H&N, OCSE, TMJ Flashcards
How do you evaluate the clinical joint surfacs of the TMJ?
1) active protrusion followed by opening - fist with fingers over condyle, then a dynamic compression test with fingers under angle of mandible
2) if dynamic compression provokes crepitus, continue with dynamic translations
Bumann & Lotzmann - TMJ Disorders and Orofacial Pain (textbook)
What does crepitus in the TMJ indicate?
osteoarthrotic changes in the functional joint surfaces
1) crepitus during protrusion – osteoarthrotic changes in the temporal joint surface
2) crepitus during opening – changes in the condylar surface
crepitus with pain = arthritis
crepitus without pain = arthrosis
Bumann & Lotzmann - TMJ Disorders and Orofacial Pain (textbook)
What does clicking in the TMJ indicate?
most commonly disk displacement (usually anteromedial)
causes:
- disk hypermobility
- partial or total disk displacement
- disk displacement with adhesion
- disk displacement with terminal repositioning
- lateral ligament impingement
- hypertrophic cartilage
- condyle hypermobility
Bumann & Lotzmann - TMJ Disorders and Orofacial Pain (textbook)
What is the cause of a TMJ click at the end of active protrusion or jaw opening?
condyle hypermobility or
disk displacement with terminal repositioning
Bumann & Lotzmann - TMJ Disorders and Orofacial Pain (textbook)
What is the average maximum force one can generate on their anterior teeth?
140-200N (about 1/3 of the posterior bite force)
What is the average maximum force one can generate on their posterior teeth?
600-750N (about 3x the anterior bite force)
Hagberg
In which compartment of the TMJ (upper or lower) does the initial 20mm of rotation/opening compared to the remainder of opening?
lower - initial 20mm (rotation)
upper - remainder (translation)
Average maximum jaw opening (range in mm)
49-56mm
Average protrusion and laterotrusion (range in mm)
10-11mm
What is the endfeel of a healthy TMJ?
What is indicated if the endfeel is too soft or too hard?
hard ligamentary: healthy
soft: muscle contracture
too hard: capsule shrinkage
rebounding: nonreducing disk displacement
bony: hyperplasia of the coronoid process or ankylosis
What is the difference between a relaxation splint and a stabilization splint?
relaxation: normalize muscle tone by distributing forces equally (in CR)
stabilization: secure the max-mand relationship established by therapy and test the results of therapy for 4-6 weeks; occlusal indentations are deeper than relaxation splint
What is a decompression splint?
design is like relaxation splint with ant guidance
purpose: Tx compromised TMJ in which constriction of capsule, muscles, and ligaments interferes with relief of articular structures that would be provided by occlusion
How can you determine whether a patient’s pain is due to capsular derangement?
1) guiding the patient into CR causes pain
2) clenching on a separator unilaterally relieves pain on that side due to decrease in interarticular pressure on that side
Okeson
Actions of the masseter
closes
stabilizes condyle during protrusion (lesser)
Actions of the temporalis
closes
retrudes
other: coordinates mandibular movements (due to multidirectional fibers)
Actions of the medial pterygoid
closes
protrudes
mediotrudes
Actions of the inferior lateral pterygoid
protrudes
mediotrudes
opens (lesser)
Actions of the superior lateral pterygoid
closes (power stroke)
What muscles are attached to the TMJ?
masseter
temporalis
medial pterygoid
inferior & superior lateral pterygoid
Aside from the major muscles of mastication, what other muscles help stabilize and coordinate jaw movements?
digastric, mylohyoid, geniohyoid
Patient has pain on protrusion with resistance. What muscle is likely affected?
**inferior lateral pterygoid
**
Pain would also increase when pt clenches on teeth (ILP stretches) but not when pt clenches on a separator.
Patient has pain when clenching on teeth and when clenching on a separator. No pain on opening. What muscle is likely affected?
superior lateral pterygoid
Patient has pain when clenching on teeth, when clenching on a separator, and when opening. What muscle is likely involved?
medial lateral pterygoid
Patient has pain during protrusion with resistance, clenching on teeth, and jaw opening. However, clenching on a separator relieves pain on the opposite side. What is the likely cause?
capsular derangement
