Temporomandibular Disorders (TMDs) or TMJ Dysfunction
Temporomandibular disorders (TMDs) are a group of related musculoskeletal conditions affecting the masticatory muscles, the temporomandibular joint (TMJ), and associated structures. They are one of the most common causes of chronic orofacial pain. TMDs share clinical features, such as pain in the TMJ and surrounding structures, limitation of jaw movements, and/or sounds (such as clicking, popping, grating, or crepitus) from the TMJ.
TMDs have previously been referred to as TMJ disorders or TMJ dysfunction. The current term of TMDs is more clinically accurate as it encompasses disorders of associated structures as well as the TMJ itself.
Pain-related TMDs may be subdivided into different categories:
- Myalgia/myofascial pain — masticatory muscle disorders.
- Intra-articular disorders — such as disc displacement and/or arthralgia.
- Headache — typically confined to the temporal region.
TMDs may be also classified according to the duration of symptoms:
- Acute TMD pain is often of short duration, self-limiting, and may be related to prolonged jaw opening (such as following dental treatment or trauma).
- Chronic TMD pain is defined as lasting for more than 3 months.