Facial pain syndrome


  1. Classification of facial pain syndromes
  2. Aetiology
  3. Atypical facial pain
  4. Trigeminal neuralgia
  5. Other facial pain syndromes

Classification of facial pain syndromes

Idiopathic (unknown cause) facial pain makes up a significant proportion of oral and maxillofacial practice. In 1994 the International Association for the Study of Pain revised its classification of chronic pain. This now includes:

Idiopathic facial pain is a very real entity and not just a manifestation of psychological problems, although they are sometimes associated. All forms should remain a ‘diagnosis of exclusion’ (that is, all other causes of facial pain, notably arising from the teeth, sinuses, neuralgias and headaches should be considered and if necessary investigated). A thorough medical history and examination needs to include examination of the cranial nerves. In selected cases CT or MRI scans may be necessary to exclude serious pathology. This is important as vague pain can on occasion be a symptom of a life-threatening disease, particularly when conventional treatments fail. Periodic reassessment is also advisable for this reason. Occasionally some forms of idiopathic facial pain (for example, oral dysaesthesia ) are associated with deficiencies in iron, vitamin B12 or folic acid.


It has been suggested that facial-pain symptoms may be interrelated and form part of a whole body pain syndrome involving the neck, back, abdomen and skin. Adverse life events, ‘stress’ and impaired coping ability are the strongest known associated factors.

The aetiology of idiopathic facial pain is (by definition) unknown - the physiology of pain is very complicated. In temporomandibular joint pain dysfunction syndrome evidence suggests that stress-induced inflammation within and around the joint can cause local production of various chemicals, including free radicals, which results in pain and in possibly destructive changes to the joint. Some of these chemicals may also develop in muscles and teeth, accounting for the different anatomical locations for pain. Neuropeptides have been demonstrated within the temporomandibular joint capsule. Free radicals, in addition to causing pain, may also have an effect on the synovial fluid (lubricating fluid in the joint), impairing its lubricating ability and resulting in adhesions across the joint. Other pain mediating agents (including 15-hydroxyeicosatraeinoic acid, 15-HETE, and ‘substance P’, a neuropeptide) have been identified. It has been suggested that these chemicals may be present in other nerve endings, which may help to account for dental-type pain in the absence of obvious dental disease (odontalgia; see below).

Atypical facial pain

This is pain which does not fit into any other diagnostic categories (such as diseases of the teeth, sinuses, ear, jaw joint, etc.). It is essentially a diagnosis of exclusion.

Atypical facial pain is often characterised by its bizarre and inconsistent nature. Symptoms may be related to those of atypical odontalgia (see below) which, it has been suggested, is a localised variant of atypical facial pain. It may be described as an intense, deep, constant burning or aching pain. It is usually difficult to localise the pain. As a rule of thumb, organic pain (due to infection, trauma, tumours, nerve irritation etc.) does not cross the midline of the face. Despite the severity of the symptoms, patients are not kept awake at night by the pain. Other symptoms (such as dysaesthesia (distorted sensation), paraesthesia (lack of sensation), tingling and numbness may be experienced. There has to be careful assessment to make sure there is no underlying disease such as multiple sclerosis or tumours. Similar to temporomandibular joint pain dysfunction syndrome, stress, anxiety and depression are often associated with atypical facial pain.

Trigeminal neuralgia

Trigeminal neuralgia (tic douloureux) is described as ‘a painful unilateral affliction of the face, characterised by brief electric shock-like (lancinating) pains, limited to the distribution of one or more divisions of the trigeminal nerve’. Typically it occurs in middle aged and elderly patients. The second and third divisions of the trigeminal nerve (mainly in the region of the upper and lower jaws) are usually affected. Episodes may occur occasionally or frequently over several weeks to months, often followed by pain-free intervals. Patients describe the pain as like a sudden electric shock, frequently triggered by trivial stimuli of the face, such as with washing, shaving, chewing and talking. It may also occur spontaneously.

Other facial pain syndromes



Periapical periodontitis and abscess

Atypical odontalgia

Glossodynia and sore mouth (also known as ‘burning mouth syndrome’ or ‘oral dysaesthesia’)

Cracked tooth syndrome

Trigeminal herpes zoster

Postherpetic neuralgia

Secondary neuralgia from central nervous system lesions

Glossopharyngeal (affecting tongue and throat (pharynx)) neuralgia

Further reading: Diagnosis