Assessment and Treatment of Temporomandibular Disorders
Ann-Marie C. DePalma, RDH, BS
Temporomandibular disorders (TMDs) are a variety of disorders affecting the temporomandibular joint (TMJ), its surrounding structures, and the masticatory muscles. The primary muscles of mastication that are involved in TMDs are the masseter, pterygoids, temporalis, and to a lesser extent, the digastric and hyoids (Figure 1). The term TMD commonly refers to the disorders, while TMJ refers to the joint and its supporting structures.
The temporomandibular joint is the articulating junction of the temporal bone of the skull and the condyle of the mandible (Figure 1). Separating the two bones is a cartilaginous material called the meniscus, or disk (Figure 2). The disk is composed of avascular, dense, fibrous connective tissue that separates the joint into upper and lower compartments. The primary motion of the jaw occurs in these compartments. The lower joint space (between the condyle and disk) is where rotation (motion of the jaw on opening) occurs. In the upper joint space (between the disk and the temporal bone), translation occurs. Translation is the gliding forward motion of the jaw that occurs at approximately 25 mm of opening.
A normally functioning jaw will rotate, translate, move side-to-side (lateral excursive movement), and protrude. In a normal closed position, the disk is located on top of the condyle in the glenoid fossa of the temporal bone. Upon opening, the condyle and disk translate (ie, move forward) into the articular eminence. Any deviation of the condyle and disk relationship can result in an internal derangement. Another common type is myofascial pain dysfunction (MPD), which involves pain and limited range of motion (ROM) within the masticatory muscles and surrounding head and neck musculature. Other types of TMDs include degenerative joint diseases (eg, osteoarthritis and rheumatoid arthritis), and less commonly, developmental abnormalities, tumors, and infections.
Symptoms of TMDs vary and mimic many other disorders.1 Symptoms can include "popping," "clicking," limited opening, and pain. Ancillary symptoms such as headaches, earaches, tinnitus, fullness or stuffiness in the ears, dizziness, and shoulder and neck pain have also been reported.
One of the most common types of disorders is an internal derangement. In a reducing joint, the disk is displaced from its normal position on closure, then moves into a normal relationship upon opening of the joint. It may again be displaced upon closing (ie, reciprocal click). In a nonreducing joint, the disk is abnormally placed during closure; when the patient tries to open the joint he or she cannot get "around" the disc (a door-jamb effect). This leads to pain and limited opening.
One diagnostic principle that should be consistently applied is the "look, listen, and feel" approach.2 Looking, listening, and feeling are considered the hallmarks of a proper TMJ evaluation. In about 90% of TMD cases the patients' own description of symptoms, combined with a physical examination and health history, provide information useful in diagnosing these disorders.3 For example, if a patient complains of sharp, shooting pain in front of the ear, this could possibly indicate an internal derangement. If, however, the patient complains of a vague, dull ache along the cheeks and has been diagnosed with bruxism, MPD may be suspected. Listening also involves listening to the joints themselves with a stethoscope, or other amplifying device, to note signs of crepitus, "popping," or "clicking."
Looking at the patient to record a general posture-check can also provide valuable information. Some TMD patients exhibit a forward head posture with rounded shoulders.4 The patient should be examined during function to elicit information regarding ROM and deviation on opening. Any deviation can lead to a preliminary diagnosis. Palpation of the joints and muscles of mastication during all movements should also be performed.
Radiographs are utilized in various roles and phases of TMD diagnosis. A panoramic radiograph gives a basic overview of the dentition and anatomical structures; however, it does not have detailed investigative capabilities for diagnosing TMDs. Transcranial and cross-sectional tomographs provide better diagnostics for TMDs, but they may not be totally beneficial (Figures 3-4-5). In recent years, computed tomography scans and magnetic resonance imaging (MRI) have been utilized. Currently MRI is considered the most accurate and least-invasive imaging technique for examining the TMJ.5 Another diagnostic radiographic modality that can be used is the arthrogram. Due to the invasive nature of this procedure and the advent of less invasive modalities, its use has been decreasing.
Treatment should only be initiated if pain and limited function are exhibited. The treatment for TMDs is surrounded by controversy, and researchers have not been able to identify one treatment or theory as being consistently successful in helping patients. One thing is certain, however, reversible noninvasive procedures should be performed initially.6 These include a soft diet, the application of heat and/or ice to the affected areas, and the limitation of faulty habits (eg, cradling the telephone, gum chewing, excessive singing or talking). The use of pain medications (including opiates and nonopiates), nonsteroidal anti-inflammatory drugs (NSAIDs), and muscle relaxants is also advocated.7 Antidepressant and anti-anxiety medications (in lower doses than psychological dosing), can also be beneficial.6
Other reversible noninvasive forms of therapy include physical and chiropractic therapy, acupuncture, holistic medicine, stress management, psychological counseling, and some nutritional therapies. None of these therapy choices have been scientifically proven to be more beneficial than any other. Most are anecdotal relationships at best, and a multidisciplinary approach is considered most beneficial.6
Appliances are primarily used as splints to stabilize the joints, to decrease clenching or grinding, to decrease inflammation in the joints, and to possibly reposition the disk nonsurgically. If conservative treatments are unsuccessful for a period of three to six months (with the understanding that symptoms may worsen initially, but then gradually improve), it is prudent to reevaluate the patient's needs.2 Since consistent wearing of an appliance over an extended period of time can cause occlusal relationship changes, appliance therapy should only be utilized for short periods and as part of an overall multidisciplinary program.2
Invasive procedures, (ie, occlusal therapy, orthodontics, and surgery) are irreversible and may cause subsequent dilemmas for the patient. Occlusal adjustments have been advocated as a means to decrease occlusal disharmonies that can cause muscle spasms; however, scientific data are contradictory at best.6 In addition, available data are not persuasive that orthodontic treatment either prevents, predisposes to, or causes TMDs.6 As a result, orthodontic treatments, occlusal adjustments, and full-mouth reconstructions are treatment options that should only be considered as finishing stages after the patient has achieved comfort and has adequate ROM. Surgery (eg, arthrocentesis, arthroscopic, laser, or arthrotomy) should only be considered if conservative treatments have failed for a year or more or if there are definitive radiographic osseous changes.2
The Role of the Dental Professional
Patient education is an area in which the hygienist can be most helpful. Dental hygienists can also perform a number of preliminary evaluation procedures, as well as be involved in the more detailed examination and diagnostic process including taking of radiographs and impressions/models as deemed appropriate by practitioner and state practice acts. All patients should be initially screened as part of the intra/extraoral examination, noting ROM and any other obvious signs and symptoms of TMDs.
The comfort of the patient dictates potential treatment, though several basic ideas often helpful for TMD patients include: pre- and postprocedure medications (eg, NSAIDs, muscle relaxants, or prescription pain medications) to relieve inflammation, muscle spasms, and pain; a mouth prop, if needed; stress reduction techniques and cervical or lumbar supports; and transcutaneous electrical nerve stimulation.2
Inadequate oral hygiene can be a result of limited ROM; therefore, placing a patient on a three- to four-month recare is beneficial. The use of small brushes, rubber tips, floss holders, oral irrigators, and automated toothbrushes can be recommended during maintenance. Depending on the type of appliance material, the patient should be instructed to soak the therapeutic appliance in commercial denture cleaners and/or brush daily with a soft brush and toothpaste.1
The hygienist should maintain the patient's record so that the contact information for all treatment practitioners is listed. Current notations of the patient's progress and treatments should be available.2
It has been stated that there are "significant problems with current diagnostic classification systems of TMDs. There is no clear consensus within the practicing community as to what, how, and if TMD problems should be treated. The most promising approaches to management and treatment of TMDs should be evidence-based and patient-centered. Professional education is needed to ensure proper and safe practice in the treatment of TMDs."6 The role of the hygienist is an important aspect of these conclusions. Hygienists need to increase their knowledge in the controversial field of TMDs to aid and educate those patients who are experiencing this disease.
*Clinical dental hygiene practice, Wakefield, MA.
- DePalma AM. The dental situation. RDH 1997;17(10):34.
- DePalma AM. Temporomandibular disorders. Access 1993;7(7):24-28.
- TMD, Temporomandibular Disorders. Bethesda, MD: National Institute of Dental Research, National Institutes of Health publication; 94-3487.
- Andrew-Hebert L. Overcoming TMJ. IMPACC-USA Publishers; 1996.
- Bell WE. Temporomandibular Disorders: Classification, Diagnosis, and Management. Yearbook Publishing; 1990.
- National Institutes of Health Technology Assessment. Management of Temporomandibular Disorders. Paper presented at: National Institute of Dental Research; April 29-May 1, 1996; Bethesda, MD.
- Okeson J. Management of Temporomandibular Disorders. St. Louis, MO: Mosby; 1989.