Dogs belong to the canine family, and their dental system is similar in structure to that of other predatory mammals.
Long, dagger-like canines are used by domestic dogs to hold a large piece of meat, while their wild hunting relatives use their canines to kill and fix their prey. With the premolars and molars, located on the sides of the jaws, the attacking predator squeezes and “chews” the portion of flesh captured in the mouth.
When carcass cutting, incisors help separate skin and fur from flesh, and powerful lateral teeth of flattened triangular shape cut large pieces of meat. Dogs don’t chew their food long and thoroughly, but they crush bones and crush flesh with their side teeth while eating through powerful chewing motions.
The dog also uses its armed jaws as an effective weapon for attack and defense, which, combined with intense head jerking and high jaw clenching force, can cause serious damage.
The incisors are also used by dogs for hygienic grooming, and for catching fleas that parasitize on the body.
Adult dog dental formula
According to the standard of most breeds, an adult dog should have a full dental formula of 42 permanent teeth.
Thus, on the upper jaw there are:
- 6 incisors (incisivi) – 2 middle, 2 hooks, 2 margins;
- 2 canines (caninus);
- 8 small molars (praemolares);
- 4 molars (molares).
Specialists designate the classical dental formula of the upper jaw of dogs as follows: 2M-4P-1C-3I-3I-1C-4P-2M.
The lower jaw carries 2 more molars (molars) – accordingly, its formula would look like this: 3M-4P-1C-3I-3I-1C-4P-3M.
In the lower jaw, the first molar and in the upper jaw, the premolar, located in front of the first molar, have increased size and are strongly developed, due to which they were called “carnivorous, or predatory, teeth”.
Note that in dogs, quite often there is a reduction of one or more teeth (the so-called “oligodonia”), and most often the premolars or incisors are missing. Sometimes the opposite process – an increase in the number of teeth (polyodontia) – is also encountered. Both are considered a disqualifying defect that excludes the animal from breeding, unless the breed standard otherwise stated.
In particular, hairless representatives of such exotic breed as the Peruvian Naked Dog (Peruvian Inca Orchid) can be practically toothless which is explained by the influence of the specific dominant gene showing absence of body hair and sharp reduction of the number of teeth in the jaws.
So-called brachycephals, i.e. dogs with short muzzles (Pekinese, pugs, bulldogs, etc.) already at a young age (3-5 years) begin to lose their incisors, and by old age most individuals have lost their teeth.
Puppy Dental Formula
Puppies are born blind, deaf and toothless. It is not until the 3rd-4th week of life that teeth erupt. The first teeth that appear are tiny incisors, then the needle-like canines, and finally the premolars. No molars in young puppies, and the dental formula is the same for both the upper and lower jaw, as follows:
Thus, there are 28 milk teeth in a puppy’s mouth before the period of tooth change.
The teeth change between the ages of 3 and 7 months, after which the jaws are shaped to the dental formula of an adult.