Tongue muscles Unit 3

tongue primary biological function

taste, mastication, deglutition

tongue is most important and modifies?

most important and most active of articulators

modifies shape of oral cavity

dorsum

upper surface of tongue

longitudinal median sulcus (LMS)

divides dorsum into right and left halves

foramen cecum

small pit towards back of tongue

papillae

projections of dermis covering tongue dorsum

give tongue rough texture

contain taste buds

lingual frenulum

joins inferior tongue and mandible

superior longitudinal

thin layer of oblique and longitudinal muscle fibers

lies just below mucous membrane of dorsum

origin: submucous fibrous tissue close to tongue root

course: fans outward anterior

insert: fibrous membrane at edges of tongue and region near apex

action: elevates, assists in retraction, or s the tip

inferior longitudinal

fibers lie on underside of tongue, laterally

origin: tongue root, some perhaps from hyoid bone

course: anterior

insert: blend with other muscles at apex

action: shortens or s tongue, pulls tip down

transverse

origin: median fibrous septum

course: lateral

insert: submucous fibrous tissue at lateral tongue margins

action: narrows tongue

vertical

origin: base of tongue

course: vertically

insert: membranous cover

action: depress tongue/tip, flattens tongue (pulls tongue down into floor of mouth)

genioglossus

bulk of tongue tissue

strongest and largest extrinsic muscle

origin: inner mandibular surface near symphysis

course: fans up, back, and forward

insert: tip and dorsum of tongue, corpus of hyoid

action: posterior fibers protrude tongue

anterior fibers retract tongue

together they depress tongue

hyoglossus

origin: body and greater horn of hyoid bone

course: vertically, diverging slightly

insert: lateral submucous tissue of posterior ½ of tongue

action: pulls sides of tongue down

styloglossus

origin: styloid process of temporal bone

course: radiates inferiorly and anteriorly

insert: sides of tongue near dorsum

action: draws tongue posteriorly

palatoglossus

also referred to as glossopalatine

origin: anterolateral palatal aponeurosis

course: down

insert: sides of posterior tongue

action: elevates tongue dorsum or depresses the soft palate