Floor of the mouth and Tongue

Question 1

Describe the boundaries of the oral cavity

Answer 1

lips, oropharynx, cheeks, tongue/ mylohyoid muscles

Question 2

describe the contents of the floor of the mouth

Answer 2

formed of a muscular diaphragm, created by paired mylohyoid muscles
these muscles create a U shape, attaching to the mylohyoid line and the hyoid bone

geniohyoid muscle sits superior to this, inferior to the tongue- attaching to the inferior mental spine to hyoid bone

Question 3

what is the superior surface of the tongue covered in- housing taste buds?

Answer 3

lingual papillae:
fungiform
follate (posterior and lateral surfaces)
vallate (largest, V shaped, anterior to terminal sulcus)
filliform (only papilla without taste buds)

Question 4

what structures can be seen on the inferior surface of the tongue?

Answer 4

inferior surface of the tongue:
-frenulum- midline, continuous with mucosa of floor of the mouth
- lingual vein on each side of frenulum
- sublingual papilla- includes opening of submandibular duct

Question 5

describe the organisation of muscles of the tongue

Answer 5

tongue is made up of intrinsic and extrinsic muscles that are paired and separated by the sagittal septum

Question 6

what is the function of intrinsic muscles of the tongue and name 4 of these?

Answer 6

intrinsic muscles change the shape of the tongue
- superior longitudinal
- vertical
- transverse
- inferior longitudinal

superior and inferior longitudinal made the tongue short and thick
vertical and transverse muscles make the tongue long and thin

Question 7

what is the function of extrinsic muscles of the tongue?

Answer 7

extrinsic muscles are responsible for protruding, retracting, elevating and depressing the tongue

Question 8

name the 4 extrinsic muscles of the tongue

Answer 8

• palatoglossus
• styloglossus
• hypoglossus
• genioglossus

Question 9

describe the origin and insertion and function of genioglossus

Answer 9

origin- superior mental spine of mandible
insertion- superior fibres insert with intrinsic muscles of tongue, inferior fibres insert to hyoid bone
function- protruding tongue

Question 10

describe the origin, insertion and function of hypoglossus

Answer 10

origin- greater horn of hyoid
insertion- intrinsic muscles on lateral aspect of tongue
function- depressing tongue

Question 11

which blood vessel runs between hypoglossus and genioglossus?

Answer 11

lingual artery (from ECA)

Question 12

Which 2 nerves enter the external surface of hypoglossus?

Answer 12

hypoglossal and lingual nerves enter the ongue on the external surface of hypoglossus

Question 13

describe the origin, insertion and function of styloglossus

Answer 13

origin- styloid process of temporal bone
insertion- intrinsic muscles of tongue and superior fibres of hypoglossus
function- elevating and retracting tongue

Question 14

describe the origin, insertion and function of palatoglossus

Answer 14

origin- palatine aponeurosis (posterior border of hard palate
insertion- intrinsic muscles on lateral surface of tongue

function- depress soft palate towards tongue

Question 15

describe the innervation of the tongue

Answer 15

motor: all supplied by hypoglossal (CN XII) except palatoglossal (supplied by vagus nerve- CN X)

sensory:
anterior 2/3- mandibular nerve (CNV3)
posterior 1/3- glossopharyngeal (CN IX)

special sensory:
anterior 2/3- facial nerve via chorda tympani (CN V)
posterior 1/3- glossopharyngeal (CN IX)

Question 16

describe the blood supply and venous drainage of the tongue

Answer 16

blood supply of the tongue- lingual artery (from ECA)
venous drainage- deep lingual and dorsal lingual veins (both to IJV)