A Temporomandibular joint disorder (TMJ) is an acute or chronic inflammation of the temporomandibular joint (the joint connecting the lower jaw to the skull). The disorder and resultant dysfunction results in significant pain and impairment for many. There have been multi-factorial approaches gleaned out of thousands of clinical studies. These have been based mostly on empirical evidence. Attempts in the last decade to suggest surgical treatment modalities based on MRI and CAT scan parameters now receive less attention. These techniques are reserved for the most recalcitrant cases where other therapeutic modalities have changed. Exercise protocols and habit control have in my experience of 35 years in oral surgery appear to be the first line of approach. Certainly a focus on other possible causes of facial pain and jaw immobility and dysfunction should be the initial consideration of the examining oral surgeon or well-trained health professional. It is suggested that before the attending doctor commences any plan of approach utilizing medications or surgery a thorough search for inciting para-functional jaw habits must be performed. Correction of any discrepancies from normal can then be the primary goal.
An approach to eliminating para-functional habits involves the taking of a detailed history and careful physical examination. The medical history should be designed to reveal duration of illness and symptoms, previous treatment and effects, contributing medical findings, history of facial trauma and a search for habits that may have produced or enhanced symptoms. Particular attention should be directed in identifying perverse jaw habits such as clenching or teeth grinding, lip or cheek biting, or positioning of the lower jaw in an edge to edge bite. All of the above puts strain of the bilateral external pterygoid muscles and resultant jaw pain. Palpation of these muscles will cause a painful response.
There are many external factors that place undue strain on the TMJ. These include but are not limited to the following:
Over-opening the jaws beyond their range for the individual or unusually aggressive or repetitive sliding of the jaws sideways (laterally) or forward (protrusive). These movements may also be due to perverse habits or a malalignment of the jaws or dentition. This may be due to :
- Speech habits resulting in jaw thrusting.
- Excessive gum chewing or nail biting.
- Excessive jaw movements associated with exercise.
- Size of foods eaten.
- Sexual activity.