Flashcards in Temporomandibular Joint Deck (43)
muscle activation + joint motion =
How is the position of the TMJ joint maintained?
position maintained by: muscles, ligaments, and the TM joint capsule
M-L length is __x that of the A-P
Where is the TMJ palpated?
Palpated at the lateral pole just anterior to the external auditory meatus
What are the 2 joint surfaces covered by?
The articular surface are both ________ ( -->incongrutent joint)
What is the articular disc interposed between?
the joint surfaces
The inferior TM joint cavity is made up of the:
mandibular condyle and inferior surface of the disc
The inferior TM joint cavity is considered a _______ joint.
The superior TM joint cavity is made up of the:
articular eminence and superior surface of the disc
The superior TM joint cavity is considered a _____ joint.
What are three properties of the articular disc?
1) bi-concave fibrocartilage disc
2) avascular and insensate
3) thin in the central portion and thickens anterior and posterior
Name 5 functions of the articular disc:
1) congruency for joint articulations
3) minimizes loss of mobility
4) reduces friction
5) decreases stress on the TMJ
Is the lateral ligament of the TMJ complex the primary or secondary ligament?
What function does the lateral ligament serve?
stabilizes the lateral aspect of the capsule
guides the condylar movement during mouth opening
What is normal ROM for depression and elevation
What is normal ROM for lateral deviation?
What is normal ROM for protrusion
What is normal ROM for retrusion
What muscles aid in depression?
suprahyoids and lateral pterygoind (inferior head)
What muscles aid in elevation?
temporalis, masseter, medial pterygoid
What muscles aid in lateral deviation?
medial & lateral pterygoid to opposite side (contralateral movement) and temporalis to same side (ipsilateral)
What muscles aid in retrusion?
bilateral temporalis and suprahyoids
What is the depression/ opening of the mouth responsible for?
key for may functional activities
What is the elevation/ closing of the mouth responsible for?
essential for grinding food
What is the lateral deviation of the mouth responsible for?
-side to side translation
-grinding motion associated with chewing
What is the protrusion of the mouth responsible for?
(Mandible translates anteriorly)
Integral aspect of maximal opening of mouth
What is the retrusion of the mouth responsible for?
(madible translates posteriorly)
Essential for functional activities
The first 11* of arthrokinematic motion of the TMJ includes ______?
The condyle rolls relative to the inferior surface of the disc in the inferior joint