How do I brush a dog's teeth?

Building up to it over a fortnight rather than starting with a brush, which surfaces actually matter, and the signs that mean a vet rather than more brushing.

Difficulty: beginner
Time: 10 min
Read: 5 min
Safety: warning

Short answer

Build up over two or three weeks — touching the muzzle, then lifting the lip, then dog toothpaste on a finger, then a brush — and only then start brushing properly. Brush the outer surfaces only, for about thirty seconds a side, daily. Use dog toothpaste, never human.

Dental disease is one of the most common conditions vets see, and it is painful long before an owner notices, because dogs keep eating through it. Brushing is the only home measure that meaningfully reduces plaque before it hardens into tartar, and it works only if it is close to daily — a weekly brush achieves very little. The reason most people give up is that they start with a toothbrush in a dog's mouth on day one, which almost no dog accepts.

Safety

Only ever use toothpaste made for dogs. Human toothpaste contains fluoride, which dogs should not swallow, and some brands contain xylitol, which is seriously toxic to dogs. Stop and see a vet if the gums bleed readily, if the breath is genuinely foul, if a tooth is broken or discoloured, if there is a swelling on the face or under an eye, or if the dog flinches or snaps when a particular tooth is touched — all of these mean pain, and brushing a painful mouth makes both the pain and the dog's tolerance worse. Never try to scrape tartar off a tooth yourself.

What you'll need

Dog toothpaste
A dog toothbrush or a finger brush
A soft child's toothbrush as an alternative (optional)

Step by step

Days one to three: touch the muzzle and pay for it.Sit beside the dog, briefly hold the muzzle, give a treat, let go. Ten seconds, several times a day. Nothing goes in the mouth yet.
Days four to six: lift the lip.Lift the side of the lip to expose the outer surfaces of the back teeth for a second, then treat. Both sides. Still nothing in the mouth.
Days seven to nine: introduce the toothpaste as food.Dog toothpaste is flavoured to be palatable. Let the dog lick a small amount off your finger so it becomes a treat rather than a procedure.
Days ten to twelve: rub the paste on with a finger.Lift the lip and run a paste-covered finger along the outer surfaces of a few teeth. A few seconds each side, then stop and reward.
Days thirteen onwards: introduce the brush.Paste on the brush, lift the lip, and do a few teeth at the front on one side. Add teeth each session rather than trying to do the whole mouth immediately.
Brush the outer surfaces only.The outside faces of the teeth, especially the large upper cheek teeth at the back, are where tartar accumulates and where you can reach safely. The tongue does a reasonable job on the inner surfaces, and trying to get in there is what gets people bitten.
Angle the brush towards the gum line at about forty-five degrees.Small circular movements along the gum line, which is where plaque does its damage. About thirty seconds a side is a realistic and useful session.
Do it daily, at the same point in the routine.Plaque begins to harden into tartar within a couple of days, so daily is the target and every other day is the useful minimum. Attaching it to an existing habit — after the evening walk, before the last meal — is what makes it stick.
Stop immediately if anything hurts.Flinching, pulling away sharply from one spot, blood that appears readily, or a dog that suddenly objects after weeks of accepting it. Book a vet. A painful mouth is not something to work through.
Have the mouth checked at the annual vet appointment.Brushing slows plaque but does not remove tartar that has already hardened, and only a vet can do that, under anaesthetic. Anyone offering anaesthetic-free scaling is polishing the visible surface and leaving the disease under the gum line.

Tips

If the dog will only tolerate a finger brush and never a real toothbrush, keep using the finger brush. Something done daily beats something better done never.
Dental chews and dental diets help a little and are not a substitute for brushing. They are worth using, but count them in the day's food.
Small breeds and flat-faced breeds get dental disease earlier and more severely because the teeth are crowded. If you have one, start brushing as a puppy rather than when the problem appears.

Common mistakes

Using human toothpaste — It contains fluoride that should not be swallowed, and some brands contain xylitol, which is seriously toxic to dogs. Dog toothpaste is designed to be swallowed.
Starting with a toothbrush on the first day — Almost no dog accepts it, the dog learns that this is unpleasant, and the owner concludes it is impossible. The fortnight of build-up is what makes it work.
Brushing once a week — Plaque hardens into tartar within a couple of days. Weekly brushing does not keep up with it, which is why the frequency matters more than the thoroughness.
Trying to chip tartar off with a fingernail or a scaler — It damages the enamel, leaves a rougher surface for plaque to stick to, and does nothing about disease below the gum line. That is a veterinary procedure.

If it doesn't work

Dog clamps its mouth shut

Cause: Moved through the stages too fast — Fix: Go back two stages, work at lifting the lip only with high-value food for a week, and rebuild from there.

Gums bleed a little at first

Cause: Existing gingivitis — Fix: A small amount at the very start of a brushing routine is common and settles within a week or two. Bleeding that is readily provoked, or continues past that, needs a vet.

Breath is still bad despite daily brushing

Cause: Established tartar or disease under the gum line — Fix: Book a vet dental assessment. Brushing prevents new plaque but cannot remove what has already hardened.

Dog suddenly refuses after weeks of accepting it

Cause: Pain — a fractured tooth or an abscess — Fix: Stop brushing and see a vet. A sudden change in tolerance is a symptom, not a training regression.

Questions people ask

How often should I brush my dog's teeth?

Daily is the target, because plaque starts hardening within a couple of days. Every other day is worthwhile; once a week achieves very little.

Do dental chews work instead of brushing?

They help modestly and they are not a replacement. Brushing is the only home measure that removes plaque from the gum line, which is where the damage happens.

Do I need to brush the inside of the teeth?

No. The outer surfaces are where tartar builds and where you can safely reach, and the tongue keeps the inner surfaces reasonably clear. Trying to reach the inside is where people get bitten.