Article by John Miller
What Causes TMJ?
TMJ dysfunction is considered a multifaceted musculoskeletal disorder.
The most common causes of TMD include:
- Masticatory muscle dysfunction,
- Derangement/displacement of TMJ articular disc
- Bruxism: nocturnal grinding of teeth leads to increased pressure in TMJ and asymmetrical movement.
- Occlusal Problems: Poor bite, Asymmetrical or Retrognathic (underbite, overbite).
Contributory factors include:
- Mandibular malalignment is secondary to an occlusal appliance or orthodontic treatment.
- Removal of wisdom teeth,
- Prolonged mouth opening, e.g. dental procedure,
- Poor cervical posture,
- Myofascial pain,
- Neuropsychological factors,
- Stress and
- Whiplash and other less common causes include trauma (e.g., blow to the chin), infection, polyarthritic conditions, tumours, and anatomical abnormalities.
TMJ Dysfunction Classifications
The common presentations of TMJ dysfunction classify into three clinical diagnostic groups:
- Jaw muscle disorder is characterised by painful movement.
- Articular disc displacement.
- Arthralgia or arthritis.
(Dworkin SF, LeResche L., 1992)
What is the Cause of Jaw Clicking?
A clicking of the jaw is a sign of articular disc displacement, which is commonly treated by a TMJ physiotherapist. Clicking can occur during jaw opening, closing or both directions. Please seek the clinical assessment of a TMJ physiotherapist for a specific diagnosis and treatment plan.
Common Sources of TMJ Dysfunction or Jaw Pain
TMJ or jaw pain can occur as a result of various multi-factorial reasons. Most TMJ dysfunction resulting in jaw pain or clicking jaw results from two leading causes: jaw opening or closing.
TMJ Dysfunction - Abnormal Opening
Most TMJ dysfunction that occurs results in an inability to open your jaw fully or symmetrically. Luckily nearly all opening dysfunctions respond exceptionally quickly and favourably to physiotherapy assessment and intervention since teeth occlusion is not an issue.
TMJ Dysfunction - Abnormal Closing
Closing dysfunction can be due to both a teeth occlusion and an inability of the TMJ to close normally. If the problem is simply a stiff joint or poor muscle timing, then physiotherapy treatment will be very successful. However, if teeth occlusion issues exist, then you will be referred to a dental surgeon for a bite occlusion assessment.