Muscles of Mastication/Infratemporal Fossa

Question 1

What is the function, innervation, and attachment of the masseter?

Answer 1

Function: close (elevate) mandible
Innervation: V3 (mandibular division of trigeminal)
Function: zygomatic arch -> angle of ramus

Question 2

What is the function attachment, supply of temporalis?

Answer 2

Function: close (elevate) mandible, retraction of mandible
Attachment: temporal fossa, coronoid process
Supply: deep temporal arteries, mandibular division (V3), deep temporal nerves, maxillary artery

Question 3

What is the function and innervation of lateral pterygoid?

Answer 3

Function: protrusion and depression of mandible
Innervation: lateral pterygoid nerve from anterior trunk of V3

Question 4

What is the function and innervation of medial pterygoid?

Answer 4

Function: elevation of mandible, protrusion, side to side
Innervation: Innervation: medial pterygoid nerve from anterior trunk of V3

Question 5

What is the joint for masticatory muscles? What type of joint?

Answer 5

Temporomandibular joint
Synovial, modified hinge

Question 6

What is the articular surface of TMJ made of?

Answer 6

Fibrous cartilage

Question 7

What are the ligaments of TMJ?

Answer 7

Temporomandibular (lateral) ligament, stylomandibular ligament, sphenomandibular ligament

Question 8

What is contained within the infratemporal fossa?

Answer 8

*Sphenomandibular ligament, medial and lateral pterygoid
*Maxillary artery and its branches
*Pterygoid venous plexus
*Mandibular nerve (CNV3) and its branches
*One branch of the facial nerve (CN VII): chorda tympani
*One branch of the glossopharyngeal nerve (CN IX): lesser
petrosal nerve
*One branch of Maxillary nerve (CNV2): post. sup. alveolar n.

Question 9

What part of the maxillary artery is not in the infratemporal fossa?

Answer 9

Third part

Question 10

What are the major branches of the first part of the maxillary artery?

Answer 10

Middle meningeal artery, inferior alveolar artery

Question 11

What are the major branches of the second part of the maxillary artery?

Answer 11

Deep temporal arteries, buccal artery

Question 12

If we rupture middle meningeal artery. what can happen?

Answer 12

Extradural hematoma

Question 13

What is the pterygoid venous plexus?

Answer 13

Network of veins between the
medial and lateral pterygoid muscles

Question 14

What procedure should individuals be cautious of the pterygoid plexus?

Answer 14

Oral anesthesia

Question 15

What are key points about the mandibular division of trigeminal nerve?

Answer 15

• Largest of the three subdivision of the trigeminal nerve
  *Both sensory and motor (unlike ophthalmic and maxillary
  nerves)
  *All branches originate in the infratemporal fossa
  *Sensory part originates from the trigeminal ganglion in the
  middle cranial fossa
  *Motor root joins to the mandibular nerve before it leaves
  the foramen ovale

Question 16

What carries taste to anterior 2/3 of tongue?

Answer 16

Chorda tympani

Question 17

What delivers postganglionic parasympathetic fibers from the otic ganglion?

Answer 17

Auricotemporal nerve