Diagnosing facial pain
What to look for in a case of long-term facial pain
A 36-year-old female presents with a six-month history of left-sided facial pain. The pain is sporadic in nature and the character is described as both dull and occasionally sharp, located over the cheek and jaw and occasionally crossing over to the right side of the face. It is present throughout the day but not when sleeping and is not related to chewing or eating. The patient reports no previous toothache but has had multiple dental treatments and tooth extractions that haven’t helped the pain. The past medical history includes depression and chronic lower back pain.
With such a complex anatomical structure, facial pain can be a confusing presentation. The top five causes are:
- Jaw joint
- Neuropathic – trigeminal neuralgia
- Persistent idiopathic or ‘atypical’ facial pain (AFP)
- More rarely, a bone cyst or tumour
It is useful for the clinician to note that most of these diagnoses have a distinct history and pattern. From our experience, the difficult patients to diagnose and treat are those presenting with neuropathic or ‘atypical’ presentations.
More than 90% of orofacial pain is dental in origin, yet many patients present to their GP rather than a dental surgeon. Toothache generally progresses from an acute sharp sensitivity to a longer-lasting dull ache and then on to dental sepsis, which may result in acute facial swelling. Many will present to the GP and will not have a regular dentist.
Dental pain is often localised to a tooth or area, and there may also be clues as to previous dental pain in the same area. The pain will be severe and throbbing in character, lasting minutes to hours, often made worse by hot or cold food or drink and by biting on that side. If you suspect a dental cause, asking the patient to visit their dentist is appropriate.
A brief oral examination, looking for visible dental decay near the location of the pain, may provide the answer. Does pressing on the teeth with a tongue spatula cause pain? Is there gum redness or swelling near the teeth? These signs will further point to a dental cause. The rest of this article focuses on the more unusual presentations of facial pain.
The presentation and management of salivary disease, such as obstruction, will be familiar and is not discussed in detail here. Symptoms of ‘mealtime syndrome’ and swelling in the region of a salivary gland are usually pathognomonic of duct obstruction. There is potential for confusion and overlap of jaw joint pain with chronic or atypical facial pain.
In the case presented, the patient’s history does not suggest any of these pain patterns. The pain is both dull and sharp in character and appears sporadic in nature, not linked to teeth, jaw joint or other exacerbating factors. The most likely differential diagnoses would be neuralgic facial pain such as trigeminal neuralgia or AFP. Several factors from the history exclude trigeminal neuralgia:
- The pain is not associated with a trigeminal dermatome and crosses the midline of the face
- There are no obvious physical causative factors or facial ‘trigger zones’
- The pain varies in character, unlike the characteristic ‘electric shock’ excruciating pain of trigeminal neuralgia
Several points in the history make AFP more likely. There is a strong association between AFP, psychiatric illness such as depression and anxiety and other chronic pain syndromes, such as fibromyalgia, back pain, IBS, as found with the presentation. AFP patients may have sought dental treatment in the past or have misdiagnoses of neuropathic pain. On occasion, teeth have been extracted with no improvement.
A good starting point in the consultation is to ask the patient to map out where the pain occurs. A random pattern or lack of clarity regarding location and tissue depth will heighten suspicion. When you examine this patient you are aiming to exclude a possible organic cause for the pain. Assess the dermatome distribution, look at the teeth, examine the temporomandibular joint (TMJ) and palpate the muscles of mastication to exclude myofascial pain syndrome.
Other variants of chronic orofacial pain syndromes include burning mouth syndrome and atypical odontalgia. Oral dysaesthesia, or ‘burning mouth syndrome’ classically presents as oral pain (mostly in the tongue), altered taste (metallic, oil or fish in nature) and a subjective xerostomia. Atypical odontalgia is chronic dental pain despite there being no obvious dental pathology or treated dental pathology but continuous pain. Management of these is similar to AFP, as discussed below.
You should always be aware of red flag or ‘sinister’ features that may suggest an urgent cancer referral. These include associated swelling or oral ulceration, and lymphadenopathy.1
Investigation and management
AFP is a diagnosis of exclusion, and it may be difficult in general practice to confidently exclude all other causes. This group of patients may often have seen several practitioners and specialists. Referral on a routine basis is appropriate for a patient in whom AFP is suspected or the diagnosis is uncertain.
Investigations will include a dental X-ray and possibly an MRI scan to exclude a space-occupying lesion, demyelinating disease or TMJ pathology. First-line treatment for all chronic orofacial pain syndromes is a tricyclic antidepressant such as amitriptyline or nortriptyline. SSRIs can also be effective. Anticonvulsants such as carbamazepine, gabapentin or pregabalin are second-line therapy for AFP. There is no strong evidence that psychological therapy is beneficial in chronic orofacial pain syndromes.
Mr Karl Payne, Mr Alex Goodson and Mr Arpan Tahim are specialty registrars in maxillofacial and head and neck surgery. Professor Peter Brennan is a consultant in maxillofacial and head and neck surgery, all at the Worcestershire Royal Hospital
- Goodson A, Payne K, Tahim A et al. Important Oral and Maxillofacial Presentations for the Primary Care Practitioner 2016; Libri Publishers ISBN 10: 1909818933 ISBN 13: 9781909818934.
The authors have recently published Important Oral and Maxillofacial Presentations for the Primary Care Clinician, which has been sent to every GP practice in the UK free of charge. It contains algorithms and guidance for the management of many head and neck conditions including lumps and malignant disease. The book was written in collaboration with the RCGP. Further copies are available at cost price (£12.50) from Amazon.