Lecture 24: Infratemporal Fossa

Question 1

Slicing: mastication

Answer 1

sharp edges coming together or shearing past each other
Eating meat

Question 2

Grinding: mastication

Answer 2

Sliding of rough or textured surfaces
Circular, side to side movements

Question 3

Temporomandibular joint

Answer 3

formed by the condyle (head) of the mandible
and the mandibular (glenoid) fossa of the temporal bone

Question 4

Functions of lateral ligament in TMJ (2)

Answer 4

Prevent lateral displacement of condyle
Prevent excessive Rostral displacement when mouth is open

Question 5

Movement prevented by retroarticular process in TMJ

Answer 5

Prevent posterior/caudal displacement

Question 6

Movement prevented by joint capsule, surrounding muscles and proper use of mandible: TMJ

Answer 6

Ventral displacement (so condyle doesn’t pop out)

Question 7

Are anterior/Rostral movements at TMJ restricted

Answer 7

No

Question 8

2 types of lateral excursions of mandible

Answer 8

Ipsilateral
Contralateral

Question 9

Ipsilateral excursion (chewing) of mandible

Answer 9

lateral movement of anterior mandible and tooth due to muscles that move on the same side (i.e. lateral pterygoid and medial pterygoid)

Question 10

Contralateral excursion of mandible

Answer 10

Anterior mandible and tooth row move opposite side from muscle

Question 11

How are lateral movements of anterior mandible and tooth row produced

Answer 11

Retractors of same side = Ipsilateral
Protruders of opposite side = Contralateral

Question 12

4 muscles of mastication

Answer 12

Temporalis
Masseter
Medial pterygoid
Lateral pterygoid

Question 13

Muscles of mastication all cross ______ and are innervated by what nerve

Answer 13

TMJ
V3/mandibular nerve

Question 14

Temporalis: OINA (2 actions)

Answer 14

O - temporal fossa
I - coronoid process
N - V3
A - bilateral jaw closing
Unilateral: some retraction of mandible

Question 15

Masseter: OINA (2 actions)

Answer 15

O - zygomatic arch
I - Masseteric fossa and angular process of mandible
N - V3
A - bilateral jaw closing
Unilateral - superficial fibers protract mandible, deep fibers retract mandible

Question 16

Medial pterygoid: OINA

Answer 16

O - pterygopalatine fossa
I - medial surface of mandibular ramus and angular process
N - V3
A - bilateral jaw closing
Unilateral - protraction

Question 17

Lateral pterygoid: OINA

Answer 17

O - pterygopalatine fossa
I - Capsule of TMJ and articular disk
N - V3
A - control position of articular disk during jaw movement

Question 18

Primary mastication functions of carnivores and Omnivores

Answer 18

Slicing and crushing

Question 19

Largest jaw closer muscle in carnivores

Answer 19

Temporalis

Question 20

Which muscles predominate in herbivores

Answer 20

Masseter and medial pterygoid

Question 21

Zygomatic arch: carnivores vs herbivores

Answer 21

Carnivores = wide
Herbivores = less prominent

Question 22

TMJ: herbivores vs carnivores

Answer 22

Carnivores = more hinge like joint to restrict unilateral protraction and retraction
Herbivores = flatter, less restricted to unilateral protraction and retraction

Question 23

Mylohyoid: OINA

Answer 23

O - medial aspect of mandibular body
I - midline rap he with fibers from opposite muscle and basihyoid (muscular hammock)
N - mylohyoid nerve from V3
A - raise floor of oral cavity to support tongue and draw basihyoid Rostrally

Question 24

Digastric: unique feature

Answer 24

Digastric = 2 bellies
Split muscle with caudal and Rostral bellies separated by tendon

Question 25

Digastric: OIN(2)A

Answer 25

O - paracondylar process I - ventral and medial aspect of mandible N - Rostral: mylohyoid nerve from V3 Caudal: facial nerve A - active depression of mandible to open jaw

Question 26

Unique innervation in Digastric (2)

Answer 26

Rostral = mylohyoid nerve Caudal = facial nerve

Question 27

Occipitomandibularis: definition, species

Answer 27

Accessory belly of caudal Digastric found in horses

Question 28

Mandibular nerve: types of innervation

Answer 28

Motor - muscles of mastication Sensory - skin and mucosa of mandibular region (ear, cheek, jawline, lower lip, tongue, mandibular teeth)

Question 29

Sensory branches of mandibular nerve (5)

Answer 29

Buccal Auriculotemporal Inferior alveolar Mylohyoid Lingual

Question 30

Buccal nerve: branch of mandibular

Answer 30

From skin of cheek and underlying oral mucosa

Question 31

Auriculotemporal nerve: mandibular

Answer 31

Stuck underneath parotid tissue Parts of external ear Most of skin over Temporalis, masseter, zygomatic arch

Question 32

Inferior alveolar nerve: mandibular

Answer 32

Enters mandibular foramen Mandibular teeth

Question 33

Mental nerve is branch of what nerve

Answer 33

Inferior alveolar

Question 34

Mental nerve: mandibular branch

Answer 34

Branch of inferior alveolar Exits mental foramen From skin of chin

Question 35

Mylohyoid nerve: mandibular nerve

Answer 35

Mostly motor to mylohyoid and Rostral Digastric muscles Sensory to skin below mandibular body

Question 36

Lingual nerve: mandibular

Answer 36

Parallel to inferior alveolar nerve Sensory from anterior 2/3 of tongue and lingual mucosa Special sensory and preganglionics from facial nerve

Question 37

3 parts of maxillary artery

Answer 37

Mandibular Pterygoid Pterygopalatine

Question 38

Inferior alveolar artery runs with what nerve

Answer 38

Inferior alveolar

Question 39

Which nerve and artery art part of the mandibular portion of maxillary artery

Answer 39

Inferior alveolar Middle meningela

Question 40

Artery and nerve that’s part of pterygopalatine portion of maxillary

Answer 40

Buccal artery and buccal nerve from V3