The shape of an animal's skull has an effect on the shape of his jaws. When the jaw is shortened, as it is in the case of brachycephalic animals, the teeth have less room in which to grow. But the brachycephalic animal has the same number of teeth as other animals of his species, so those teeth grow in crowded. They can stick out in odd directions, and they can make it difficult for the animal to chew.
Types of Muzzles
There are three types of muzzles. Brachycephalic muzzles are short and wide, pushed in or flat in appearance. Mesaticephalic muzzles are of medium length and width. Dogs such as golden retrievers and terriers fall into this category. The third type is dolichocephalic, whereby the muzzle is long and narrow. Oriental cats, such as the Siamese, and dogs like Doberman pinschers and greyhounds are dolichocephalic. Of the three, the brachycephalic animal is the most likely to have dental troubles.
Normal Amount of Teeth
Dogs have 42 teeth, and when the teeth are in the correct order and position, they work well. But when the jaw is short, those teeth get crammed in there tightly. The result is teeth that stick out at right angles or grow inward toward the roof of the mouth. This results in food getting stuck between teeth or shoved up into the gums, creating infection and gum disease, and eventual tooth loss if allowed to continue.
In dogs, the deciduous teeth emerge at 3 to 4 weeks of age. The permanent teeth erupt at 3 to 4 months. Normally, the deciduous teeth are shed, leaving room for the new teeth. In brachycephalic dogs, it's common for the deciduous teeth to become so cramped that they remain, resulting in permanent teeth that don't erupt. There are more permanent teeth than just the deciduous, so if the baby teeth can't fit in the dogs' mouth, the adult teeth definitely won't.
Treatment of Crowded Teeth
If the deciduous teeth don't come out due to overcrowding, those extra teeth need to be surgically removed, along with an appropriate amount of permanent teeth, so the remaining ones can space out as they should and fit properly in the mouth. The veterinarian will determine which teeth need to come out and will likely concentrate on teeth that are inappropriately placed. Teeth that are sideways, for example, will just cause trouble if they remain.