Neuro Exam 1 TMJ and Joints

Question 1

Synathrosis

Answer 1

An immovable joint like a suture, or gomphosis (b/w roots of teeth and alveolar process)

Question 2

Amphiarthrosis

Answer 2

slightly movable joint, includes fibrocartillage between veterbrae (allows movement) and pubic symphysis (allows baby passage)

Question 3

Diarthrosis

Answer 3

synovial-freely movable; lined by a synovial membrane which produces synovial fluid, includes typical and w/ articular disc

Question 4

typical diarthrotic joint

Answer 4

the ends of two bones are covered by articular cartilage, ligaments join the bones together, capsular ligaments, and joint cavity (lined by synovial membrane)

Question 5

Diarthrotic joint w/ articular disc

Answer 5

a synovial joint where everything is the same except there is an articulating disc seperating the two

Question 6

Arthroidal joint

Answer 6

plane or gliding (acromioclavicular-clavicle and scapula)

Question 7

Ginglymus joint

Answer 7

Hing; motion in one plane (elbow)

Question 8

Trochoid joint

Answer 8

Pivot; rotation around one axis (i.e. dens and atlas joint-allows turning of head)

Question 9

Condyloid joint

Answer 9

motion in two planes, no rotation (i.e. condyles of head on spine allows rocking side to side and front to back)

Question 10

enarthroidal (ball and socket)

Answer 10

motion in all planes, plus rotation (i.e. hip joint)

Question 11

Sellar (saddle or ellipsoid)

Answer 11

motion in two planes, some axial rotation (i.e. joint in thumb between first carpal and metacarpal)

Question 12

TMJ Bones and covering

Answer 12

mandibular fossa of temporal bone, and head of mandibular condyle; articular surfaces covered by fibrous tissue

Question 13

Classification of TMJ joint

Answer 13

Ginglymoarthroidal (hinge and gliding combination), bilateral (b/c on both sides of the jaw), and a synovial joint with an articular disc

Question 14

Articular eminence

Answer 14

next to/bottom of mandibular fossa; roof or fossa is thin and may not bear pressure

Question 15

Capsule (capsular ligament)

Answer 15

dense fibrous CT running from zygomatic arch to mandible; makes sure head stays in place

Question 16

Makes sure the head of the condylar process remains in the mandibular fossa

Answer 16

capsule/capsular ligament

Question 17

Articular Disc (meniscus)

Answer 17

made of dense fibrous tissue which divides the interior joint into sup. (gliding) and inf. compartments (hinge motion); peripheri is thicker and attaches to capsule

Question 18

motion of the inf compartment of articular disc

Answer 18

hinge motion

Question 19

motion of sup. compartment of articular disc

Answer 19

gliding motion

Question 20

Composition of central region of articular disc

Answer 20

more fibrocartilage; more rigid

Question 21

retrodiscal ligament composition (of articular disc)

Answer 21

more elastic fibers; more flexible

Question 22

Temporomandibular (lateral) ligament

Answer 22

covers the capsular ligament; runs from zygomatic process of temporal bone to neck of mandibular condyle; prevents posterior displacement and excess lateral displacement of condyle

Question 23

Sphenomandibular joint

Answer 23

runs from the spine of the sphenoid to the lingula of the mandible; becomes taught during excessive opening

Question 24

becomes taut during excessive opening

Answer 24

sphenomandibular

Question 25

prevents post. displacement and excess lateral displacement of condyle

Answer 25

temporomandibular ligament (lateral)

Question 26

Stylomandibular ligament

Answer 26

runs from styloid process of temporal to the angle of the mandible; becomes taut in excessive protrusion

Question 27

taut in protrusion

Answer 27

stylomandibular ligament

Question 28

Nerve innervation of the TMJ

Answer 28

mandibular branch of the trigeminal (V3 of CN5); auriculotemporal (most branches), masseteric (branches to small ant. portion), deep temporal (branches to small ant. portion)

Question 29

gives of branches to most of the joint

Answer 29

auriculotemporal

Question 30

innervates the small ant. portion of the TMJ

Answer 30

the masseteric and deep temporal parts of the mandibular branch (V3) of the trigeminal (CN5)

Question 31

Proprioceptive

Answer 31

sense of space (jaw open to long)

Question 32

Pain Receptors

Answer 32

free nerve endings (overextension)

Question 33

Blood Supply to TMJ

Answer 33

Superficial temporal art (post capsule) which is terminal branch of ext. carotid art. and maxillary artery (deeper into mandibular space) which is a terminal branch of ext. carotid artery

Question 34

Where blood supply of TMJ branches from

Answer 34

External carotid artery

Question 35

supplies post. capsule of TMJ

Answer 35

superficial temporal artery

Question 36

Supplies the deep portion into the mandibular space of TMJ with blood

Answer 36

Maxillary artery

Question 37

Motion of TMJ

Answer 37

combination of hinge and gliding

Question 38

Protrusion

Answer 38

condyles move forward; discs glide down articular eminence

Question 39

Retrusion

Answer 39

condyles move back, discs glide up the eminence

Question 40

Depression

Answer 40

condyles rotate anteriorly around a horizontal axis, articular disc glides down,the articular eminence; when opening wide both protrusion and depression happen

Question 41

condyles rotate anteriorly around a horizontal axis, articular disc glides down,the articular eminence

Answer 41

depression

Question 42

elevation

Answer 42

discs glide back up the articular eminence and the condyles rotate posteriorly around a horizontal axis

Question 43

lateral deviation to right

Answer 43

aka excursions; to the right --> disc on left slides down eminence and the right condyle rotates slightly anteriorly

Question 44

lateral deviation to left

Answer 44

disc on right side slides down eminence and the left condyle rotates slightly anteriorly

Question 45

muscles for protrusion

Answer 45

lateral pterygoids

Question 46

muscle for retrusion

Answer 46

post/horizontal fibers of temporalis, deep fibers of massetter

Question 47

depression

Answer 47

suprahyoids, infrahyoids, and lateral pterygoids in wide opening (involves protrusion)

Question 48

elevation

Answer 48

massetter, temporalis, medial pterygoid

Question 49

lateral deviation

Answer 49

opposite lateral pterygoid

Question 50

disorders of function (and how common)

Answer 50

fractures of the mandible: -30% at neck, at neck of condyle -25% at angle -22% at chin Subluxation (partial dislocation) and dislocation -head of mandibular condyle is ahead of the articular tubercle