Trigeminal neuritis is a condition which refers to sudden onset of inability of a dog to open or close its jaws owing to dysfunction of mandibular branch of the trigeminal nerves. Also known as mandibular paralysis, the condition is relatively rare. It affects It affects the trigeminal nerve, which wraps around the face, controlling functions like a dog's blinking reflex and movement of the lower jaw. One of the most common symptoms in a dog with trigeminal neuritis is a "dropped jaw," where the dog's lower jaw is always slightly open.
This condition 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. The dog often exhibits abnormal mandibular coordination and sensation, but in the early stages, the animal does maintain some control of the jaw. This condition is temporary in most cases and supportive care is key to helping a dog with TN. It can happen to any dog and there is no age, sex or breed predisposition.
Common symptoms associated with trigeminal neuritis are:
Acute onset of a dropped jaw
Inability to close the mouth
Difficulty in getting food in the mouth
No loss of feeling in the jaw or face
Swallowing remains normal
Inability to blink eyes