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Dog breath is not a personality trait. It is usually bacteria under the gumline, and it means something has already started. Most dogs and cats show some gum change by about three years old, pets keep eating through real pain, and the part that matters cannot be seen from outside the mouth.
The sign everybody notices and nobody acts on
Almost every owner has smelled it. You lean down, your dog breathes at you, and you pull back. Then you file it under dog breath and carry on, because that is what everyone says it is.
It is worth stopping there, because that smell has a cause. It is usually produced by bacteria living in and under the gum margin, and a healthy mouth rarely smells. Occasionally the source is not the mouth at all but the kidneys, a diabetic problem, or a mass or foreign body, which is another reason to have it looked at rather than lived with. A puppy does not smell like that. A cat with a clean mouth does not either. When the smell appears, something has changed.
This is one of the most commonly dismissed signs in companion animal health, and the reason is simple: it arrives slowly. Nothing happens on a particular Tuesday. The smell creeps up over a year or two, the household adjusts to it, and by the time anyone mentions it at an appointment, there is usually a fair amount to do.
What is actually happening in there
Plaque is a soft film of bacteria, and it starts forming on a clean tooth within about a day. Left alone, minerals in the saliva harden it into tartar, the brown-yellow crust you can see along the gumline. That takes only a few days.
Two things follow from that timeline. First, brushing works because it disrupts plaque before it hardens, which is why frequency matters far more than technique. Second, once tartar has formed, nothing you do at home removes it. No chew, no additive, no brushing. It is attached to the tooth and has to be taken off.
But the visible crust is not the problem. It is the marker. The actual damage happens underneath, where plaque bacteria sit in the space between tooth and gum, the gum pulls away, and the structures holding the tooth in place are gradually lost. That is why a mouth can look only mildly dirty and still have teeth that need to come out, and why two pets with identical-looking tartar can need completely different work.
Why “he is still eating” is not reassurance
This is the sentence we hear most, and it is the one that costs pets the most time.
Animals do not stop eating because their mouth hurts. Eating is not optional for them, and the instinct to hide weakness runs deep in both dogs and cats. A pet with a painful mouth adapts instead. They swallow kibble whole rather than chewing it. They chew on one side. They carry a toy less, or stop playing tug, or turn their head away when you touch the side of their face. A cat stops grooming as thoroughly and starts to look slightly unkempt.
What owners tell us afterwards is remarkably consistent. Weeks after a dental procedure, people describe a pet who is brighter, more playful and more affectionate, and say they had not realized anything was wrong. The pain was never absent. It was just quiet.
What to look for at home
Once a week, lift the lip on both sides and look at the back teeth, where problems start. You are checking for:
- The smell. Any noticeable odour, and especially one that has grown stronger.
- A red line along the gum where it meets the tooth. Healthy gums are an even colour with a clean margin.
- Brown or yellow crust, particularly on the large teeth at the back and on the upper canines.
- Gums that bleed when touched, or pink saliva on a chew toy or in the water bowl.
- A broken or discoloured tooth. A grey or purple tooth is usually a dead tooth and needs assessing even though it looks settled.
- Drooling, dropping food, or chewing on one side.
- Pawing at the face, or turning away when you touch one side of the muzzle.
- A firm swelling below one eye. That is often an abscess at a tooth root and should be seen promptly rather than watched.
Cats deserve their own line. Cats develop painful lesions at the gumline where the tooth structure itself breaks down, and these are genuinely common in middle-aged and older cats. A cat who has started eating on one side, dropping food, pulling away from the bowl mid-meal, or chattering their jaw is worth a look even if their teeth appear clean.
What a dental visit actually involves
We start with an examination and a conversation about what you have noticed at home. From there a proper dental procedure happens under anaesthesia, and that is not a convenience. An awake animal will not allow the gumline to be probed, cannot have the tooth surfaces cleaned below the gum, and cannot hold still for the imaging that shows what is going on underneath.
Dental X-rays are the part most owners have not heard about and the part that changes decisions most often. A large share of what matters sits below the gum: root damage, bone loss, resorptive lesions in cats, abscesses with nothing visible above the surface. Ask us whether dental radiographs will form part of your pet’s procedure, since that is worth settling in advance. Our in-house diagnostics page sets out the laboratory and imaging work we run alongside it.
Then the teeth are cleaned above and below the gumline, charted tooth by tooth, polished, and anything beyond saving is dealt with. Our dental services page explains the process, what to expect on the day, and where dental radiographs fit in.
A word on anaesthesia-free dental cleaning. It is offered in various places and it is worth understanding what it is. Scraping visible tartar off the crown of a tooth in a conscious animal makes the mouth look better and leaves the part that causes the damage, below the gumline, completely untouched. It also cannot include imaging. An owner can come away believing the problem is handled when nothing meaningful has changed, and the pet has been restrained for it. If anaesthesia worries you, and it reasonably might, the productive conversation is about how we reduce that risk for your individual animal, not about avoiding the procedure that actually works.
Keeping a clean mouth clean
Brushing is the single most effective thing you can do, and daily beats weekly by a wide margin because of how fast plaque reforms. Use a paste made for pets, never one made for people, because human toothpaste contains fluoride and sometimes xylitol and your pet will swallow it. Start by letting your pet lick it off your finger for a few days, then a finger along the outer surfaces, then a brush. The outside surfaces are where it matters; you do not need to get behind the teeth.
If brushing is genuinely not possible in your household, and for some pets it is not, there are chews, diets, water additives and wipes that help. Choose ones carrying the Veterinary Oral Health Council seal, since that means trial data on plaque or tartar control has been reviewed rather than simply claimed in marketing, and ask us which suits your pet. Avoid very hard chews, real bones, antlers and hooves, which fracture teeth. A good rule is that if you cannot make a dent in it with a thumbnail, it is hard enough to break a tooth.
Mouths get checked at every wellness services visit, which is usually where this gets picked up before an owner has noticed anything at all. While we are on the subject of things owners put off, our guide to broken nails and easier nail trims covers another routine job that hurts more than people expect when it is left.
Our hours, and what cannot wait
We are open Monday to Friday from 8:00 AM to 9:00 PM, Saturday from 8:00 AM to 6:00 PM, and Sunday from 8:00 AM to 3:00 PM. Most dental concerns are a booked appointment rather than an urgent visit, and bad breath, tartar or a gradually developing problem can comfortably wait for one.
Some things should not. A firm swelling below the eye, a fractured tooth with bleeding, a pet who has suddenly stopped eating entirely, who cannot close their mouth, or who is bleeding from the mouth and will not settle, needs same-day attention through our urgent care. Sunday evenings and overnight are the longest stretches we are closed, so if any of that happens outside our hours, go to an open emergency veterinary hospital and call ahead on your way.
Common questions
My dog’s breath has always smelled. Is that just him?
No. Breath odour is usually produced by bacteria at and below the gumline, and a healthy mouth rarely generates it. A few causes sit outside the mouth entirely, which is a further reason to check rather than assume. “Always” usually means it started slowly enough that nobody marked the date. It is worth having the mouth looked at properly rather than accepting it as his normal.
How often do pets need a dental procedure?
It varies enormously and depends on the individual more than the calendar. Small breeds, flat-faced breeds and cats generally need attention sooner and more often. In small and flat-faced dogs that is crowding, which traps more plaque; in cats it is resorptive lesions, which hide from a visual check. Some pets need one every year, others every few years. The honest answer comes from looking in the mouth rather than from a rule.
Is anaesthesia safe for an older pet?
Age on its own is not the deciding factor; health status is. We discuss pre-anaesthetic bloodwork, tailor the plan to your animal, and monitor throughout. It is also worth weighing against the alternative, because leaving an infected mouth in place has its own cost for an older pet, carried every day rather than for one morning.
Will brushing fix tartar that is already there?
No. Brushing prevents new plaque from hardening, which is genuinely valuable, but tartar is bonded to the tooth and only comes off with instruments. Start brushing anyway, because it protects everything that gets cleaned and slows how quickly you are back.
My cat will not let me near her mouth.
Many will not, and forcing it damages the relationship you need for everything else. Do what you can, use something she tolerates, and let us check the mouth at her visits. Cats are also the group where problems hide best, so a professional look matters more for her, not less.
What does a dental procedure cost?
It depends on what we find, because a clean and polish and a mouth needing several extractions are different pieces of work. We will examine first, give you an estimate before anything is booked, and talk through what is necessary now and what can reasonably wait.
Speak to the team at Columbia Square Animal Hospital
If your pet’s breath has changed, if you have spotted tartar or a red gumline, or if you simply cannot remember the last time anyone looked properly, call us and book an examination. If something sudden happens outside our hours, go to an open emergency veterinary hospital and call ahead before you leave.
Published by the team at Columbia Square Animal Hospital.
This article is educational in nature and is not a replacement for hands-on assessment of your own pet by a veterinarian.
Columbia Square Animal Hospital
#104, 78 Tenth St, New Westminster, BC V3M 3X3
Phone: (604) 521-5572
Email: receptioncsah@gmail.com
Hours: Monday to Friday 8:00 AM to 9:00 PM; Saturday 8:00 AM to 6:00 PM; Sunday 8:00 AM to 3:00 PM