At present, there is no widely accepted, standard diagnostic test to identify all TMJ disorders. Because the exact causes and symptoms are not clear, identifying these disorders can be difficult and confusing. The American Association for Dental Research recommends that a diagnosis of TM disorders or related orofacial pain conditions should be based primarily on information obtained from the patient’s history and a clinical examination of the head and neck.

In addition to a detailed history and a careful clinical examination, imaging studies of the teeth and jaws may sometimes be helpful as a diagnostic tool. These include:

• Routine Dental X-rays and Panoramic Radiographs. These show the teeth and provide a screening view of the bony structures of the TM joint.
• Computed Tomography (CT or CAT scan). This provides greater detail of the bone but a somewhat limited view of the disc and soft tissues. It is indicated when a screening radiograph of the TM joint shows some bony changes.
• Magnetic Resonance Imaging (MRI). This provides images of the disc as well as the muscles and other soft tissues surrounding the joint.
• Scintigraphy (Bone scan). This involves the injection of a radioactive substance that is absorbed by the bone cells and shows whether a pathologic process is in an active or inactive state.

Blood tests are sometimes recommended to rule out possible medical conditions as a cause of the problem.

Before undergoing any costly diagnostic test, it is always wise to get an independent opinion from another health care provider of your choice who is not associated with your current provider.

Articles of Interest:

• Diagnostic accuracy of clinical tests and signs of TMJ disorders: A Systematic review of the literature.

• Technological devices in the diagnosis of temporomandibular disorders

• What you can and cannot see in TMJ imaging – an overview related to the RDC/TMD diagnostic system

• American Association for Dental Research Temporomandibular Disorders Policy Statement - March 2010

• Do computed tomography and magnetic resonance imaging add to temporomandibular joint disorder treatment? A systematic review of diagnostic efficacy

• Electromyography in diagnosing temporomandibular disorders

  The authors of this systematic review found no evidence to support the use of EMG for the diagnosis of TMD.

Conditions Which May Produce Similar Signs and Symptoms as TMJ Disorders

Conditions that may produce similar signs and symptoms as TMJ Disorders (pain and/or jaw dysfunction) and can lead to misdiagnosis include:

• Atypical (vascular) neuralgia

• Hypo- and hyperkinesia (abnormal jaw movements)

• Lyme disease

• Myositis (muscle inflammation)

• Myositis ossificans (calcification in a muscle)

• Otitis (earache)

• Parotitis (salivary gland inflammation)

• Scleroderma (chronic hardening of the skin)

• Sinusitis

• Temporal arteritis (inflammation of the temporal artery)

• Toothache

• Trigeminal neuralgia

• Trotter's syndrome (nasopharyngeal carcinoma)