Parotid Gland, Temporal Region, Infratemporal Fossa and TMJ

Question 1

what type of secretion does the parotid gland produce?

Answer 1

thin, watery saliva produced

serous acini only

Question 2

what does the CT capsule of the parotid gland extend as?

Answer 2

stylomandibular ligament

Question 3

what structures pass through the parotid gland? (lateral –> medial)

Answer 3

facial nerve
retromandibular vein
ECA
superficial temporal artery
great auricular nerve branches
maxillary artery

Question 4

what innervates the parotid gland?

Answer 4

parasympathetic secretomotor: glossopharyngeal nerve (CN IX)
sympathetic: plexus around ECA
general sensory: great auricular

Question 5

what does the lesser petrosal nerve carry?

Answer 5

parasympathetic from CN IX

Question 6

what does the glossopharyngeal nerve exit through the jugular foramen with?

Answer 6

vagus nerve

Question 7

what is the route of the partoid duct?

Answer 7

lateral side of masseter below the zygomatic arch
medial turn to pierce the buccal fat pad and buccinator
enters the oral cavity at the upper second molar

Question 8

what are the extracranial branches of the facial nerve (CN VII)?

Answer 8

posterior auricular
branch to posteiror belly of digastric (and stylohyoid
major branches:
- temporal
- zygomatic
- buccal
- marginal mandibular
- cervical

Question 9

what artery do the superficial temporal and maxillary arteries arise from?

Answer 9

ECA

Question 10

what is the retromandibular vein formed from?

Answer 10

union of superficial temporal and maxillary veins

Question 11

what are the muscles of mastication and what innervates them?

Answer 11

temporalis
masseter
medial pterygoid
lateral pterygoid
all innervated by mandibular division of trigeminal (CN V3)

Question 12

what causes elevation of the mandible?

Answer 12

temporalis, masseter and medial peterygoid

head of mandible and disc move backwards and head rotates in lower surface of the disc

Question 13

what causes depression of the mandible?

Answer 13

lateral pterygoid, digastric, geniohyoid, mylohyoid and gravity
head of mandible rotates on under-surface of articular disc and mandible is pulled forwards

Question 14

what causes protrusion of the mandible?

Answer 14

lateral pterygoid (assist from medial pterygoid)
articular disc and head of mandible move forward, movement in upper part of cavity

Question 15

what causes retrusion of the mandible?

Answer 15

posterior fibres of temporalis

articular disc and head of mandible pulled backwards into mandibular fossa

Question 16

what causes lateral chewing?

Answer 16

pterygoids

protrusion and retrusion combined

Question 17

where is temporalis found?

Answer 17

temporal fossa + fascia –> coronoid process and anterior border of ramus of mandible

Question 18

what is the function of temporalis?

Answer 18

elevate mandible (anterior and superior fibres)
retract mandible (posterior fibres)

Question 19

what innervates temporalis?

Answer 19

deep temporal nerves (x2) from anteiror division of mandibular division of trigeminal nerve (CN V3)

Question 20

where is masseter found?

Answer 20

zygomatic arch –> lateral aspect of ramus of mandible

Question 21

what is the function of masseter?

Answer 21

elevate mandible

Question 22

what innervates masseter?

Answer 22

masseteric nerve from anterior division of CN V3

Question 23

where is lateral pterygoid found?

Answer 23

infratemporal surface of greater wing of sphenoid (upper head) and lateral surface of lateral pterygoid plate (lower head) –> neck of mandible and articular disc

Question 24

what innervates lateral pterygoid?

Answer 24

nerve to lateral pterygoid (anterior division of CN V3)

Question 25

what is function of lateral pterygoid?

Answer 25

pulls neck of mandible forwards with articular disc (protrusion = both) helps in lateral chewing movements with medial pterygoid (one side)

Question 26

where is medial pterygoid found?

Answer 26

tubercle of maxilla (superficial head) and medial surface of the lateral pterygoid plate (deep head) --> medial surface of the angle of the mandible

Question 27

what innervates medial pterygoid?

Answer 27

nerve to medial pterygoid (main trunk of CN V3)

Question 28

what does the trigeminal nerve pass through to exit the brain?

Answer 28

foramen ovale

Question 29

what cranial nerve is trigeminal?

Answer 29

CN V

Question 30

what are the terminal branches of the external carotid artery?

Answer 30

maxillary | superficial temporal

Question 31

what are the branches of the external carotid artery? (from inferior to superior)

Answer 31

``` Superior thyroid Ascending pharyngeal Lingual Facial Occipital Posterior auricular Maxillary Superficial temporal ``` --> Some Anatomists Like Freaking Out Poor Medical Students

Question 32

what does the occipital artery supply and what is it's route?

Answer 32

back of scalp | passes under posterior belly of digastric to enter the posterior triangle of neck

Question 33

what does the posterior auricular artery supply?

Answer 33

the scalp

Question 34

what does the ascending pharyngeal artery supply and what is its route?

Answer 34

pharynx | ascends between the internal carotid and pharynx

Question 35

what are the anterior branches of the external carotid artery?

Answer 35

superior thyroid ascending pharyngeal lingual facial

Question 36

what are the posterior branches of the external carotid artery?

Answer 36

occipital posterior auricular ascendng pharyngeal

Question 37

what does the superior thyroid artery give branches to and where does it run?

Answer 37

gives branches to SCM and superior laryngeal artery | runs with the external laryngeal artery

Question 38

what does the lingual artery supply and what is it's route?

Answer 38

oral cavity | crosses deep to hypoglossus and crossed by hypoglossal nerve

Question 39

what does the facial artery supply and where does it run?

Answer 39

superior and inferior labial branches and angular artery to face passes deep to posterior of digastric

Question 40

what does the superficial temporal artery supply and where does it run?

Answer 40

supplies skin over the frontal and temporal regions | ascends in front of the auricle and divides into anterior and posterior branches

Question 41

what are the branches of the maxillary artery?

Answer 41

``` mandibular portion: deep auricular anterior tympanic middle meningeal inferior alveolar accessory meningeal ``` ``` pterygoid portion: masseteric pterygoid anterior and posteiror deep temporal buccal ``` ``` pterygomaxillary portion: sphenopalatine descending palatine infraorbital posterior superior alveolar artery of pterygoid canal pharyngeal ```

Question 42

what is the infratemporal fossa?

Answer 42

space between the base of the skull and the ramus of the mandible

Question 43

what are the boundaries of the infratemporal fossa?

Answer 43

anterior: posterior surface of teh maxilla posterior: styloid process superior: infratemoral surface of the greater wing of sphenoid medial: lateral pterygoid plate lateral: ramus of mandible

Question 44

what are the contents of the infratemporal fossa?

Answer 44

``` lateral and medial pterygoid mandibular division of trigeminal and branches maxillary artery and branches pterygoid venous plexus chorda tympani otic ganglion ```

Question 45

what is the function of medial pterygoid?

Answer 45

assists in elevating the mandible

Question 46

what are the branches of the anterior division of the mandibular division of the trigeminal nerve?

Answer 46

masseteric nerve to lateral pterygoid x2 deep temporal buccal (sensory)

Question 47

what are the branches of the posterior division of the mandibular division of the trigeminal nerve?

Answer 47

auriculotemporal lingual inferior alveolar (branches to mylohyoid)

Question 48

what are the pre-division branches of the mandibular division of the trigeminal nerve?

Answer 48

meningeal nerve to medial pterygoid communicating branch (tensor tympani and tensor veli palatine)

Question 49

what are the three parts of the maxillary artery?

Answer 49

mandibular pterygoid pterygopalatine

Question 50

where is the pterygoid venous plexus found?

Answer 50

surrounds lateral pterygoid

Question 51

what is the pterygoid venous plexus supplied and drained by and what else does it communicate with?

Answer 51

veins from orbit, nasal and oral cavity drained by maxillary vein communicates with cavernous sinus and facial vein (areas supplied by maxillary artery)

Question 52

what is the chorda tympani a branch of?

Answer 52

facial nerve (CN VII)

Question 53

what does the chorda tympani give rise to and what does it supply?

Answer 53

lingual nerve | to supply taste to anterior 2/3rd tongue

Question 54

what is the route of the chorda tympani?

Answer 54

passes through the internal acoustic meatus with the facial nerve (CNVII) travels through the middle ear to pass through the petrotympanic fissure and the infratemporal fossa to join with the lingaul nerve

Question 55

what does the otic ganglion supply?

Answer 55

secretomotor to the parotid gland

Question 56

what type of joint is the temporomandibular joint and what articulates there?

Answer 56

synovial joint with fibrous capsule and articular surfaces covered in fibrocartilage between head of mandible and mandibular fossa and articular tubercle on squamous part of temporal bone

Question 57

what innervates the TMJ?

Answer 57

auriculotemporal nerve | masseteric nerve

Question 58

what divides the cavity of the TMJ, what's its role and what attaches there?

Answer 58

fibrous articular disc increases the congruity of articular surfaces lateral pterygoid attaches to it and the capsule

Question 59

what movements occur between the head of the mandible and the disc?

Answer 59

elevation and depression (hinge)

Question 60

what movements occur at the disc, mandibular fossa and articular processes?

Answer 60

protrusion and retraction (gliding)

Question 61

what movements at the TMJ are required to close the mouth?

Answer 61

elevation and retraction to pull the condyle backwards

Question 62

what movements at the TMJ are required to open the mouth?

Answer 62

depression and protrusion to slide the disc and condyle forwards towards the tubercle

Question 63

what does asynchronous gliding allow?

Answer 63

chewing

Question 64

what is the route of the maxillary artery?

Answer 64

arises behind the neck of mandible, passes between two heads of lateral pterygoid to pass through the pterygomaxillary fissure (fossa)