Paralysis of the Jaw in Dogs

Trigeminal Neuritis in Dogs

Sudden onset of the inability to close the jaw owing to dysfunction of the mandibular (jaw) branch of the trigeminal nerves (one of the cranial nerves) is a treatable medical condition called trigeminal nerve neuritis (inflammation). This is often due to nerve injury, which ranges from neuritis, demyelination (loss of the fatty sheath around the nerve which helps conduct the signal), and sometimes to fiber degeneration of all the branches of the trigeminal nerve and the nerve cell body.

Although it is occasionally seen in cats, trigeminal neuritis is mainly an illness of dogs.

Symptoms and Types

• Acute onset of a dropped jaw
• Inability to close the mouth
• Drooling
• Difficulty in getting food in the mouth
• Messy eating
• No loss of feeling in the jaw or face
• Swallowing remains normal                 

Causes

The underlying cause of trigeminal nerve neuritis is currently uknown, though it is possibly immune-mediated.

Diagnosis

Your veterinarian will perform a thorough physical exam on your dog, taking into account the background medical history, onset of symptoms and possible incidents that might have led to this condition. Your veterinarian will order a blood chemical profile, a complete blood count, a urinalysis and an electrolyte panel to rule out other diseases. Rabies is one of the more important disease conditions that will need to be ruled out. Diagnostic imaging like X-ray will be used to examine the skull and jaw bones, and bone marrow core biopsies and muscle biopsies can be used to rule out other possibilities for disease.