There are many different types of jawbone disorders that can be problematic in a variety of dogs from the small little toy dogs on up to the giant dogs. Some breeds will have possible jawbone problems either based on genetic or congenital problems that can occur within the breed or line. By purchasing a puppy through a reputable breeder there is far less chance of any type of jawbone abnormality to occur, plus you will have researched the breed and be aware of the potential problems and issues that can occur.
In most breeds there is the possibility of an under or overshot jaw. In some breeds, such as the Bulldog, the longer lower jaw is desirable, but in most breeds it is considered a serious fault or a disqualification. Dogs with longer lower jaws may have increased problems with trauma and damage to the jaw that can affect the movement of the mouth. Since any pain associated with the mouth or jaw leads to a decrease in food consumption, this can have a huge impact on the overall health of the dog.
In some breeds, such as the Great Dane, Scottish Terrier, West Highland White Terrier, Cairn Terrier, Boston Terrier, Boxer and Doberman Pinscher, a condition known as craniomandibular osteopathy is a serious problem. This is a genetic condition caused by a recessive gene that causes the bones of the head and lower jaw to thicken, which in turn causes the dog pain when eating or moving the jaw. Typically this condition is first noted when the puppy is about four to eight months and all that can be done for treatment is pain medicine therapy and steroids if needed. Usually the condition will reverse itself when the dog is about a year old, although some dogs have permanent problems with eating and must be fed special diets.
Masticatory muscle myositis is another disease of the mouth that affects the muscles that control the jaw, causing the dog to have difficulty in moving the jaw and will eventually result in the muscles shrinking preventing the dog from opening his or her mouth. This condition is not a jawbone disease as such, rather it is another of the auto-immune disorders and does respond well to anti-inflammatory and immune drug therapy treatments. The symptoms include a swollen area around the jaw as well as a reluctance or pain in opening the mouth. German Shepherds, English Pointers and Springer Spaniels are occasionally seen with the disorder.
Overshot jaws occur when the top jaw is much longer than the bottom jaw, resulting in misalignment of the teeth. This condition can lead to serious digestive problems for the dog as the food is not properly chewed or broken up by the teeth. In most cases dogs with serious overshot or undershot jaws are not used in breeding programs although they will make ideal pets and lovable companions.
In any dog with a jawbone problem or bite irregularity feeding the best possible high quality food will be important, especially if chewing is impaired or eating is difficult. Always discuss your feeding options with your vet if the dog has had any trauma or injury to the jaw or has a genetic or congenital jawbone malformation.