Craniomandibular Osteopathy (Swollen Jaw) in dogs

This condition of unknown cause occurs predominantly in young West Highland White Terriers, Scottish Terriers, and Cairn Terriers, and has also been reported in Boston Terriers, Boxers, Labrador Retrievers, Great Danes, and Doberman Pinschers. A recessive mode of inheritance has been described.

The disease begins in puppies 4 to 10 months of age. It is characterized by the deposition of excess bone along the underside of the lower jaw and on other parts of the jaw and skull. The swollen jaw is extremely painful. The hinge joints of the jaw may be involved, making it extremely difficult for the dog to open her mouth. Fever, drooling, and loss of appetite are characteristic. When the mouth is forcefully opened, the dog cries in pain.

Treatment: There is no effective treatment for the abnormal bone deposits. Tube feeding may be required during periods of appetite loss to sup- port nutrition. Pain is controlled with buffered aspirin or other NSAIDs. The disease usually stabilizes at 1 year of age. Partial or complete regression of the excess bone may then occur. Although complete recovery is uncommon, most dogs are able to eat and maintain their weight.

Dogs who have suffered from craniomandibular osteopathy should not be bred. OFA and the GDC maintain craniomandibular osteopathy registries for terriers, in an attempt to diagnose and track the disease.