T2L2 neck and oral cavity

Question 1

oral cavity

Answer 1

• continuous with the nasal cavities superiorly and the pharynx inferiorly

Question 2

oral cavity divided into ___

Answer 2

outer oral vestibule and inner oral cavity.

• the outer vestibule includes lips and cheeks
• inner oral cavity is enclosed by the teeth
• roof included hard and soft palate

muscles of the soft palate create the arches of the oral cavity (palatoglossal arch)

floor of cavity formed by muscles - mylohyoid and geniohyoid and the tongue - and it contains submandibular and sublingual glands

Question 3

tongue

Answer 3

divisions: demarked by v shape sulcus
1. anterior 2/3 (oral)
2. posterior 1/3 (pharyngeal)

papillae cover the tongue, and all areas except the filiform have taste buds

• undersurface contains medial fold (frenulum)

Question 4

muscles of the tongue

Answer 4

all muscles paired, as tongue divided into left and right halves.

intrinsic: speech, eating, swallowing
- longitudinal
- transverse
- vertical

extrinsic:
- genioglossus - depresses and protrudes
- hypoglossus - depresses
- styloglossus- retracts tongue
- palatoglossus- elevates back of tongue, compresses soft palate

lingual arteries and lingual veins

Question 5

tongue innervation

Answer 5

anterior 2/3:
taste - CN7 facial special afferent via lingual nerve v3
sensation- lingual nerve v3

posterior 1/3
taste- CN9 glossopharyngeal special afferent
sensation - CN9 (also motor to whole tongue)

Question 6

CN 9 glossopharyngeal

Answer 6

type: sensory, special sensory (taste), motor, visceral
- sensory and taste from posterior 2/3 tongue
- motor to sylopharyngeus
- visceral to parotid gland to stimulate secretion

Question 7

CN 12 hypoglossal

Answer 7

• motor to intrinsic and extrinsic muscles of tongue

exit- hypoglossal canal

Question 8

larynx

Answer 8

• provides protective sphincter for air passages
• aids phonation

formed of cartilages:

• thyroid
• cricoid
• arytenoid
• cuneiform
• corniculate
• epiglottis

and ligaments:

• vocal
• vestibular

nerve supply:
- sensory and motor from vagus

blood supply:
- upper half by the superior thyroid artery and lower half by inferior thyroid artery

Question 9

pharynx

Answer 9

pharynx is the most posterior part of the neck, behind the nasal cavity and the larynx. it is funnel shaped

3 section:

• nasopharynx
• laryngopharynx
• oropharynx

muscles:
superior constrictor
middle constrictor
inferior constrictor

nerve supply:
- motor via vagus except stylopharyngeus (CN9)

Question 10

CN10 vagus

Answer 10

type: sensory, taste, visceral sensory, motor and visceral motor
path: rootlets from medulla, through jugular foramen. continues into carotid sheath
exit: jugular foramen

• sensory from larynx, dura mater
• taste (epiglottis and pharynx)
• visceral sensory (aortic bodies, heart, lungs, midgut, foregut)
• motor (platoglossus, muscles of pharynx and larynx)
• visceral motor (as part of parasympathetic to smooth muscle in glands in pharynx, larynx, thoracic viscera, foregut, midgut)

Question 11

neck contains the mobile _____ bone

Answer 11

hyoid

Question 12

the neck fascia

Answer 12

3 layers:

1. pretracheal fascia
2. prevertebral fascia
3. investing fascia

• reduces spread of infection
• enables structures to move past each other in movement/swallowing
• carotid sheath blends with the pretracheal and prevertebral fascia; it contains:
• carotid arteries
• IJV
• vagus nerve
• carotid sinus nerve
• deep cervical lymph nodes

Question 13

surface anatomy of neck

Answer 13

s15-18

Question 14

arteries through neck

Answer 14

s20

Question 15

venous drainage

Answer 15

IJV drains the brain, face, cervical viscera and neck muscles

• external jugular vein
• anterior jugular vein

Question 16

CN11 accesory

Answer 16

type: motor to sternocleidomastoid and trapezius
exit: jugular foramen

Question 17

CN8 vestibulocochlear

Answer 17

type: sensory somatic afferent for hearing, eqbm, motion
path: divides into vestibular and cochlear nerves
exit: IAM