An adult dog carries 42 permanent teeth: 12 incisors, 4 canines, 16 premolars, and 10 molars. They split 20 on top and 22 on the bottom, because the lower jaw holds an extra pair of molars on each side. Incisors nibble and groom, canines grip and hold, premolars shear meat off bone like scissors, and molars grind. Puppies run a smaller set, 28 deciduous teeth, with no baby molars at all.
The count, laid out by type
The dental formula, translated
Veterinary charts write one side of the mouth and double it. Upper: three incisors, one canine, four premolars, two molars. Lower: three incisors, one canine, four premolars, three molars.
Add both sides and you get 42. That third lower molar is the one people forget, tucked so far back that many owners have never laid eyes on it.
What the incisors are for
Twelve small teeth in a tight row, sized in ascending order from the middle outward. Dogs use them to strip meat from bone, nibble burrs out of a paw, and pull at grass.
They also do the social work: mutual grooming between dogs is mostly an incisor activity. Their roots are short, which is why they are often the first teeth to loosen when the supporting structures around them change.
Canines: four teeth, enormous roots
The visible crown of a canine is roughly a third of the tooth. The root runs deep along the jaw, and in the upper jaw it sits right beside the nasal passage.
That anatomy matters. Damage or long-standing infection around an upper canine can involve structures next door, which is why any wobble in one of the four is a call to your veterinary clinic rather than a wait-and-see.
Premolars, the shearing set
Sixteen premolars form the scissor action along the sides. They interlock as the jaw closes, sliding past each other rather than meeting flat.
The upper fourth premolar is the largest tooth on top, and it is the single most commonly fractured tooth in dogs who chew antlers, hooves, cooked bones, and rocks. A vertical crack in the side of that tooth is called a slab fracture, and it is easy to miss because the piece often stays in place.
Molars, and the grinding surfaces
Ten molars finish the arcade at the back. Their crowns are flatter and lumpier than everything in front, built for compression instead of cutting.
They also sit where a toothbrush rarely reaches and where an owner's eye almost never travels. Buildup back there is often well established by the time it becomes visible from the front.
Puppies: 28 teeth, then a rapid handover
Deciduous teeth erupt from roughly three to six weeks of age, and there are 28 of them. Puppies get no molars and no first premolars in the baby set.
The exchange runs from about three months to seven months. Incisors go first, then canines and premolars, with the last molars settling in around six or seven months. A baby tooth still standing beside its adult replacement at eight months should be checked; retained deciduous teeth crowd the new tooth and trap debris where nothing can clean it.
Why 42 teeth in a 9-pound dog is a design problem
The number is fixed regardless of body size. A Chihuahua and a Rottweiler both carry 42, packed into jaws that differ by a factor of ten in length.
Crowding, rotation, and overlapping roots follow, and so does trapped plaque at every contact point. Small and toy breeds therefore need earlier and more frequent attention than their size suggests. Breed-specific feeding and care notes on the AKC's nutrition pages are a reasonable starting point for how those differences play out day to day.
Which teeth get dirty first
Two locations, reliably: the outer face of the upper fourth premolar and the inside surface behind the lower canines and incisors. Salivary ducts empty near both.
If you only ever inspect two spots on your dog, inspect those. They are the early-warning stations for the whole mouth.
Keeping 42 surfaces clean with a two-minute routine
Brushing hits the outer faces, which is where most visible buildup lives. What owners under-clean is the back third, and the fix there is chewing time rather than more brushing effort.
A chew that requires real work keeps abrasive contact against the premolars and molars for minutes at a stretch. Ark Naturals Brushless Toothpaste is built around that idea, with a ridged outer texture for friction and a center that serves as a source of toothpaste-style cleaning ingredients; Protection+ adds an Asta-Shield coating carrying astaxanthin. Sizes are matched to body weight across the dog range, which matters more than it sounds, since a chew sized for a 70-pound dog gets swallowed whole by a 15-pound one. For how dental products are evaluated, the Veterinary Oral Health Council's list is worth a look.
Common questions about dog teeth counts
How many teeth should my adult dog have?
Forty-two, though plenty of healthy adult dogs have 40 or 41 because a small tooth never developed or was extracted years ago. Your vet records the exact count on a dental chart at each cleaning.
Do dogs lose adult teeth naturally with age?
No. Loss of a permanent tooth reflects a problem with the tooth or the tissue holding it, not normal aging, so any adult tooth that goes missing should be mentioned at your next appointment.
My puppy is 5 months old and has two rows of front teeth. Is that normal?
It is common during the handover and usually sorts itself out within weeks. If a baby tooth is still there once the adult tooth is fully up, ask your vet whether it needs to come out.
Which of my dog's teeth is most likely to break?
The big upper fourth premolar, the one right at the top of the cheek. Hard antlers, cooked bones, and ice cubes are the usual culprits.