Question | Answer |
Identify the medial boundary of the parotid bed. | The posterior belly of the digastric m. and other muscles attached to the styloid process (stylopharyngeus and stylohyoid). |
Name 3 major structures embedded in the parotid gland. | The facial n., the external carotid a., and the retromandibular v. |
Outline the path of the parotid duct from start to termination. | The parotid duct passes superficial to the masseter m., dives into the buccal fat pad, pierces the buccinator m. and terminates next to the second maxillary molar in the oral cavity. |
Identify the medial and lateral boundaries of the temporal fossa. | The lateral boundary of the temporal fossa is the posterior aspect of the zygomatic arch while the medial boundary is the greater wing of the sphenoid bone. |
What is the primary component of the temporal fossa? | The temporalis muscle. |
What two spaces on the lateral aspect of the face are defined by the temporalis m.
and it’s fascia? | The superficial and deep temporal spaces/pouches. |
What are the four muscles of mastication? | The temporalis, masseter, lateral ptyergoid and medial pterygoid muscles. |
What are the muscle of mastication? | Temporalis, masseter, lateral ptyergoid, medial pterygoid |
What is the acion of the Temporalis? | elevation/retraction of mandible |
What is the action of the masseter? | elevation oif mandible |
What is the action of the lateral ptyergoid? | depression, protraction and side-to-side movements of the mandible |
What is the action of the medial pterygoid? | elevation, protraction and side-to-side movements of the mandible. |
Name the sole depressor of the mandible. | The lateral ptyergoid muscle. |
What specific nerve supplies motor innervation to these muscles? | The mandibular division of the trigeminal nerve (V3). |
Which of these 4 muscles attach to the lateral pterygoid process? | The lateral pterygoid attaches to the lateral aspect of the lateral pterygoid process (plate); the medial pterygoid attaches to the medial aspect of the lateral ptytergoid process (be sure you can locate these on the skull). |
Which of these 4 muscles inserts into the TMJ? | The lateral pterygoid muscle. |
Which of these 4 muscles attaches to the coronoid process? | The temporalis. |
Which of these 4 muscles attaches to the angle of the mandible? | The masseter laterally and the medial pterygoid medially. |
Which two muscles of mastication form a sling around the ramus of the mandible? | Masseter and medial pterygoid mm. |
What is the primary action of this muscle sling? | Elevate the mandible. |
Name one other group of muscles that also participate in mastication by depressing
the mandible. | The suprahyoids (mylohyoid, anterior/posterior bellies of the diastric, stylohyoid and geniohyoid). |
Identify the lateral collateral ligament of the TMJ | The temporomandibular ligament. |
Identify two accessory ligaments that help retain the stability of the TMJ. | The sphenomandibular and stylomandibular ligaments. |
Which of these two accessory ligaments attach to the lingula of the mandible. | The sphenomandibular ligament. |
What structure separates the TMJ into upper and lower synovial cavities? | The articular disc. |
What bony landmark keeps the condylar head of the mandible within the articular
fossa? | The articular eminence (tubercle) of the temporal bone. |
Where does sensory innervation to the TMJ come from? | The mandibular division of the trigeminal (V3), specifically the auriculotemporal branch. |
What vessels supply the TMJ with blood? | The superficial temporal and maxillary aa. |
Why might TMJ dysfunction cause pain on the side of the face anterior to the ear? | The auriculotemporal nerve passes closely posterior to the TMJ and may be pinched in TMJ articulations. |
List the bony boundaries of the infratemporal fossa | Anterior: posterior surface of maxilla; Superior: inferior surface of the greater wing of the sphenoid; Medial: lateral pterygoid plate of the sphenoid; Lateral: ramus of mandible. |
Identify the medial communication of the ITF. Into what space does it open? | The pterygomaxillary fissure. Into the pterygopalatine fossa. |
List two foramen in the roof of the ITF and what passes through each. | The foramen ovale transmits V3 into the ITF; the foramen spinosum transmits the middle meningeal artery into the cranial cavity. |
Identify the anterior communication of the ITF and what passes through it. | The inferior orbital fissure opens into the orbit and transmits the infraorbital artery. |
List the major contents of the ITF. | The medial & lateral pterygoids; maxillary a.; pterygoid venous plexus; mandibular nerve (V3); and the chorda tympani. |
From what vessel does the maxillary artery arise? | It is one of the two terminal branches of the external carotid artery. |
What are the three clinically important branches and what does each supply? | The inferior alevolar (supplies the lower teeth); the middle meningeal (supplies the dura) and the posterior superior alveolar (supplies the upper teeth and maxillary sinus). |
What is the continuation of the maxillary artery called after it passes through the
pterygomaxillary fissure? | The sphenopalatine artery |
What does this continuation supply? | The nasal cavity. |
What two nerves arise from the trunk of the mandibular nerve in the ITF? | The meningeal branch that passes up through the foramen spinosum with the middle meningeal a.; and the nerve to the medial pterygoid muscle. |
What are the two major divisions of the mandibular nerve and their general
modality? | The anterior (motor) and posterior (sensory) divisions. |
List the specific function of the branches of the anterior division and the one
exception. | The anterior division is motor to the remaining 3 muscles of mastication and one sensory branch - the buccal nerve, sensory to the buccal mucosa of the cheek. |
List the specific function of the branches of the posterior division and the one exception. | The posterior division is general sensory except for the nerve to the mylohyoid that is motor to the anterior belly of the digastric and the mylohoid muscle. |
How does the special sense of taste reach the tongue? | special sensation of taste leave facial nevre travel w temporal bone in chorda tympani which passes middle ear cavity enters lingual nerve w infratemporal fossa. Taste fibers for the anterior 2/3 of the tongue are distributed with the lingual nerve. |
Where does the inferior alveolar nerve enter the mandible? | The mandibular foramen. |
Where does it exit the mandible? | The mental foramen. |
What are the exiting branches called and what is their function. | The mental nn. They are sensory to the skin over the chin region. |
How does the buccal nerve differ from the buccal branch of VII? | The buccal nerve is sensory to the buccal mucosa; the buccal branch of VII is motor to the muscles of mastication in the region of the orbicularis oris (mouth). |
What cranial nerve did the chorda tympani eminate from? | The facial nerve (CN VII). |
How did the chorda tympani enter the ITF? | It enters the ITF via the petrotympanic fissure. |
What type of fibers are carried in the chorda tympani? What do they do? | Special sensory fib ers for taste. They are distriubuted to the anterior 2/3s of the tongue. |
What is the general function of each of the sensory branches off the posterior
division of V3? | Auriculotemporal: sensory to the skin in front of the ear; Lingual: general sensation to the anterior 2/3 of the tongue; and Inferior Alevolar: sensory to the lower teeth. |
What would be the consequence of trauma (severing) the lingual nerve before
the chorda tympani joined it? | The anterior 2/3s of the tongue would lack general sensation (pain, temperature) but would retain the sense of taste. |
What would be the consequence of trauma (severing) the lingual nerve after
the chorda tympani joined it? | The tongue would lack general sensation and taste to the anterior 2/3s. |
What is the otic ganglion and where is it located? | The otic ganglion is one of 4 autonomic ganglia of the head. It is located posterior to the trunk of V3 in the ITF. |
From which cranial nerve did the preganglionic parasympathetic fibers to the otic ganglion arise? What specific nerve brings them to the ganglion? | CN IX (the glossopharyngeal) via the lesser petrosal nerve. |
Through which nerve do the postganglionic parasympathetic fibers travel and to what specific target organ? | The auriculotemporal nerve to the parotid gland. |
How do postganglionic sympathetic fibers reach the parotid gland? | They travel along the external carotid artery from the superior cervical ganglion. |