Development of the tongue

1. DEVELOPMENT OF DEVELOPMENT OF
THE TONGUETHE TONGUE
by:by:
Dr. Carmina Romero GranadoDr. Carmina Romero Granado

2. tonguetongue
Largest single muscular Largest single muscular
organ inside the oral organ inside the oral
cavity.cavity.
Originates from the Originates from the
muscles of occipital muscles of occipital
myotomesmyotomes
Innervated by 5Innervated by 5
thth
, 7, 7
thth
, 9, 9
thth

& 10& 10
thth
cranial nerves cranial nerves

3. Extensive innervation is Extensive innervation is
due to the long distance due to the long distance
the muscle cells the muscle cells
migrates to reach the migrates to reach the
tongue & varied tongue & varied
functions performedfunctions performed
Muscles travel in the Muscles travel in the
paths of these various paths of these various
nervesnerves

4. Parts of the tongueParts of the tongue
The first pharyngeal The first pharyngeal
arch tissues forms the arch tissues forms the
anterior (movable) body anterior (movable) body
of the tongueof the tongue
The second & third The second & third
arches form the arches form the
posterior ( immovable) posterior ( immovable)
body & base . body & base .

5. Tissues of the tongue Tissues of the tongue
has 3 parts:has 3 parts:
The central tuberculum The central tuberculum
impar & impar &
Two lateral lingual Two lateral lingual
swellingsswellings

6. Formation of the TongueFormation of the Tongue
The tongue begins to The tongue begins to
develop at about 4 develop at about 4
weeksweeks
Local proliferation of Local proliferation of
the mesenchyme then the mesenchyme then
gives rise to a number gives rise to a number
of swellings in the floor of swellings in the floor
of the mouthof the mouth

7. First, a swelling (First, a swelling (the the
tuberculum impartuberculum impar) )
arises in the midline in arises in the midline in
the mandibular process the mandibular process
and is flanked by two and is flanked by two
other bulges, the other bulges, the lingual lingual
swellingsswellings

8. Very quickly these Very quickly these
lateral lingual swellingslateral lingual swellings
enlarge and merge with enlarge and merge with
each other and the each other and the
tuberculum impartuberculum impar to to
form a large mass from form a large mass from
which the mucous which the mucous
membrane of the membrane of the
anterior two thirds of anterior two thirds of
the tongue is formedthe tongue is formed

9. The root of the tongue The root of the tongue
arises from the arises from the
hypobranchial hypobranchial
eminenceeminence, a large , a large
midline swelling midline swelling
developed from the developed from the
mesenchyme of the mesenchyme of the
third archthird arch

10. Hypobranchial Hypobranchial
eminence is the eminence is the
primordial of the primordial of the
epiglottis (thin plate epiglottis (thin plate
of cartilage in front of cartilage in front
of the glottis that of the glottis that
protects it) during protects it) during
swallowingswallowing

11. The mesenchyme of the The mesenchyme of the
third arch rapidly third arch rapidly
overgrows that of the overgrows that of the
second arch, which is second arch, which is
thereby excluded from thereby excluded from
further involvement in further involvement in
the development of the the development of the
tonguetongue

12. The The hypobranchial hypobranchial
eminenceeminence gives rise to gives rise to
the mucous covering the the mucous covering the
root, or posterior third root, or posterior third
of the tongueof the tongue

13. Some authorities divide Some authorities divide
the the hypobranchial hypobranchial
eminenceeminence into an into an
anterior copula (which anterior copula (which
gives origin to the gives origin to the
mucosa covering the mucosa covering the
root of the tongue) and a root of the tongue) and a
hypobranchial eminencehypobranchial eminence
(which gives rise to the (which gives rise to the
epiglottis)epiglottis)

14. The tongue separates The tongue separates
from the floor of the from the floor of the
mouth by a down mouth by a down
growth of ectoderm growth of ectoderm
around its periphery, around its periphery,
which subsequently which subsequently
degenerates to form the degenerates to form the
lingual sulcus and gives lingual sulcus and gives
the tongue mobilitythe tongue mobility

15. The The musclesmuscles of the of the
tongue have a different tongue have a different
origin: they arise from origin: they arise from
the the occipital somitesoccipital somites, ,
which have migrated which have migrated
forward into the tongue forward into the tongue
area, carrying with them area, carrying with them
their supply, the twelfth their supply, the twelfth
cranial (hypoglossal) cranial (hypoglossal)
nervenerve

16. This unusual development This unusual development
of the tongue explains its of the tongue explains its
innervationinnervation
Since the mucosa of the Since the mucosa of the
anterior two thirds of the anterior two thirds of the
tonguetongue is derived from the is derived from the
first arch, it is supplied by first arch, it is supplied by
the the fifth cranial nerve fifth cranial nerve
(trigeminal nerve),(trigeminal nerve),
whereas the whereas the mucosa of the mucosa of the
posterior third of the posterior third of the
tonguetongue, derived from the , derived from the
third arch, is supplied by third arch, is supplied by
the the ninth cranial nerve ninth cranial nerve
(glossopharyngeal nerve)(glossopharyngeal nerve)

17. The body & base of the tongue differ in The body & base of the tongue differ in
structure of the mucous membrane:structure of the mucous membrane:
 anterior (body)- papillary in natureanterior (body)- papillary in nature
Posterior (base)- lymphatic in naturePosterior (base)- lymphatic in nature
this are separated by a V-shaped sulcus known this are separated by a V-shaped sulcus known
as as sulcus terminalis sulcus terminalis

18. The anterior 2/3 is divide into two lateral The anterior 2/3 is divide into two lateral
halves by a halves by a lingual septum lingual septum w/c is manifested w/c is manifested
externally as externally as median sulcusmedian sulcus
the dorsal mucosa covering the anterior part is the dorsal mucosa covering the anterior part is
velvet like in appearance because of the velvet like in appearance because of the
presence of invaginations & evaginations presence of invaginations & evaginations
known as known as lingual papillalingual papilla

19. Types of lingual papilla:Types of lingual papilla:
4 types of lingual papilla:4 types of lingual papilla:
2.2.FiliformFiliform
3.3.FungiformFungiform
4.4.FoliateFoliate
5.5.circumvalatecircumvalate

25. Have a nice dayHave a nice day
Thank you for listening!!!Thank you for listening!!!