a product — that is a question for your dentist, who will also weigh whether preventive treatments applied at the practice are appropriate for that child's risk.

What bleeding and sensitivity are telling a dentist

These are the two things people most often try to manage at home, and both are signals worth reading correctly. The table below is not a way to work out what you have; it is what a dentist is separating out and why the separation changes the treatment.

What you noticeWhat is being distinguishedWhy it matters
Gums bleed when brushingInflammation confined to the gum tissue versus disease that has begun to affect the supporting boneThe first is generally reversible with cleaning and professional care; the second involves loss that does not come back, so the timing of assessment matters
Sharp pain with coldExposed root surface or wear at the neck of the tooth versus decay reaching the inner layer versus a crackEach has a different treatment, and one of them gets worse quickly. Guessing between them delays the one that needed attention
Lingering pain, or pain that starts unpromptedWhether the nerve inside the tooth is involvedThis changes the scale of treatment substantially and is not something to wait out
Pain on biting, or a gum swelling near one toothA crack, a failing restoration, or infection at the root tipLocalised swelling is the stage before the spreading swelling in the emergency section above

One piece of advice contradicts intuition and is worth repeating: bleeding gums are not a reason to brush that area less. The bleeding comes from inflamed tissue, the inflammation is driven by what is not being removed, and avoiding the area makes it worse. Clean it more carefully, with a soft brush, and have it looked at.

Why decay is cheaper to treat early

Decay progresses through the tooth in stages, and each stage that passes makes the treatment larger, longer and more expensive. The point of the table below is not to help you stage your own tooth — you cannot see most of this, which is the entire problem — but to show why check-ups happen when nothing hurts.

StageWhat is happeningScale of treatment
Enamel onlySurface demineralisation. Typically no symptoms at allOften monitoring and preventive measures; a small restoration at most
Into the dentineSensitivity to cold or sweet may appearA filling, larger if the area has spread
Reaching the pulpSpontaneous or lingering pain; the nerve is involvedRoot canal treatment and usually a crown
Tooth structure lostThe crown of the tooth breaks downExtraction, then a decision about replacement

The first row is silent. That is the whole argument for periodic examination: the cheap stage does not announce itself, and by the time something hurts the decision has usually already moved a row or two down the table. Your dentist sets the interval based on your risk rather than a universal number.

Two things this page will not do

It will not tell you what your symptom means, and it will not suggest what to take for dental pain. Both belong to the dentist or doctor who can look at the tooth. What it can leave you with is a shorter list to act on: keep the twice-daily routine and the daily clean between the teeth, keep the appointment you do not think you need, treat spreading swelling as an emergency rather than a scheduling problem, and mention grinding or jaw clenching if you notice it — persistent jaw and temple soreness on waking is worth raising, and if it overlaps with headaches, the headaches guide covers the record that makes that appointment more productive, while the sleep hygiene guide covers the other half of a night you may not be sleeping through.

Questions people ask

When is a dental problem an emergency rather than an appointment?

When there is facial swelling that is spreading or came up quickly, swelling that closes the eye or sits under the jaw or in the floor of the mouth, any difficulty swallowing, opening the mouth or breathing, or fever alongside dental pain. Those go to emergency care rather than onto a waiting list. A knocked-out adult tooth is also same-day, because the window for replanting it is short.

Should I floss before or after brushing?

There is a reasonable argument for cleaning between the teeth first, since debris is displaced before fluoride toothpaste reaches those gaps, but the difference between the two orders is small compared with the difference between doing it every day and not. Where gaps are wider or gums have receded, interdental brushes usually clean better than floss, and the practice can fit the right size.

My gums bleed when I brush. Should I be gentler on that spot?

Not by avoiding it. Bleeding usually reflects inflamed gum tissue, and the inflammation is driven by what is not being removed from that area, so cleaning it less makes it worse. Use a soft brush, clean the area carefully including between the teeth, and have it examined — persistent bleeding is the point at which a dentist distinguishes between inflammation limited to the gums and disease affecting the supporting bone.

Why do my teeth hurt with cold?

Several different things produce that, including exposed root surface after gum recession, wear at the neck of the tooth from heavy sideways brushing, decay that has reached the inner layer, and a cracked tooth. They are treated differently and one of them progresses quickly, which is why a dentist separates them rather than a page doing it. Sharp pain with cold that lingers after the cold is removed is worth an appointment rather than a wait.

Does the amount of toothpaste matter for young children?

Yes, because young children swallow it. Standard guidance uses a smear for the very young and a pea-sized amount for older preschool children, with brushing supervised until a child can manage it properly. Specific concentrations, and any question of preventive treatments applied at the practice, are set by your dentist based on that child, so ask there rather than following a figure from a website.

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