Temporomandibular Joint Disorders JENNIFER J. BUESCHER, MD, MSPH, Clarkson Family Medicine Residency, Omaha, Nebraska Temporomandibular joint disorders are common in adults; as many as one third of adults report having one or more symptoms, which include jaw or neck pain, headache, and clicking or grating within the joint. Most symptoms improve without treatment, but various noninvasive therapies may reduce pain for patients who have not experi- enced relief from self-care therapies. Physical therapy modalities (e.g., iontophoresis, phonophoresis), psychological therapies (e.g., cognitive behavior therapy), relaxation techniques, and complementary therapies (e.g., acupuncture, hypnosis) are all used for the treatment of temporomandibular joint disorders; however, no therapies have been shown to be uniformly superior for the treatment of pain or oral dysfunction. Noninvasive therapies should be attempted before pursuing invasive, permanent, or semi- permanent treatments that have the potential to cause irreparable harm. Dental occlusion therapy (e.g., oral splinting) is a common treatment for temporomandibular joint disorders, but a recent systematic review found insufficient evidence for or against its use. R ME Some patients with intractable temporomandibular joint disorders os D H develop chronic pain syndrome and may benefit from treatment, loy including antidepressants or cognitive behavior therapy. (Am Fam Physician 2007;76:1477-82, 1483-84. Copyright © 2007 American Academy of Family Physicians.) ILLUSTRATION BY F ▲ Patient information: emporomandibular joint (TMJ) change and regenerate itself than the hya- A handout on temporo- disorder refers to a cluster of con- line cartilage of other synovial joints.5 The mandibular joint pain, ditions characterized by pain in synovial joint capsule and surrounding mus- written by the author of this article, is provided on the TMJ or its surrounding tissues, culature are innervated, however, and are page 1483. T functional limitations of the mandible, or thought to be the primary source of pain in clicking in the TMJ during motion.1,2 TMJ TMJ disorders. disorders are common and often self-limited The etiology of TMJ disorders remains in the adult population. In epidemiologic unclear, but it is likely multifactorial. Cap- studies, up to 75 percent of adults show at sule inflammation or damage and muscle least one sign of joint dysfunction on exami- pain or spasm may be caused by abnormal nation and as many as one third have at least occlusion, parafunctional habits (e.g., brux- one symptom.2,3 However, only 5 percent of ism [teeth grinding], teeth clenching, lip adults with TMJ symptoms require treatment biting), stress, anxiety, or abnormalities and even fewer develop chronic or debilitat- of the intra-articular disk. In recent years, ing symptoms.4 many of the theories about the develop- ment of TMJ disorders have been ques- Etiology tioned. Abnormal dental occlusion appears The TMJ is a synovial joint that contains an to be equally common in persons with articular disk, which allows for hinge and and without TMJ symptoms,1,6 and occlu- sliding movements. This complex combina- sal correction does not reliably improve tion of movements allows for painless and the symptoms or signs of TMJ disorders.2,7 efficient chewing, swallowing, and speak- Parafunctional habits have been thought ing.5 The articulating surfaces of the TMJ to cause TMJ microtrauma or masticatory are covered by a fibrous connective tissue; muscle hyperactivity8; however, these habits this avascular and noninnervated structure are also common in asymptomatic patients. has a greater capacity to resist degenerative Although parafunctional habits may play a Downloaded from the American Family Physician Web site at www.aafp.org/afp. Copyright © 2007 American Academy of Family Physicians. For the private, noncommercial use of one individual user of the Web site. All other rights reserved. Contact [email protected] for copyright questions and/or permission requests. TMJ Disorders SORT: KEY RECOMMENDATIONS FOR PRACTICE Evidence Clinical recommendation rating References TMJ disorders can be associated with other chronic pain syndromes or C 8 mental illness. Complicated cases may benefit from a multidisciplinary approach. TMJ disorders are commonly self-limited and should initially be treated C 16 with noninvasive therapies. Permanent occlusal adjustment and temporary dental splinting have not B 2, 7 been sufficiently studied to indicate benefit or harm for patients with TMJ disorders. TMJ = temporomandibular joint. A = consistent, good-quality patient-oriented evidence; B = inconsistent or limited-quality patient-oriented evidence; C = consensus, disease-oriented evidence, usual practice, expert opinion, or case series. For information about the SORT evidence rating system, see page 1435 or http://www.aafp.org/afpsort.xml. role in initiating or perpetuating symptoms in trigger points may be determined by palpa- some patients, the cause-and-effect relation- tion of the masseter or sternocleidomastoid ship remains uncertain.8 muscles,9 which can be performed by plac- There is some evidence to suggest that ing a finger over the TMJ or into the ear anxiety, stress, and other emotional distur- canal while the patient opens and closes bances may exacerbate TMJ disorders, espe- the mouth. A clicking or popping sensation cially in patients who experience chronic that occurs during mouth opening may pain.8 As many as 75 percent of patients with indicate displacement of the intra-articular TMJ disorders have a significant psychologi- disk during mandibular movement.10 Pain cal abnormality.8 Recognition and treatment or swelling localized to the TMJ can indicate of concomitant mental illness is important intra-articular inflammation. Clicking is a in the overall approach to management of common symptom and is part of the diag- chronic pain, including pain caused by TMJ nostic criteria for TMJ disorders; however, disorders. joint sounds do not necessarily correlate with pain severity or functional limitation. Diagnosis Therefore, the absence of clicking sounds CLINICAL eXAMINATION is not a reliable symptom to use in deter- Common symptoms of TMJ disorders mining whether the patient has responded include jaw pain, limited or painful jaw to treatment.8 Absence of pain, improved movement, headache, neck pain or stiff- function, and normal quality of life are more ness, clicking or grating within the joint, appropriate markers of treatment success. and, occasionally, an inability to open the mouth painlessly.2,4 Most adults with these DIFFERENTIAL dIAGNOSIS symptoms do not seek medical or dental The differential diagnosis for orofacial pain is treatment. It is not clear which symptoms are listed in Table 1.4,11 TMJ disorders can cause more common in which TMJ disorders; how- referred pain, particularly undifferentiated ever, it is generally assumed that joint clicking headache.8 Some studies have shown that as or grating signifies intra-articular derange- many as 55 percent of patients with chronic ment whereas headache, neck pain, or painful headache who were referred to a neurologist jaw movement suggests a muscular problem. were found to have significant signs or symp- Examination of the TMJ and masticatory toms of TMJ disorders.12 Educating patients muscles should include careful palpation of on self-care techniques and referral for non- all structures. Myospasm and myofascial invasive treatment should be considered in 1478 American Family Physician www.aafp.org/afp Volume 76, Number 10 ◆ November 15, 2007 Table 1. Differential Diagnosis of Orofacial Pain Condition Symptoms Signs Dental pathology Tooth abscess Pain with chewing over Visible tooth decay; fluctuance along gum affected tooth line; pain with palpation over the tooth Wisdom tooth eruption Dull ache behind posterior Tenderness to palpation over emerging molars tooth Infection or inflammation Herpes zoster and Prodrome of pain followed Vesicular rash in dermatomal postherpetic neuralgia by vesicular rash distribution, not crossing midline Mastoiditis Fever; otalgia Postauricular erythema and swelling; tenderness over mastoid process Otitis externa Pruritus, pain, and tenderness Erythema and edema of external of the external ear auditory canal Otitis media Fever; malaise; otalgia Tympanic membrane dull, bulging, erythematous; loss of landmarks on tympanic membrane Parotitis Fever; malaise; myalgia; pain Tenderness and induration over parotid over parotid gland gland Sialadenitis Pain and swelling of involved Tenderness, induration, and/or erythema salivary gland of salivary gland; usually unilateral Trigeminal neuralgia Paroxysmal, unilateral Examination generally normal lancinating pains in trigeminal nerve distribution Information from reference 4 and 11. patients with chronic undifferentiated head- origin of the problem: articular disorders ache or headache that is not responding to and masticatory muscle disorders. Articu- standard treatment. lar disorders include the articular surface, intra-articular disk, or articulating bones.8,11 CLASSIFICATION Masticatory muscle disorders are problems Research has been hindered by the lack of within the muscles surrounding the TMJ. clear diagnostic criteria for TMJ disorders; Accurate recognition of the origin of pain, however, two groups have developed diag- either intra-articular or muscular, may help nostic classification systems. The American the physician recommend an initial therapy; Academy of Orofacial Pain published