Articulator/Muscles of Face

Question 1

What is an articulator?

Answer 1

A mechanical device that simulates mandibular movements of condyles in their fossae

Question 2

What are the parts of functional anatomy?

Answer 2

• dentition and supportive structures
• skeletal components
• temporomandiular joints
• ligaments
• muscles

Question 3

What are the parts of the skeleton (face)?

Answer 3

maxillar
mandibule
temporal bone

Question 4

What are the features of the maxilla?

Answer 4

• 2 maxillary bones (fused at mid-palatal suture)

Question 5

What is the superior border of the maxilla?

Answer 5

floor of the nasal cavity and orbit

Question 6

What is the inferior border of the maxilla?

Answer 6

palate and alveolar ridge

Question 7

What are the components fo the maxilla?

Answer 7

• body
• processes (zygomatic, frontal, alveolar, palatine)

Question 8

What is the largest and strongest bone on the skull?

Answer 8

mandible

Question 9

What are the components of the mandible?

Answer 9

body
ramus

Question 10

What are the parts of the body of the mandible?

Answer 10

mandibular angle
ascending ramus
- coronoid process
- condyle

Question 11

Where does the condyle of the mandible articulate?

Answer 11

the cranium

Question 12

What is the mediolateral length of the condyle of mandible?

Answer 12

15-20 mm

Question 12

What is the anterior-posterior width of the condyle mandible?

Answer 12

8-10 mm

Question 13

What does the squamous portion of the temporal bone articulate with?

Answer 13

mandibular condyle

Question 14

What is the articular eminence?

Answer 14

thick dense bone to tolerate heavy forces

Question 15

What are the four main muscles of mastication?

Answer 15

lateral pterygoids
medial pterygoid
masseter
temporalis

Question 16

What are the two heads of the masseter?

Answer 16

superficial (fibers run down and back)
deep (fibers run vertical)

Question 17

What is the origin of the masseter?

Answer 17

zygomatic arch

Question 18

What are the insertions of the masseter?

Answer 18

lateral surface of ramus
angle of the mandible

Question 19

What is the function of the masseter?

Answer 19

• elevates the mandible
• provides the force for chewing

Question 20

What is the function of the superficial head of the masseter?

Answer 20

aids in protrusion

Question 21

What is the function of the deep head of masseter?

Answer 21

stabilizes the condyle against the eminence

Question 22

What is the blood supply to the masseter?

Answer 22

muscular branch of the maxillary artery

Question 23

What is the nerve supply to the masseter?

Answer 23

masseteric nerve of mandibular division of trigeminal nerve

Question 24

What are the three distinct divisions of the temporalis?

Answer 24

anterior (vertical fibers) middle (oblique fibers) posterior (horizontal fibers)

Question 25

What is the origin for the temporalis?

Answer 25

temporal fossa and lateral surface of the skull

Question 26

What is the insertion of the temporalis?

Answer 26

coronoid process anterior border of ascending ramus

Question 27

What is the action of the anterior temporalis?

Answer 27

mandible is raised vertically

Question 28

What is the action of the middle temporalis?

Answer 28

elevates and retrudes the mandible

Question 29

What is the action of the posterior temporalis?

Answer 29

aids in retrusion of the mandible

Question 30

What is the blood supply of temporalis?

Answer 30

a muscular branch of the maxillary artery

Question 31

What is the nerve supply of temporalis?

Answer 31

deep temporal nerve of the mandibular division of trigeminal nerve

Question 32

How many heads does the lateral (external) pterygoid have?

Answer 32

2 heads - superior lateral pterygoid - inferior lateral pterygoid

Question 33

What is the origin of the inferior layeral pterygoid?

Answer 33

outer surface of the lateral pterygoid plate

Question 34

What is the insertion of the inferior lateral pterygoid

Answer 34

neck of condyle

Question 35

What are the actions of the inferior lateral pterygoid?

Answer 35

bilateral contraction (mandible is protruded) unilateral contraction (mediotrusive movement)

Question 36

What is the superior lateral pterygoid origin?

Answer 36

infratemporal surface of the greater sphenoid wing

Question 37

What is the superior lateral pterygoid insertion?

Answer 37

disk, capsule, and neck of the condyle

Question 38

What is the action of the superior lateral pterygoid?

Answer 38

active with elevator muscles (closure of the mandible) - power stroke

Question 39

What is the blood supply for the lateral pterygoid?

Answer 39

muscular branch of the maxillary artery

Question 40

What is the nerve supply for the lateral pterygoid?

Answer 40

branch of the masseteric or buccal nerve of the mandibular division of the trigeminal nerve

Question 41

What is the origin of the medial (internal) pterygoid?

Answer 41

pterygoid fossa

Question 42

What is the insertion of the medial (internal) pterygoid?

Answer 42

medial surface of the mandibular angle

Question 43

What is the function of the medial (internal) pterygoid?

Answer 43

1. elevates the mandible 2. protrudes the mandible 3. unilateral contraction

Question 44

What is the blood supply to the medial (internal) pterygoid?

Answer 44

muscular branch of the maxillary artery

Question 45

What is the nerve supply of the medial (internal) pterygoid?

Answer 45

motor branch of the mandibular diviosn of the trigeminal nerve, which reaches the posterior border of the muscle near the base of the skull

Question 46

What are the two parts of the masseter sling?

Answer 46

masseter medial pterygoid

Question 47

What are the suprahyoid muscles?

Answer 47

geniohyoid mylohyoid digastric stylohyoid

Question 48

What are the functions of the suprahyoid muscles?

Answer 48

- elevate hyoid bone - depress the mandible when hyoid bone is fixed

Question 49

What is the origin of the geniohyoid?

Answer 49

inferior genial tubercle on the inner surface of mandibular symphysis

Question 50

What is the insertion of the geniohyoid?

Answer 50

anterior surface of body of hyoid bone

Question 51

What is the origin for the mylohyoid?

Answer 51

line from last molar root to mandibular symphysis

Question 52

What is the insertion of the mylohyoid?

Answer 52

median raphe from chin to hyoid bone

Question 53

What are the two bellies of the digastric muscle?

Answer 53

anterior posterior

Question 54

What are the two origins of the digastric muscle?

Answer 54

- posterior belly from the mastoid process - anterior belly from a depression on the inner side of the lower border of the mandible, close to the symphysis

Question 55

What is the insertion of the digastric muscle?

Answer 55

hyoid bone

Question 56

What muscles depress the mandible via contraction?

Answer 56

- inferior lateral pterygoids - digastric

Question 57

What muscles depress the mandible via relaxation?

Answer 57

- masseters - medial pterygoids - temporalis

Question 58

What muscles elevate the mandible via contraction?

Answer 58

- masseters - medial pterygoid - temporalis - superior lateral pterygoid

Question 59

What muscle elevates the mandible via relaxation?

Answer 59

- inferior lateral pterygoid - digastric

Question 60

What muscle provide right lateral movement via contraction?

Answer 60

- left inferior lateral pterygoid

Question 61

What muscles provide right lateral movement via relaxation?

Answer 61

- right inferior lateral pterygoid - slight relaxation of elevators

Question 62

What muscle provides left lateral movement via contraction?

Answer 62

- right inferior lateral pterygoid

Question 63

What muscles provide left lateral movement via relaxation?

Answer 63

- left inferior lateral pterygoid - slight relaxation of elevators

Question 64

What muscles allow for protrusion via contraction?

Answer 64

- inferior lateral pterygoids (mostly) - assisted by masseters and medial pterygoids

Question 65

What muscle allows for retrusion via contraction?

Answer 65

temporalis