Your dog, just like his human counterparts, has a temporomandibular joint—two, actually, one on each side of his jaws—that is responsible for the opening and closing of his jaws. Oftentimes this joint is referred to as "TMJ" and sometimes disorders can arise in the jaw joint, causing pain and discomfort during eating.
The temporomanibular joints work in conjunction with one another and are positioned where the mandible and maxilla (the lower and upper jaws) meet one another. The joints are vital for normal, everyday actions such as chewing and simply opening and closing the mouth. A disk that sits inside each joint is responsible for proper rotation of the jaws. Sometimes the disk can be thrown out of place, causing pain and trouble chewing. The condyle and fossa, which are also important parts of the TMJ that work to allow the disk to rotate, may also develop dislocation problems.
TMJ Disorder Symptoms
Since animals are unable to verbally tell us something is causing them discomfort, being in tune with your canine buddy is an important part of ensuring a high quality of life for him. Dogs who experience difficulty chewing their food or opening and closing their mouths may be experiencing TMJ issues. Scratching or pawing at his face may indicate that he's experiencing pain there. He may whine or vocalize while he eats—though this may be perplexing at first, it's possible that it's actually painful for him to chew his food. He may lose his appetite altogether because chewing is simply too much trouble and pain. Any breed of dog can experience issues in the TMJ, but basset hounds have been noted to be more prone to the disorder, according to petMD. Lockjaw, or open-mouth mandibular locking, has been observed in basset hounds and Irish setters.
Causes of TMJ Disorder
If your dog has experienced any type of trauma to the sides of his jaws, this could set the groundwork for TMJ pain and discomfort. The joint is quite fragile: if it is traumatized, the disk can be knocked out of place. Many dogs love to carry multiple toys in their mouths at once, which usually doesn't hurt them. However, heavy toys or objects can place stress on the jaw joint and lead to possible TMJ problems.
Diagnosis and Treatment
A veterinarian will need your dog's full medical history. Make sure to tell her about any problems your dog is experiencing. A full physical examination of the mouth will be necessary. Blood tests, a urinalysis and a biochemistry profile may also be necessary. X-rays are often key in helping a veterinarian pinpoint any TMJ problems. Magnetic resonance imaging (MRI) may be necessary for a clearer look at the joints. TMJ disorders in both dogs and humans are notoriously difficult to treat. In certain cases, surgery may be recommended. Surgical methods of TMJ may be used to accomplish different things depending on the location of the disc inside the joint. A veterinarian may recommend a soft diet for dogs living with TMJ to prevent overworking the joints. A nonsurgical approach to treatment, where a veterinarian places an object close to the joint and attempts to gently close the dog's mouth while using an instrument to push the joint back into place, may also be used.
By Pamela Miller
petMD: Temporomandibular Joint Disorders in Dogs
Veterinary Radiology and Ultrasound: Magnetic resonance imaging features of the temporomandibular joint in normal dogs
My Pet Dentist: Temporomandibular joint (TMJ) problems
About the Author
Pamela Miller has been writing for health, beauty and animal health/welfare publications for seven years. Miller holds a Bachelor of Science in Organizational Communication from MTSU.