Deep Face, Infratemporal Region, and TMJ

Question 1

Where is the temporal fossa located?

Answer 1

Superior to zygomatic arch

Question 2

Where is the infratemporal fossa located?

Answer 2

Inferior to zygomatic arch

Question 3

What are the boundaries of the infratemporal fossa (lateral, anterior, medial, roof, posterior, inferior)?

Answer 3

Lateral: ramus of mandible

Anterior: maxilla

Medial: lateral pterygoid plate

Roof: sphenoid (greater wing)

Posterior: tympanic plate, mastoid, and styloid processes

Inferior: angle of mandible

Question 4

What are the contents of the infratemporal fossa?

Answer 4

Inferior portion of temporalis muscle, lateral/medial pterygoid muscles, maxillary artery, pterygoid venous plexus

Nerves: inferior alveolar, lingual, buccal, chorda tympani (CN VII), and otic ganglion

Question 5

What are the branches of the mandibular part (1st part) of the maxillary artery?

Answer 5

Deep auricular, anterior tympanic, inferior alveolar (gives off mylohyoid and mental arteries), middle meningeal, and accessory meningeal arteries

Question 6

What are the branches of the pterygoid part (2nd part) of the maxillary artery?

Answer 6

Deep temporal, pterygoid branches, masseteric, and buccal arteries

Question 7

The muscles of mastication are innervated by what nerve?

Answer 7

CN V3

Question 8

What are the paired muscles of mastication?

Answer 8

Temporalis, masseter, lateral/medial pterygoid muscles

Question 9

What is the function of the masseter muscle?

Answer 9

Elevates mandible; assists in protraction, retraction, and side-to-side motion

Question 10

What is the function of the temporalis muscle?

Answer 10

Vertical (anterior) Fibers: elevate mandible

Horizontal (posterior) Fibers: retract mandible

Unilaterally: lateral movement of mandible

Question 11

What is the function of the lateral pterygoid muscle?

Answer 11

Bilateral: protrudes mandible and opens mouth

Unilateral: alternating actions, along with ipsilateral medial pterygoid, results in side-to-side movements necessary for grinding

Question 12

What is the function of the medial pterygoid muscle?

Answer 12

Bilateral: elevation of mandible; also acts with lateral pterygoid to assist in protrusion of mandible

Unilateral: acts with ipsilateral lateral pterygoid to protrude mandible and produce medial movement toward the opposite side; alternating actions between right and left sides results in side-to-side chewing movements

Question 13

What is the function of the digastric muscle?

Answer 13

Elevates the hyoid bone (during swallowing) and assists in opening mandible

Question 14

What is the function of the geniohyoid muscle?

Answer 14

Draws hyoid bone forward (during swallowing) and assists in opening of mandible

Question 15

What is the function of the mylohyoid muscle?

Answer 15

Tightens and elevates the oral floor, draws hyoid bone forward (during swallowing), and assists in opening the mandible and moving it from side-to-side (mastication)

Question 16

What is the function of the stylohyoid muscle?

Answer 16

Elevates the hyoid bone (during swallowing) and assists in opening mandible

Question 17

What is the function of the sternohyoid muscle?

Answer 17

Depresses (fixes) the hyoid bone and depresses the larynx and hyoid bone (for phonation and terminal phase of swallowing)

Question 18

What is the function of the sternothyroid muscle?

Answer 18

Draws the larynx and hyoid bone downward (fixes the hyoid bone) and depresses the larynx and hyoid bone (for phonation and the terminal phase of swallowing)

Question 19

What is the function of the thyrohyoid muscle?

Answer 19

Depresses and fixes the hyoid bone and raises the larynx during swallowing

Question 20

What is the function of the omohyoid muscle?

Answer 20

Depresses (fixes) the hyoid bone, draws the larynx and hyoid bone downward (for phonation and the terminal phase of swallowing), and tenses the cervical fascia with its intermediate tendon and maintains patency of the IJV

Question 21

What muscles elevate the mandible?

Answer 21

Temporalis, masseter, and medial pterygoid muscles

Question 22

What muscles depress the mandible?

Answer 22

Lateral pterygoids, suprahyoid, and infrahyoid muscles

Question 23

What muscles protract the mandible?

Answer 23

Lateral pterygoids, masseter, and medial pterygoid muscles

Question 24

What muscles retract the mandible?

Answer 24

Temporalis and masseter muscles

Question 25

What muscles are responsible for lateral movements of the mandible?

Answer 25

Ipsilateral temporalis and masseter and the contralateral pterygoids

Question 26

For an inferior alveolar nerve block, where should you inject the medicine?

Answer 26

Between the coronoid notch and the pterygomandibular raphe