> Table of Contents > Temporomandibular Joint Disorder (TMD)
Temporomandibular Joint Disorder (TMD)
Benjamin N. Schneider, MD
Jessica Johnson, MD, MPH
image BASICS
DESCRIPTION
  • Syndrome characterized by
    • Pain and tenderness involving the muscles of mastications and surrounding tissues
    • Sound, pain, stiffness, or grating in the temporomandibular joint (TMJ) with movement
    • Limitation of mandibular movement with possible locking or dislocation
    • Recent research suggests that TMD is a complex disorder with multiple causes consistent with a biopsychosocial model of illness (1)[B].
  • System(s) affected: musculoskeletal
  • Synonym(s): TMJ syndrome; TMJ dysfunction; myofascial pain-dysfunction syndrome; bruxism; orofacial pain
EPIDEMIOLOGY
Incidence
  • Symptoms more common in ages 30 to 50 years
  • Predominant sex: female > male (4:1)
Prevalence
  • General prevalence is 6-12% in both adults and older children. Up to 1/2 the population has at least one sign or symptom of TMD, but most are not limited by symptoms, and < 1:4 seek medical or dental treatment.
ETIOLOGY AND PATHOPHYSIOLOGY
  • Pathophysiology is multifactorial, involving anatomic, behavioral, emotional, and cognitive factors.
  • The American Academy of Orofacial Pain categorizes TMD according to three anatomic origins of pain and the change in name from TMJ to TMD emphasizes that many patients suffer from muscular and not articular pain.
  • Cranial bone disorder including the mandible
    • Congenital and developmental disorders
    • Acquired disorders (fracture, neoplasm)
  • Articular disorders of the joint
    • Congenital disorders
    • Inflammatory disorders: synovitis, arthritides, capsulitis, ankyloses
    • Avascular necrosis (rare)
    • TMJ disk derangement, osteoarthritis
    • Hyper- or hypomobile TMJ
    • TMJ trauma: condylar fractures, dislocation
  • Muscle disorders involving the muscles of mastication
    • Occlusomuscular dysfunction (bruxism)
    • Masticatory muscle spasm
    • Myositis
    • Myofibrosis
    • Poorly fitting oral devices (dentures, splints, etc.)
    • Contracture
    • Neoplasia
Genetics
Research is ongoing in gene polymorphisms associated with TMD and other pain disorders. These include the catechol O-methyltransferase gene (COMT), which is thought to be associated with changes in pain responsiveness.
RISK FACTORS
  • Macrotrauma to the face, jaw, and neck, including cervical whiplash injuries and hyperextension of jaw
  • Rheumatologic and degenerative conditions involving the TMJ
  • Psychosocial stress and poor adaptive capabilities
  • Repetitive microtrauma from dental malocclusion, including inappropriate dental treatment.
  • Link with bruxism and jaw/teeth clenching is inconsistent.
GENERAL PREVENTION
  • Elimination of tension-causing oral habits
  • Reduction in overall muscle tension
COMMONLY ASSOCIATED CONDITIONS
Craniomandibular disorders, somatization disorder, somatoform pain disorder, other chronic pain syndromes, fibromyalgia, juvenile idiopathic arthritis, tension headache, sleep disturbance, tobacco use
image DIAGNOSIS
  • TMD is a clinical diagnosis, and localized pain is the unifying feature.
  • Several research classification systems exist. Most share several of the history and physical findings listed below.
PHYSICAL EXAM
  • Facial symmetry, muscle hypertrophy, intraoral exam
  • Palpation of muscles of mastication may reproduce pain.
  • Test jaw range of motion (opening, closing, lateral, protrusive) and masticatory muscle strength.
    • Maximal (pain-free) jaw opening with interincisal distance < 40 mm is suggestive of joint rather than muscle pathology if accompanied by other signs and symptoms (normal 35 to 55 mm).
    • Deviation to the affected side is common.
  • Muscle tenderness and restricted pain-free opening are most consistent distinguishing signs.
  • There may be tenderness over the TMJ.
  • Clicking or crepitus of jaw with opening
DIFFERENTIAL DIAGNOSIS
  • Condylar fracture/dislocation
  • Trigeminal neuralgia
  • Dental or periodontal conditions
  • Neoplasm of the jaw, orofacial muscles, or salivary glands
  • Acute, nondental infection: parotitis, sialadenitis, otitis, mastoiditis
  • Jaw claudication: giant cell arteritis
  • Migraine or tension type headache
  • Ramsay-Hunt syndrome (zoster auricular syndrome)
DIAGNOSTIC TESTS & INTERPRETATION
  • There are no labs to rule in TMD.
  • Blood work may be useful to rule out other conditions (CBC, CMP, ESR, CRP).
Initial Tests (lab, imaging)
  • TMD is a clinical diagnosis based primarily on history and physical exam.
  • Often, a poor correlation is found between pain severity and pathologic changes seen in joint or muscle tissues. Consider the following for severe or treatment-resistant cases, with MR or CT more useful as part of surgical workup:
    • Panoramic dental radiographs are a good first-line screen.
    • CT scan allows fine detail of bony structures, preferred for trauma.
    • US: Effusion and findings correlate with MRI and subjective pain.
    • MRI: noninvasive study for disc position; more sensitive than US; can help determine need for surgical management
Diagnostic Procedures/Other
  • Local anesthetic nerve block can differentiate orofacial pain of articular versus muscular origins.
  • Arthroscopy can be diagnostic for cartilage and bony pathology.
Test Interpretation
Positive findings include:
  • Condylar head displacement
  • Anterior disc displacement
  • Posterior capsulitis
  • Loosening of disc and capsular attachments
  • Chondroid metaplasia of disc leading to disc perforation and degeneration
image TREATMENT
Signs and symptoms will abate without intervention in most patients. 50% report improvement in 1 year and 85% by 3 years. With conservative therapy, symptoms resolve in 75% of cases within 3 months.
  • Therapeutic exercises, especially if displacement is present, including formal physical therapy.
  • Psychosocial interventions, including cognitivebehavioral therapy with or without biofeedback (2)[A]
  • Behavior modification to eliminate tension-relieving oral habits (2)[A]
  • Occlusal adjustment cannot be recommended for the management or prevention of TMD, as there is an absence of evidence from RCTs that occlusal adjustment treats or prevents TMD (3)[A].
  • Insufficient evidence exists either for or against the use of stabilization splint therapy for the treatment of TMD (4)[A].
  • P.1019

  • The American Dental Association recommends a “less is often best” stepwise approach and offers the following stepwise progression for therapy:
    • Eating softer foods
    • Avoiding chewing gum and nail biting
    • Modifying pain with heat or ice
    • Relaxation techniques including meditation and biofeedback
    • Exercises to strengthen jaw muscles
    • Medications
    • Night guards and orthotics
MEDICATION
First Line
  • Acetominophen
  • Naproxen
  • Topical methylsalicylate
  • Gabapentin
  • Ibuprofen, if osteoarthritis is suspected (5)[B].
Second Line
  • Muscle relaxants
  • Tricyclic antidepressants, SSRIs, or SNRIs
  • Botulinum neurotoxin
  • Acupuncture
  • Opiates should be reserved for perioperative or severe or recalcitrant cases (5)[B].
  • Ineffective medications (5)[B]
    • The following medications when compared with placebo in RCTs were shown to be ineffective in improving pain and should not be used for the treatment of TMD:
      • Benzodiazepines
      • Topical capsaicin
      • Diclofenac
      • Celecoxib
ADDITIONAL THERAPIES
Joint and muscle injections
  • There is very limited evidence to recommend for or against injections into or around the TMJ. Proposed therapies include steroids, hyaluronic acid, local anesthetics, and, recently, botulinum toxin.
  • Steroids given >3 times annually may accelerate degenerative changes.
  • Injections into inferior space or double spaces have better effect than superior space injections alone.
  • Recent studies suggest that botulinum toxin type A (Botox) injections may be successful in cases that have failed first-line pharmacologic therapy (6)[B].
COMPLEMENTARY & ALTERNATIVE MEDICINE
  • Glucosamine may be effective if pain is secondary to osteoarthritis of the TMJ (5)[B].
  • Multiple electronic diagnostic and treatment modalities are currently marketed to patients; however, the scientific literature does not support the use of electronic diagnostic and treatment devices for TMD at this time.
image ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
  • Relax jaw by disengaging teeth.
  • Avoid wide, uncontrolled opening, such as yawning.
  • Stress management and behavior-modification counseling may be helpful.
  • Be aware of any teeth-clenching or grinding habits.
Patient Monitoring
  • Ongoing assessment of clinical response to conservative therapies (NSAIDs, behavior modification, occlusal splints) is necessary.
  • Surgical procedure (arthroplasty, joint replacement) to correct disc displacement or replace a damaged disc may be indicated only if the patient has not responded to conservative treatment.
DIET
Soft diet to reduce chewing
PROGNOSIS
  • With conservative therapy, symptoms resolve in 75% of cases within 3 months.
  • Patients benefit most from a comprehensive treatment approach including the following:
    • Restoration of normal muscle function
    • Pain control
    • Stress management
    • Behavior modification
REFERENCES
1. Slade GD, Fillingim RB, Sanders AE, et al. Summary of findings from the OPPERA prospective cohort study of incidence of first-onset temporomandibular disorder: implications and future directions. J Pain. 2013;14(12)(Suppl):T116-T124.
2. Aggarwal VR, Lovell K, Peters S, et al. Psychosocial interventions for the management of chronic orofacial pain. Cochrane Database Syst Rev. 2011;(11):CD008456.
3. Koh H, Robinson PG. Occlusal adjustment for treating and preventing temporomandibular joint disorders. Cochrane Database Syst Rev. 2003;(1):CD003812.
4. Al-Ani MZ, Davies SJ, Gray RJ, et al. Stabilisation splint therapy for temporomandibular pain dysfunction syndrome. Cochrane Database Syst Rev. 2004;(1):CD002778.
5. Mujakperuo HR, Watson M, Morrison R, et al. Pharmacological interventions for pain in patients with temporomandibular disorders. Cochrane Database Syst Rev. 2010;(10):CD004715.
6. Ihde SK, Konstantinovic VS. The therapeutic use of botulinum toxin in cervical and maxillofacial conditions: an evidence-based review. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007;104(2):e1-e11.
Additional Reading
&NA;
  • American Dental Association. Patient Information. http://www.ada.org/en/Home-MouthHealthy/az-topics/t/tmj.
  • De Rossi SS, Greenberg MS, Liu F, et al. Temporomandibular disorders: evaluation and management. Med Clin North Am. 2014;98(6):1353-1384.
  • Scrivani SJ, Keith DA, Kaban LB. Temporomandibular disorders. N Engl J Med. 2008;359(25):2693-2705.
See Also
&NA;
  • Headache, Tension
  • Temporomandibular Joint (TMJ) Disorder
Codes
&NA;
ICD10
  • M26.60 Temporomandibular joint disorder, unspecified
  • M26.62 Arthralgia of temporomandibular joint
  • M26.63 Articular disc disorder of temporomandibular joint
Clinical Pearls
&NA;
  • The condition called TMD actually designates a number of potential underlying joint and muscle conditions involving the jaw.
  • Characteristics of all are pain and functional limitation.
  • TMD is a clinical diagnosis with limited utility of imaging.
  • Cognitive-behavioral therapy reduces pain, depression, and limitation of function.
  • Exercises may improve function and pain.
  • Evidence is lacking to support occlusion correction or splinting.
  • Naproxen, gabapentin, topical methylsalicylate, glucosamine, amitriptyline, acupuncture, and botulinum toxin injections have some evidence of efficacy.