Your doctor will ask about your symptoms and your medical history, including any history of multiple sclerosis, a condition that may cause similar or even identical symptoms. To help rule out medical and dental conditions that can have similar symptoms, your doctor also will ask whether you have a history of:
Recent trauma to your face or teeth
A recent tooth infection or root canal treatment
A tooth extraction on the same side as your facial pain – Sometimes a tooth extraction can cause pain in the area of the missing tooth.
Any areas of painful facial blisters – Painful blisters can be a sign that you have a viral infection involving your facial skin, such as herpes (which is caused by the herpes simplex virus) or shingles (which is caused by varicella zoster, the chickenpox virus). Facial pain can last for weeks after the blisters heal, especially in cases of shingles.
Next, your doctor will thoroughly examine your head and neck, including the area inside your mouth. The doctor also will do a brief neurological examination and concentrate on feeling and muscle movements in your face. In almost all cases of trigeminal neuralgia, the results of these examinations are normal. If necessary, your doctor will order a magnetic resonance imaging (MRI) or computed tomography (CT) scan of your head to check for blood vessel abnormalities, tumors pressing on your trigeminal nerve or other possible causes of your symptoms.
Your doctor will diagnose trigeminal neuralgia based on your symptoms, the examination and test results. There is no specific test to confirm the diagnosis of trigeminal neuralgia, so an important part of the diagnosis is excluding other explanations for the symptoms.