Common dental diseases in dogs and the signs to watch

Last updated October 17, 2026

Gum disease is by far the most common dental disease in dogs. Plaque builds up where the teeth meet the gums, hardens into tartar, and inflames the gums and then the bone that holds each tooth. Broken teeth come next. The rest are less common, and nearly all of them are a job for your vet.

Home care keeps plaque down on teeth that are already clean. It can't repair a broken tooth or rebuild bone that gum disease has taken. A swollen face, a freshly broken tooth or a dog that stops eating needs a vet the same day.

Dental problems at a glance

Condition	What you might notice	Can home care help?
Plaque and early gingivitis	Bad breath, a red line along the gums	Yes, daily brushing
Tartar	Hard yellow or brown crust at the gumline	Only to slow new buildup after a vet cleaning
Periodontitis	Receding gums, loose teeth, bad breath	Slows it, can't reverse it
Broken tooth	A chipped tip, a pink or black dot in the break	No
Tooth root abscess	Swelling under the eye, chewing on one side	No
Pink, purple or gray tooth	One tooth the wrong color	No
Tooth resorption	Often nothing at all	No
Retained baby tooth	Two teeth in one spot in a puppy	No
Stomatitis	Raw ulcers where the lips touch the teeth	Plaque control is part of the vet's plan
Oronasal fistula	Sneezing, a runny nose that won't clear	No
Lump on the gum	A growth, bleeding, a tooth shifting	No

Gum disease is the one most dogs get

Plaque is a soft film of bacteria that forms on teeth every day, and minerals in saliva harden it into tartar. The gums react first. That stage is gingivitis, and it's the only one that fully goes away once the teeth are cleaned and kept clean.

The bacteria in plaque aren't one germ. Hundreds of kinds live in a dog's mouth, and as plaque sits at and under the gum line the mix shifts toward ones that thrive without oxygen. Our guide to the bacteria behind gum disease covers the best-studied of them, Porphyromonas gulae. It's so common, carried by 82% of 665 small dogs in one Japanese study, that finding it doesn't mean a dog has gum disease.

When the inflammation reaches the ligament and bone around the tooth, it's periodontitis. The American Veterinary Dental College (AVDC) stages each tooth from PD1, gingivitis alone, to PD4, where more than half of the tooth's support has gone. Lost bone doesn't grow back, and the gums can look fairly normal while it goes.

Our guide to the stages of periodontal disease sets out what you might see at each stage, what only the probe and X-rays show, and what home care can still do. In one study of 89 dogs, a look in the mouth of an awake dog matched the real stage in about 4 dogs in 10, and among the stages with bone loss it did worst at stage 2, where that loss begins. From stage 2 on, home care can keep a treated tooth stable but can't change its stage.

When Stepaniuk and colleagues (2026) examined 369 dogs under anesthesia, 98.6% had at least gingivitis and 59.6% already had periodontitis. Small dogs get it sooner. In UK vet records for 22,333 dogs, the odds of a diagnosis fell steadily as body weight went up (O'Neill and colleagues, 2021).

In a study of 52 miniature schnauzers, about one in five teeth with only the mildest redness went on to periodontitis within 60 weeks (Marshall and colleagues, 2014). Our gingivitis and periodontitis guide shows what each stage looks like and how a vet treats both.

Plaque and bad breath come first

Fresh plaque is soft and a toothbrush gets it off, but it can be hard tartar within 2 to 12 days (Lowe and Anthony, 2020). A piece of gauze tells the two apart, and our page on getting plaque off dog teeth shows how. In a 2025 trial on teeth that hadn't been cleaned first, no brushing, chew or additive routine got them clean (Gawor and colleagues, 2025).

Bad breath is one of the earliest signs of gum disease. The smell is mostly sulfur gases from plaque bacteria (Culham and Rawlings, 1998). Sweet breath or an ammonia smell points elsewhere and needs a vet soon. Why your dog's breath smells bad sorts each smell by how urgent it is.

Broken and worn teeth

In the same 2026 study, 50.9% of the dogs had at least one fractured tooth. The usual cause is chewing something harder than a tooth, such as cooked or dense leg bones, antlers, hooves, hard nylon toys or ice.

The big upper cheek tooth, the carnassial, takes more force than the canines when a dog chews. In a lab test these teeth broke at about 130 kg (290 lb) of force, within an average dog's bite (Soltero-Rivera and colleagues, 2018).

Our guide to the carnassial tooth explains which two teeth these are on each side, the upper fourth premolar on top and the lower first molar below, and why the upper one cracks most often. Because its three roots reach up close to the eye, an infected carnassial usually surfaces as a firm swelling below the eye, and saving it means a root canal or a surgical extraction rather than a quick pull.

Our guide to dog mouth anatomy explains what each of the 42 adult teeth does, the carnassials included.

A pink or red dot in the break, or a dark hole, means the pulp is open to the mouth. That hurts even if your dog keeps eating, and the tooth needs a root canal or extraction. In Clarke's 2001 study of fractured canine teeth given vital pulp therapy, 88.2% were still alive three years on when treated within 48 hours, against 23.5% when treatment took up to three weeks.

Dogs tend to hide mouth pain like this, and many keep eating. Our guide to the signs of tooth pain in a dog lists the quieter clues, such as dropped food, chewing on one side, leaving hard biscuits or pulling away when you touch the face, and how soon each one needs the vet. In a 2026 study of small dogs enrolled for severe dental disease, only 19 of 52 owners thought their dog was in pain before treatment.

Tooth root infections and abscesses

A tooth root abscess is a pocket of pus at the tip of a root, usually in a tooth whose pulp died after a break or where deep gum disease has crept down the root. On the upper carnassial it often shows as a swelling just below the eye. Antibiotics can calm it, but the infection comes back until the tooth is root-treated or taken out. Our dog tooth abscess page covers how your vet confirms one and how fast to book.

Discolored teeth

A tooth that turns pink, purple or gray all through usually has a bruised or dead pulp. In Hale's 2001 study, 59 of 64 such teeth (92.2%) had partial or complete pulp death when opened. Brown or yellow crust at the gumline is usually tartar on the outside of a healthy tooth. Discolored teeth in dogs goes through each color and what your vet does about it.

Problems you can't see from the outside

In tooth resorption the tooth is slowly broken down from the root, and it usually only shows on X-rays. Peralta and colleagues (2010) found it in 53.6% of 224 dogs X-rayed at a university dentistry service, dogs already in for dental work, so the share in all dogs is likely lower.

True cavities are rare by comparison. In Hale's 1998 records of 435 dogs at a dental referral practice, 23 had one or more, mostly on the big back teeth, and a dog's less acidic saliva is one likely reason. Our guide to cavities in dogs shows how to tell a cavity from tartar or a stain, and how a vet fills one.

Gum disease is also easy to miss. When Queck and colleagues (2018) checked 114 dogs awake and then under anesthesia with X-rays, the awake look underestimated how much disease there was and how bad. The WSAVA's global dental guidelines make an exam with X-rays under anesthesia the standard of care.

In a review left on seaweed.co on 27 May 2024, one owner wrote, "My oldest dog is 15, still has all his teeth, and they're strong - but he had a lot of tartar and his breath was awful!" Teeth like these can be sound, or the bone around their roots can be going, and only that exam with X-rays shows which. Tartar with bad breath is worth raising at the next vet check at any age, and sooner if the gums are red.

A breath freshener can hide that warning sign. Mints and scented sprays only lay a pleasant smell over the odor for a while. Daily dental chews, brushing and some gels lowered the smell itself in dog trials, though that took from one week to two months. Our guide to whether dog breath fresheners work compares each type, and none of them reliably removes tartar that has already hardened.

A fishy smell is different, because it may not start in the mouth at all. It usually comes from the anal sacs under the tail, which a dog that licks its rear end carries to its mouth, from fish in the food, treats or a fish oil supplement, or from plaque bacteria on the teeth. Our guide to fishy breath in dogs sets out a sniff test that checks each source in turn, starting with a gauze pad wiped along the back teeth before breakfast, when a mouth smell is easiest to catch.

Puppy teeth and bite problems

Sometimes a baby tooth, most often a canine, stays put as the adult one comes in. Two teeth in one space push the adult tooth out of line and trap food. The Merck Veterinary Manual advises extracting the baby tooth once its replacement has started to come through. In US vet records covering almost 3 million dogs, Wallis and colleagues (2024) found retained baby teeth in 7% of pure-bred dogs and 15% in breeds under 6.5 kg.

A bad bite, which vets call malocclusion, can push teeth into the gums or the roof of the mouth, and is best assessed while the puppy is young.

Our puppy teething timeline follows the change from the first baby teeth at 3 to 5 weeks to all 42 adult teeth by about 7 months. Most puppies swallow their baby teeth, so the useful job for an owner is a look at about six months for a baby tooth still sitting beside its adult replacement. Very small breeds run about a month late and are the most likely to keep one.

While the adult teeth push through, a puppy chews more to ease sore gums, and the safe outlet is something cold and soft. Our teething remedies for puppies cover the chilled toys, frozen washcloths and held carrots that help, the thumbnail test for whether a chew is soft enough, and the items to keep away, from ice cubes and hard bones to human teething gels and anything with xylitol.

Stomatitis, oronasal fistulas and lumps

Chronic ulcerative stomatitis is a painful immune over-reaction to plaque, with raw ulcers where the lining of the lips and cheeks rests against the teeth. In a 2025 study of 42 dogs with stomatitis, half of them confirmed as the chronic ulcerative type, 81% had their ulcers clear completely, most without having every tooth removed (Ford and colleagues, 2025). The steps vets usually take are in stomatitis in dogs.

An oronasal fistula is a hole between the mouth and the nose. The WSAVA guidelines call it the most common severe local result of gum disease, usually beside an upper canine, and mostly in older small breeds and Dachshunds. The signs are a runny nose and sneezing that don't clear. It needs surgery, and in a study of 80 dogs, 89% healed with no signs left (Lorida and colleagues, 2025). Repair and recovery are covered in oronasal fistulas in dogs.

Any lump on the gums needs a vet, even a small one. Some growths are benign and some are cancer, and a biopsy tells them apart.

Gum color can point to a problem outside the mouth too. Our guide to what your dog's gum color means treats pale, white, blue, gray or bright red gums as a reason to go to a vet now and yellow gums as a same-day visit, and shows how to do the two-second refill test. It also covers dark spots, since a vet can't tell a harmless growth from melanoma by eye.

What home care can and can't do

Daily brushing with a dog toothpaste is the most effective home care, and it comes first in the WSAVA guidelines. The Veterinary Oral Health Council (VOHC) lists chews, diets and other products that met its standard for slowing plaque or tartar. If your dog won't accept a brush, our guide to cleaning dog teeth without brushing compares the options.

Hard tartar and anything under the gumline need a cleaning under anesthesia. The AVDC opposes scaling an awake dog, because the part below the gums can't be cleaned or checked that way. If cost is a worry, ask your vet for an itemized estimate.

When to see a vet

• The same day for a swollen face, a freshly broken tooth with a pink or red dot, bleeding from the mouth that won't stop, or a dog that has stopped eating.
• Within a few days for a tooth that has turned pink, purple or gray, sores inside the lips, a runny nose that won't clear, or chewing on one side.
• Within a week or two for a lump on the gums, a loose tooth, or bad breath with red gums.
• At the next check for tartar on otherwise comfortable teeth, or a puppy whose bite looks off.

Questions owners ask

How long can a dog live with dental disease?

There's no fixed answer. Many dogs live with gum disease for years, often in pain they hide well. Treatment makes those years more comfortable, so don't wait until your dog stops eating.

Can dental disease in dogs be treated at home?

Only the earliest stage. Gingivitis settles once plaque is controlled. Tartar, periodontitis, broken teeth and infections need a vet.

Can dental disease affect the rest of my dog's body?

Possibly, though it isn't proven. In records for nearly 60,000 dogs with gum disease and as many without, worse gum disease went with more heart problems later, such as endocarditis (Glickman and colleagues, 2009). A post-mortem study of 44 small Poodles linked it with changes in the heart valves, liver and kidneys (Pavlica and colleagues, 2008). The pain is better established, and the WSAVA guidelines count untreated dental disease as a welfare problem.

References

• Clarke DE. Vital pulp therapy for complicated crown fracture of permanent canine teeth in dogs, a three-year retrospective study. J Vet Dent. 2001;18(3), 117-121.
• Culham N, Rawlings JM. Oral malodor and its relevance to periodontal disease in the dog. J Vet Dent. 1998;15(4), 165-168.
• Ford J, Bell C, Donovan TA, Martel D. Surgical outcomes in canine lymphoplasmacytic stomatitis, a retrospective study of 42 dogs (2012-2022). Front Vet Sci. 2025;12, 1681133.
• Gawor J, Jank M, Harvey CE, Nicolas CS. Effectiveness of dental homecare protocols in unscaled dogs. J Vet Dent. 2025;42(3), 176-181.
• Glickman LT, Glickman NW, Moore GE, Goldstein GS, Lewis HB. Evaluation of the risk of endocarditis and other cardiovascular events on the basis of the severity of periodontal disease in dogs. J Am Vet Med Assoc. 2009;234(4), 486-494.
• Hale FA. Localized intrinsic staining of teeth due to pulpitis and pulp necrosis in dogs. J Vet Dent. 2001;18(1), 14-20.
• Kyllar M, Witter K. Prevalence of dental disorders in pet dogs. Vet Med (Praha). 2005;50(11), 496-505.
• Lorida O, Nikita GE, Chortara I, Papadimitriou S. Acquired oronasal fistulas due to periodontitis in dogs, a retrospective study of 80 cases (2019-2024). Hellenic Journal of Companion Animal Medicine. 2025;14(2).
• Lowe C, Anthony J. Pilot study of the effectiveness of a xylitol-based drinking water additive to reduce plaque and calculus accumulation in dogs. Can Vet J. 2020;61(1), 63-68.
• Marshall MD, Wallis CV, Milella L, Colyer A, Tweedie AD, Harris S. A longitudinal assessment of periodontal disease in 52 miniature schnauzers. BMC Vet Res. 2014;10, 166.
• Niemiec B, Gawor J, Nemec A, et al. World Small Animal Veterinary Association Global Dental Guidelines. J Small Anim Pract. 2020;61(7), E36-E161. Updated edition, J Small Anim Pract. 2026;67(10), 859-987.
• O'Neill DG, Mitchell CE, Humphrey J, Church DB, Brodbelt DC, Pegram C. Epidemiology of periodontal disease in dogs in the UK primary-care veterinary setting. J Small Anim Pract. 2021;62(12), 1051-1061.
• Pavlica Z, Petelin M, Juntes P, et al. Periodontal disease burden and pathological changes in organs of dogs. J Vet Dent. 2008;25(2), 97-105.
• Peralta S, Verstraete FJM, Kass PH. Radiographic evaluation of the types of tooth resorption in dogs. Am J Vet Res. 2010;71(7), 784-793.
• Queck KE, Chapman A, Herzog LJ, et al. Oral-fluid thiol-detection test identifies underlying active periodontal disease not detected by the visual awake examination. J Am Anim Hosp Assoc. 2018;54(3), 132-137.
• Soltero-Rivera M, Elliott MI, Hast MW, et al. Fracture limits of maxillary fourth premolar teeth in domestic dogs under applied forces. Front Vet Sci. 2018;5, 339.
• Stepaniuk KS, Gingerich W, Ziche AM. Oral examination in a random anesthetized canine population for the prevalence of periodontal disease and fractured teeth. J Vet Dent. 2026, online ahead of print.
• Wallis C, Ivanova A, Holcombe LJ. Persistent deciduous teeth, association of prevalence with breed, breed size and body weight in pure-bred client-owned dogs in the United States. Res Vet Sci. 2024;169, 105161.
• American Veterinary Dental College. Nomenclature (periodontal disease stages) and position statement on companion animal dental scaling without anesthesia.
• Merck Veterinary Manual. Developmental abnormalities of the mouth and dentition in small animals (Mulherin BL, 2024); Oral inflammatory and ulcerative disease in small animals (Mulherin BL, 2024); Disorders of the mouth in dogs (Reiter AM, 2026).
• Veterinary Oral Health Council, vohc.org.