TMD Flashcards
How is pain defined according to the TMD lecture?
Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. It is influenced by biological, psychological, and social factors.
What are the four categories of orofacial pain?
- Musculoskeletal Pain (Myalgia, Arthralgia)
- Neuropathic Pain (Neuralgia, Neuropathy, Orofacial movement disorders)
- Neurovascular Pain (Migraines, Trigeminal Autonomic Cephalgias)
- Pain of Nonorganic Etiologies (Somatic Symptom Disorder)
What type of joint is the temporomandibular joint (TMJ), and what are its movements?
The TMJ is a ginglymoarthrodial joint, meaning it has both hinging (rotation) and gliding (translation) movements.
What is the composition of the TMJ articular disc, and why is it significant?
The articular disc is made of dense fibrous tissue, mostly devoid of blood vessels and innervation, which allows smooth joint movement.
What nerve provides primary innervation to the TMJ, and what arteries supply it?
The auriculotemporal nerve (a branch of the mandibular division of the trigeminal nerve) provides innervation. Blood supply comes from the superficial temporal artery, internal maxillary artery, and middle meningeal artery.
Name the muscles of mastication and their primary functions.
• Masseter: Elevates mandible
• Temporalis: Elevates and retrudes mandible
• Medial Pterygoid: Elevates and protrudes mandible
• Lateral Pterygoid: Assists with mandibular movements (protrusion, depression, lateral deviation)
What is the prevalence of TMD symptoms, and who is most affected?
TMD symptoms are more prevalent in women (2:1 ratio to men), with peak occurrence between ages 20–40. About 13% experience masticatory muscle pain, and 16% have disc derangement disorders.
What are common etiological factors for TMD?
• Acute trauma (e.g., whiplash, hyperextension from dental procedures)
• Parafunctional habits (bruxism, clenching)
• Psychological factors (stress, anxiety, depression)
• Systemic conditions (RA, fibromyalgia, joint hypermobility)
What role does occlusion play in TMD?
Although previously thought to be a primary cause, current evidence suggests occlusion has limited influence on TMD. Certain occlusal factors (large overjet, open bite, unilateral crossbite) are more common in TMD patients but may not be causative.
What are the classifications of pain duration in TMD?
- Intermittent – Pain comes and goes with pain-free intervals
- Continuous/Persistent – No pain-free intervals
- Recurrent – Episodes separated by extended periods of relief
What types of joint sounds are associated with TMD?
• Clicking: Often linked to disc displacement with reduction
• Crepitus (grating sound): Commonly associated with osteoarthritis
Differentiate between disc displacement with and without reduction.
• With reduction: Disc is displaced anteriorly but returns to position upon opening (clicking sound).
• Without reduction: Disc remains displaced, causing limited mouth opening (<40mm) and pain.
What are the key features of TMJ osteoarthritis?
• Degeneration of joint surfaces
• Crepitus on palpation
• May cause anterior open bite (bilateral cases)
• Radiographic evidence of condylar flattening, osteophytes
What are the primary conservative treatments for TMD?
• Behavioral modifications (avoid clenching, chewing gum)
• Physical therapy (jaw exercises, posture correction)
• Home care (warm compresses, soft diet)
• Pharmacotherapy (NSAIDs, muscle relaxants)
• Occlusal splints (stabilization appliances)
What invasive treatments are available for severe TMD cases?
• Arthrocentesis / Arthroscopy (minimally invasive joint flushing)
• Arthroplasty (surgical disc repositioning or joint reconstruction)
• Total Joint Replacement (for severe degenerative cases)
