Definitions and Terminology, Prevalence and Demographics - TMD is an umbrella term covering pain and dysfunction of the muscles of mastication and the temporomandibular joints. - TMD is not life-threatening but can be detrimental to quality of life. - The term TMD is taken to mean any disorder that affects the temporomandibular joint. - There is no single, globally accepted term or definition for TMD. - TMD often co-occurs with other medical conditions such as headaches, fibromyalgia, back pain, and irritable bowel. - About 20% to 30% of the adult population are affected by TMD to some degree. - TMD is more common in females than males. - TMD is the second most frequent cause of orofacial pain after dental pain. - TMD is considered one of the 4 major symptom complexes in chronic orofacial pain. - TMD is considered a musculoskeletal, neuromuscular, or rheumatological disorder.

Causes and Symptoms - TMD may develop following physical trauma, such as whiplash injury. - Muscle-related TMD and joint-related TMD are two classifications of TMD. - The Research Diagnostic Criteria (RDC/TMD) allows for multiple diagnoses. - TMD can be acute (symptoms last less than 3 months) or chronic (symptoms last more than 3 months). - Symptoms of TMD can involve various components of the masticatory system. - Pain aggravated by manipulation or function (chewing, clenching, yawning) - Dull or aching pain, poorly localised and intermittent - Unilateral pain (one side) rather than bilateral - Limited range of mandibular movement, causing difficulty eating or talking - Noises from the joint during movement (clicking, popping, crepitus)

Treatment Options - There are many treatments available for TMD, but there is a lack of evidence for their effectiveness. - Common treatments include occlusal splints, cognitive behavioral therapy, physical therapy, and pain medication. - Irreversible treatments should not be carried out for TMD. - There is no widely accepted treatment protocol for TMD. - Treatment for TMD should be individualised based on the patient's specific symptoms and needs.

Complications and Controversies - TMD can lead to chronic and difficult-to-manage symptoms. - The causes and factors associated with TMD are poorly understood. - There is disagreement about the relative importance of overlapping medical conditions in TMD. - The terminology and classification of TMD are still debated. - TMD has been compared to other pain syndromes like fibromyalgia and chronic lower back pain.

Subtopics (Symptoms, Causes, Mechanisms, Joint Noises, Pain Symptoms, Degenerative Joint Disease, Diagnosis) - Subtopic 1: Symptoms - Subtopic 2: Causes (Trauma, Occlusal factors, Genetic factors, Hormonal factors, Possible associations) - Subtopic 3: Mechanisms of TMJ movement - Subtopic 4: Joint noises - Subtopic 5: Pain symptoms - Subtopic 6: Degenerative joint disease - Subtopic 7: Diagnosis (RDC/TMD criteria)