Submandibular Triangle Flashcards Preview

Block 6- SHANE > Submandibular Triangle > Flashcards

Flashcards in Submandibular Triangle Deck (58)
1

What is the base of the submandibular triangle?

the inferior border of the mandible

2

What are the sides of the submandibular triangle?

the anterior and posterior bellies of the digastric muscle

3

What nerve innervates all the intrinsic and all the extrinsic muscles of the tongue (except for palatoglossus)?

CN XII

4

What nerve innervates palatoglossus?

CN X

5

What are some of the roles of the mylohyoid muscles?

supporting the floor of the mouth, enabling the tongue to press against the palate in swallowing, and also raising the hyoid

6

What are some of the roles of the geniohyoid muscles?

supporting the hyoid bone, pulling it anteriorly and a bit upward

7

What is the origin of the geniohyoid?

inferior mental spine of the mandible (inserts at the hyoid bone)

8

What is the origin of the mylohyoids?

the mylohyoid line of the mandible (inserts of the hyoid bone)

9

What muscles lie on the superficial surface of the mylohyoids?

the anterior digastric m.

10

What is the mylohyoid innervated by?

nerve to mylohyoid, a branch of the mandibular division of CN V (V3)

11

What does the nerve to mylohyoid branch from?

the inferior alveolar n. as that nerve enters the mandibular foramen

12

Where does the n. to mylohyoid run? Along with?

in the mylohyoid groove along with the mylohyoid branch of the inferior alveolar artery

13

What other muscle does the n. to mylohyoid innervate?

the anterior digastric belly

14

What is the posterior digastric belly innervated by?

facial nerve

15

Why do the anterior and posterior digastric bellies have different innervation?

because they are derived from different pharyngeal arches, I and II

16

What muscle attached to the superior mental spines of the mandible?

genioglossus

17

What muscle attached to the inferior mental spines of the mandible?

geniohyoid

18

What muscle inserts at the digastric fossa?

the anterior digastric

19

What are the possible actions of contraction of the geniohyoid?

the geniohyoid muscles can either pull the hyoid anteriorly and slightly superiorly, but if the hyoid bone is fixed in place by contraction of the infra hyoid muscles, contraction can help to depress the mandible

20

What is the innervation of geniohyoid?

C1 from the cervical plexus (that runs partially with the hypoglossal nerve)

21

What nn. run with the hypoglossal nerve during their course?

the nerve to geniohyoid, nerve to thyrohyoid, and superior root of the nasa cervicalis. The branch of C1 to the geniohyoid extends with the hypoglossal the furthest

22

What are the extrinsic muscles of the tongue?

genioglossus, hyoglossus, styloglossus, and the palatoglossus

23

What are the insertion points of the genioglossus?

primarily in the lateral aspect of the intrinsic tongue muscles but some fibers insert on the hyoid bone

24

Contraction of different groups of genioglossus fibers have different effects on the tongue. What does contraction of its inferior fibers cause?

projection of the tongue out of the mouth, called protraction of the tongue

25

What does contraction of the superior fibers of the genioglossus cause?

pulls the tip of the tongue back inside the mouth and downward, called retraction of the tongue

26

What does contraction of all of the fibers of the genioglossus, contraction of the intrinsic fibers, and other supporting muscles, such as the mylohyoids cause?

causes the tongue to protrude superiorly, pushing against the palate, an action important for propelling a bolus of food posteriorly toward the pharynx

27

What does contraction of the hyoglossus cause? Where does it span

the hyoglossus spans between the greater horn of the hyoid bone and runs anteriorly and superiorly to blend in with the tongue.

Contraction pulls down on the sides of the tongue and a retractor of the tongue, often flattening the tongue

28

What muscle blends into the side of the tongue close to the hyoglossus?

the styloglossus

29

What does contraction of the styloglossus cause?

it pulls the tongue posteriorly

30

What is the anterior tonsillar pillar?

the boundary between the oral cavity and the oropharynx

31

What muscle forms the anterior tonsillar pillar?

palatoglossus (only tongue muscle innervated by CN X)

32

If a person had a lesion of the left hypoglossal nerve, which side would the tongue protrude to if you stuck it out?

the left

33

The deep part of the submandibular gland wraps around which muscle?

the posterior free margin of the mylohyoid

34

Which part of the submandibular gland does the duct originate from?

the deep part

35

Where does the submandibular duct end?

at the sublingual caruncle in the floor of the oral cavity under the tongue. This is where the submandibular gland saliva is secreted. A sublingual caruncle lies on either side of the frenulum

36

Where does the lingual nerve (branch of V3) originate?

the infratemporal fossa

37

Which gland most commonly develops stones?

the submandibular gland

38

What muscle does the lingual nerve descend down at the level of the tongue?

the styloglossus (and slightly on the very superior, lateral aspect of the hyoglossus)

39

The submandibular ganglion is located where?

directly inferior to the lingual nerve, sandwiched in between that and the deep part of the submandibular gland

40

Does the lingual artery course superficial or deep to the hyoglossus?

deep to it

41

What is the function of the lingual nerve?

GSA innervation to the anterior 2/3 of the tongue (to circumvallate papillae) and GSA to the floor of the mouth and lingual gingiva of the mandible

42

Where are the cell bodies of the lingual nerve fibers?

in the semilunar ganglion located in the middle cranial fossa

43

Note on the distribution of the lingual artery and veins in relation to the hyoglossus

the artery is completely deep to the hyoglossus while lingual veins exist on both the superficial and deep surfaces of the hyoglossus. Veins drain to the IJV

44

What provides SA innervation to the taste of the anterior 2/3rd of the tongue and GVE parasympathetic to the submandibular and sublingual glands?

CN VII

45

Where are the cell bodies of the lingual nerve?

in the trigeminal ganglion (aka semilunar, aka Gasser's). This a sensory ganglion

46

What provides GSA innervation to the posterior 1/3 of the tongue?

via CN IX

47

Where do the sensory ganglia of CN IX and X lie?

within or just below the jugular foramen (superior is within, inferior is just below)

48

What branch of CN VII carrier SA taste fibers from the anterior 2/3 of the tongue?

the chorda tympani branch

remember that GSA to the anterior 2/3rd is from the lingual nerve

49

Where are the cell bodies of SA fibers of the tongue found?

within the geniculate ganglion, the peripheral ganglion of the 7th nerve

50

SA and GSA for the posterior 1/3 of the tongue is from what nerve?

CN IX

51

What does the chorda tympani branch of CN VII do?

SA taste fibers to the anterior 2/3 of the tongue and preganglionic parasympathetic fibers from one of the motor nuclei of VII in the brain to the submandibular ganglion. Postganglionic fibers then run from the submandibular ganglion to the submandibular and sublingual lands to provide GVE parasympathetics

52

What nerve does the chorda tympani run with?

the lingual nerve, having joined it in the infra temporal fossa

53

Which is deep to the superficial submandibular gland, the facial artery or facial vein?

the facial artery

54

What foramen does the chorda tympani branch of the facial n. come through?

the stylomastoid foramen

55

Where does the chorda tympani nerve run before joining with the lingual n.?

the infratemporal fossa

56

Describe the course of the chorda tympani n.?

It comes off the brain, through the IAM, through the facial canal in the temporal bone and has its sensory ganglion in the geniculate ganglion. It then goes through SMF into the infra temporal fossa and then meets up with the lingual n. to go the anterior 2/3 of the tongue

57

The lingual n. is a branch of?

V3

58

What is achalasia?

failure of the lower esophageal sphincter to respond to the swallowing reflex