14.3 Infratemporal Fossa

Question 1

Identify the medial pterygoid muscle, its attachments, function and innervation.

Answer 1

• Attaches from medial side of lateral pterygoid plate to medial mandibular angle.
• Functions to elevate mandible, unilateral contraction moves mandible to the contralateral side.
• Innervation: Motor branch of Mandibular nerve (V3)

Question 2

Identify the lateral pterygoid muscle, its attachments, function, and innervation.

Answer 2

-Attaches from lateral side of the lateral pterygoid plate, attaching to the head of the condyle and the articular disk. –Functions to protrude mandible and articular disk onto articular tubercle, unilateral contraction moves mandible to the contralateral side.

Question 3

Locate the root of the mandibular nerve (V3 of Trigeminal)

Locate and Name the 5 main branches of the Mandibular Nerve (V3) in this region

Answer 3

Motor branches (muscles of mastication, tensors, and oral floor)
Buccal
Lingual
Inferior Alveolar
Auriculotemporal

Question 4

Identify the lingual nerve. Describe its origin, course, and function.

Answer 4

• The lingual nerve is a branch off V3.
• Located medial to inferior alveolar nerve, laying on medial pterygoid muscle.
• Provides sensory to anterior 2/3 of the tongue

Question 5

Identify the buccal nerve. Describe its origin, course, and function.

Answer 5

• The (long) buccal nerve is a branch of V3.
• Located between the two heads of the lateral pterygoid. This is the most medial nerve in the infratemporal fossa.
• Functions in sensory innervation to the cheeks.

Question 6

Identify the auriculotemporal nerve. Describe its origin, course, and function.

Answer 6

• The auriculotemporal nerve is a branch of the mandibular nerve (V3)
• Runs with the superficial temporal artery and vein
• Provides sensory innervation to various regions on the side of the head.

Question 7

Identify the chorda tympani. Describe its origin, course, and function.

Answer 7

-Chorda tympani stems from CN VII. joins V3, and provides taste to anterior 2/3 of tongue as well as presynaptic parasympathetics to the submandibular ganglion which serve the submandibular and sublingual glands.

Question 8

Identify the following branches of the maxillary artery, from proximal to distal:

1. Inferior alveolar artery
2. Middle meningeal artery
3. Deep temporal arteries
4. Posterior superior alveolar arteries
5. Sphenopalatine artery
6. Infraorbital artery

Answer 8

1. inferior alveolar artery
2. middle meningeal artery, which typically passes superiorly to the foramen spinosum through a split in the auriculotemporal nerve
3. deep temporal arteries, which pass superiorly into the temporal fossa and are variable in number
4. posterior superior alveolar artery, which enters the posterior aspect of the maxilla
   5,6. infraorbital and sphenopalatine arteries, which are the terminal branches of the maxillary artery passing through the pterygomaxillary

Question 9

Locate the external carotid artery in this region. What is the general pathway of blood flow from this artery in the face?

Answer 9

External Carotid–> Maxillary–> Sphenopalatine–> Posterior Septal and Lateral arteries.
(Posterior septal aa. from external carotid can anastamose with anterior septal aa. from internal carotid)

Question 10

Describe the general pathway of blood from the internal carotid artery.

Answer 10

Internal Carotid–> Opthalmic–> Anterior and Posterior Ethmoid arteries.