This seminar is about the development of face and its devlopmental abnormalites

1. GOOD
MORNING
EVERYONE...

2. Presented by: Divakar vasudev
PG first year.
DEVLOPMENT OF FACE
Guided By: Dr . Hitesh
Hans
Baweja.

3. Contents
1. Fertilization
2. Morula
3. Germ layer and their fates
4. Pharyngeal arches
5. Facial structures
 Nose
 Cheeks
 Eyes
 External ear
 Nasal cavities
 Palate
 Tounge

4. PROCESS OF FERTILIZATION
THE MALE
GAMETE (SPERM)
FUSES WITH THE
FEMALE GAMETE
(OVUM)

5. CLEAVAGE
Cells formed as described above
undergoes series of divisions.
One Cell divides to 2 cell stage
embryo followed by 3 cell 4 cell
stage and then 5 cell stage ., etc .
This process of subdivision of
ovum into smaller cells is called

6. 16 cell Stage
Trophoblas
t
Inner cell
mass
Conversion of morula into Blastocyst
DAY 3
DAY 4

7. Function of Zona Pellucida
 It Prevents the Embryo from sticking to the
Epithelium when it travel down from uterine tube
 Zona pellucida disappears soon after the morula
reaches the utrine lumen.
 ZP prevents the implantation of blastocycst at
abnormal site.

8. Formation of germ layers
 Some of inner cell mass differentiate into
flattened cells that comes into line its free surface
, which constitute the endoderm ( some says that
these are hypoblastic cells ) first germ layer to
be formed.
 Remaining cells becomes columnar , form the
second germ layer, the ectoderm ( some says
these cells as epiblastic cells ) .
DAY 8

9.  There is formation of Amniotic cavity, filled by amniotic
fluid. The roof of the cavity is formed by amniogenic
cells . While the floor is formed by ectoderm
Flattened cells arising from endoderm spread and line
the inside of the blastocystic cavity, which is called as
primary yolk sac .

10.  Cells of the trophoblast give origin to a mass of cells
as called as extraembryonic mesoderm.
 Small cavities appear in the extra-embryonic
mesoderm , Gradually they enlarge to form a larger
cavity called as extra embryonic coelom .
 With its formation EEM splits into 2 parts parietal
EEM and Visceral EEM
 The unsplit part of EEM will for the future connecting
stalk.

11.  Formation of prochordal plate – Near the margin of
disc , the cubical cells of Endoderm becomes
columnar , this is called as prochordal plate
 Soon after the formation of PP at the tail end there
is formation of primitive streak.
DAY 14

12. DAY 16
 DAY 16 th : Intra embryonic mesoderm
formation
 Cells proliferate in the region of PS pass
sideways , pushing themselves in between
ectoderm and endoderm , and forms IEM

13.  Appearance of Bucco pharyngeal and Cloacal
membrane
 In region of prochordal plate, the ectoderm and
endoderm remain in contact ,there is no mesoderm in
the prochordal plate so it remain thin and later forms
buccopharyngeal membrane.
 In the area caudal to the primitive streak , ectoderm
and endoderm remain in contact , and it will form
cloacal membrane.Bucco pharyngeal
membrane
Cloacal
membranePrimitive streak

14. FOLDING OF THE EMBRYODAY 17, 19, 20,
21

15. FATE OF GERM LAYERS
 ECTODERM
 (A) Lining epithelium
 Skin, Including pigment cells
 Mucous membrane of lips, cheeks, gums, part of the
floor of he mouth, part of palate, nasal cavities and
paranasal sinuses.
 Anterior epithelium of cornea, epithelium of conjuctiva,
epithelial layers of ciliary body and iris.
 Outer layer of tympanic memebrane; epithelial lining of
membranous labyrinth including the special end
organs.

16.  (B) Glands
 Exocrine : Sweat glands, Sebaceous glands, parotid ( and
other slivary glands ?), lacrimal gland.
 Endocrine: Hyophysis cerebri, adrenal medulla.
 (C) Other Derivates
 Nails.
 Hairs
 Enamel of teeth.
 Lens of eye; musculature of iris.
 Nervous system including all neurons, neuroglia ( except
mircoglia), and schwann cells ( from neural crest).
 Substance of cornea, sclera and chororids (from neural
crest?)

17.  ENDODERM
 (a) Lining epithelia.
 Epithelium of part of the mouth, part of the palate,
tounge, tonsil, Pharynx, oesophagus, stomach, small
and large intestine and upper part of anal canal.
 Epithelium of pharyngo-tympanic tube, middle ear,
inner layer of tympanic membrane, mastoid antrum
and air cells.
 Epithelium of respiratory tract.
 (b) Glands.
 Thyroid, parathyroid, thymus,

18.  MESODERM
 All connective tissues including loose areolar tissue
filling the interstices between other tissues,
superficial and deep fasica, ligaments, tendons,
aponeuroses, and the dermis of the skin.
 Specialized connective tissue like adipose tissue,
reticular tissue , cartilage and bone.
 Dentine of teeth.
 All muscles (smooth, striated and cardiac) except the
musculature of the iris (ectoderm) and ciliary
muscles ( neural crest?)

19. Pharyngeal
arches
 These are the series of mesodermal thickning
appear around the cranial most part of the
foregut .
 Each of these bars grows ventrally in the floor of
the developing pharynx to fuse with the
corresponding bars of opposite side.
Mandibular arch
2nd arch
Frontonasal
prominenace
Nasal
placode
Maxillary
prominenace
3rd arch
4th week (22nd day) :
Appereance of 1st and
2nd arches
5th week (29th days):
3rd and 4th arches

20. COMPONENTS OF EACH
ARCH
Skeletal
element
Striated
muscle
An arterial
arch
Nerve
element

21. DERIVATIVES OF THE SKELETAL, NERVE MUSCLE
ELEMENTS
Arch Cartilage derivates Nerve
derivates
Muscles derivate
First 1. It is called as Meckel’s cartilage.
2. INCUS and MALLEUS are derived
form dorsal end .
3. ANTERIOR LIGAMENT OF
MALLEUS and
SPHENOMANDIBULAR LIGAMENT
derived form ventral part from its
perichondrium.
4. MESENCHYME forms the bones of
maxilla, mandible, zygomatic bone ,
palatine bone,part of temporal bone .
Mandibular Medial and lateral
pterygoids, Masseter,
Temporalis, Mylohyoid,
Anterior belly of
digastric,Tensor tympani,
Tensor palati
Second 1. Stapes,
2. Styloid process,
3. Stylohyoid ligament,
4. Lesser cornu of hyoid bone,
5. Superior part of body of hyoid bone.
Facial Muscles of face,
Occipitofrontalis,Platysma,St
ylohyoid, Posterior belly of
digastric, Stapedius,
Auricular muscles.
Third 1. Greater cornu of hyoid bone,
2. Lower part of the body of the hyoid
bone.
Glossophary
ngeal
Stylopharyngeus
Fourth
Sixth
Cartilage of layrnx Superior
laryngeal
Recurrent
Muscles of larynx and
pharynx.

22. DEFECTS IN BRANCHIAL ARCH
DEVLOPMENT
 Caudal overgrowth of the second arch
gradually covers the 2nd, 3rd and 4th branchial
cleft. IF IT PERSISTS LEADS TO THE
FORMATION OF CERVICAL CYST &
FISTULA.

23. CLINICAL PICTURE SHOWING
BRANCHIAL CYST

24. VASCULATURE OF PHAYRENGEAL
ARCHES
 Each of the 5 branchial arches contains a pair of blood
vessels that conduct blood from the heart to the brain and
to the posterior tissues through the arch tissues. These are
called aortic arches.

25. FATE OF ECTODERMAL
CLEFTS
 After the formation of the pharyngeal arches, the
region of the neck is marked on the outside by
ectodermal clefts.
 The dorsal part of the first cleft develops into the
epithelial lining of the EAM
 The pinna is formed is formed from the swelling of
hillocks, that arise on the first and second arch.
 The second arch grows much faster than the
succeeding arches and comes to overhang them
and gets fused with these arches and side of the
neck becomes smooth.

26. Fate of pharyngeal pouches

27.  First pouch : Ventral part is obliterated by the
formation of tongue. Its dorsal part along with 2nd
pouch (dorsal part) together forms a diverticulum that
grows towards the region of developing ear called as
tubotympanic recess, its proximal part gives rise to
auditory tube and distal part forms the middle ear
cavity, including the tympanic antrum.
 Second pouch : ventral part forms the tonsil.
 Third pouch: parathyroid gland and thymus.
 Fourth pouch: superior parathyroid gland, thyroid
gland .

28. NERVE SUPPLY

29. DERIVATES OF SKELETAL
ELEMENTS

30. Down Growth of frontonasal process
At 4th week (28th day)

31. Appearance of Mandibular arch and
maxillary process
At 4th week (28th day) : The frontonasal,
maxillary and mandibular process can
be identified.
Lens and nasal placodes are also

32. FURTHER GROWTH AND
APPEARENCE OF LENS AND NASAL
PLACODE
5th week (31-35 days)
Nasal pits are
established.

33. FACE
 Lower lip: Mandibular process grows towards each
other and fuse in a midline.
 Upper lip: Each maxillary process grows and fuse
with each other.
 Narrowing of Frontal nasal process
 Lateral part of the lip is formed from the maxillary
process (mesodermal base) .The overlying skin is
derived from ectoderm covering the process.
 Median part of the lip (philtrum) is formed from
frontonasal process. Ectoderm of maxillary process
however overgrows this mesoderm to meet that of
opposite maxillary process in the midline therefore
the skin of the entire upper lip is supplied by
maxillary nerves.

34. DIAGRAM REPRESENTATION
The muscles of face (including those of lips ) are derived
from mesoderm of the second branchial arch and are,
therefore supplied by facial nerve.

35. NOSE
 Formed by the Frontonasal process, Medial Nasal
process, Lateral nasal process.
 Deeper part of Frontonasal process forms nasal
septum
 Mesoderm becomes heaped up in the median
plane to form nose prominance.
 External nares goes and open downward.

37. CHEEKS
 Maxillary process and mandibular process
undergoes further fusion with each other to form
cheeks.
 Appearance of naso-optic furrow or nasolacrimal
sulcus.
 Formation of nasolacrimal duct.

38. EYES (out line only)
 Lens placode (ectodermal thickening) appears on the
ventrolateral side of the developing forebrain.
 Lens placode sinks below the surface.
 The eyelids are derived from the folds of ectoderm that
are formed above and below the eyes, and by the
mesoderm enclosed with in the folds .
Nasal
pits
Maxillary
process
Mandibular
Process Stomatodeu
m
Nasolacrimal
groove
Eye
Frontonas
al process
7th week : Eye
lids are
established .
Maxillary
process fused
with medial
nasal process
.

39. 8th week : Eyes
shift from lateral
to frontal
position.

40. EXTERNAL EAR
 It is formed around the dorsal part of first
ectodermal cleft.
 Appearance of a series of mesodermal
thickenings ( tubercles of hillocks) on the
mandibular and hyoid arches and they adjoin this
cleft , this forms pinna.
6th week :
Tubercles are
begins to form

41.  The External acoustic meatus is derived from the
dorsal part of the first ectodermal cleft.
 However, its deeper part is formed by the proliferation
of its lining epithelium, which grows towards the middle
ear. Anomalies of ear
Anomalies of the Auricle
1. The development of the auricle may get
arrested at any stage. As a result of this, it may
be totally, or partially absent; it may be
represented as isoated nodules ; or may be
very small . Alternatively it may be very large.
2. Migration of the auricle from its primitive caudo-
ventral position may remain incomplete. It is
associated with the mandibulofacial dysostosis.
Anomalies of External Auditory Meatus
1. There may be stenosis of the meatus over its
whole length or part of it. The lumen may be
closed with fibrous tissue, by cartilage , or by
bone.
2. The normal curvature of the meatus may be
accentuated as result of which the tympanic
membrane cannot be fully seen from the

42. DEVELOPMENT ANOMALIES OF
FACE
Formation of various parts of face involves the fusion of the
diverse components. This fusion is occasionally incomplete
and gives rise to various anomalies.
1. Cleft lip
When maxillary process do not fuse with the medial nasal
process, this gives cleft in the upper lip.
It may be unilateral or bilateral .
Defective part of lower most part of the frontonasal process
gives midline cleft in the upper lip.
When two mandibular process do not fuse with each other ,
lower lip shows midline cleft.

43. Cleft in the upper lip midline cleft in the upper

44. Oblique facial cleft
Non fusion of the maxillary and lateral
nasal process gives rise to cleft running
From the medial angle of the eye to the
mouth.
The nasolacrimal duct is not formed.
Inadequate fusion of the mandibular process
with the maxillary process leads
to abnormally wide mouth (macrostomia).

45. Too much fusion will give rise to microstomia.

46. The nose may be bifid.
This may be associated with median cleft lip.
Both these occur due to bifurcation of the frontonasal process.
Very rarely the nose forms a cylindrical projection,
or proboscis jutting out from just below the forehead.
It is usually associated with with fusion of the two eyes.

47. The entire first arch may remain
underdeveloped on one or more sides,
affecting the lower eyelid, the maxilla, the
mandible, and the external ear. The
prominence of cheek is absent and the ear
may be displaced ventrally and caudally.
There may be presence of cleft palate and of
faulty dentition. The condition is called
mandibulofacial dysostosis, Treacher
collins syndrome or first arch syndrome.
This is genetic condition inherited as
autosomal dominant.
One-half of the face may be underdeveloped
or overdeveloped.

48. The mandible may be small compared to the
rest of the face resulting in receding chin (
retrognathia). In extreme cases it may even
fail to develop ( agnathia).

49. Congenital tumors may be present in relation to the
face. These may represent attempts at duplication of
some part.
The eyes may be widely separated ( hypertelorism).
The nasal bridge may be broad. This condition
results from the presence of excessive tissue in the
fontonasal process.
The lips may show congenital pits or fistulae. The
lips may be double.

50. NASAL CAVITIES
 The nasal cavities are
formed by extension of
the nasal pits.
 Nasal pits deepen to
form the nasal sacs,
which expand both
dorsally and caudally.
 Dorsal part of sac is, at
first separated from
stomatodaeum by a thin
membrane called the
bucconasal membrane.
This soon break down.

51.  Two nasal sacs are at first widely separated from
one another by frontonasal process, the
frontonasal process becomes progressively
narrower.
 The intervening tissue becomes much thinned to
form the nasal septum.
 The lateral wall of the nose is derived, on each
side, from lateral nasal process. The nasal
conchae appear as elevations on the lateral wall
of each nasal cavity.

52. Anomalies of nasal cavity
1.Atresia of cavity. Very rarely may be total
absence of nasal passages.
2.Communication between the cranial and nasal
cavity.
3.Deflection or absence of nasal septum.
4.Communication between mouth and nasal cavity.

53. PALATE
 2 Palatal Processes : From each maxillary
process, a plate-like shelf grows medially called
as palatal process.
 Primitive palate ( premaxilla) : It is formed form
the frontonasal process.
 Mesoderm in the palate undergoes
intramembranous ossification to form the hard
palate. However ossification does not extend into
the most posterior portion, which remains as soft
palate.
10th week: palatal process
and nasal septum fuse with
each other

54. Cleft Palate
Defective fusion of various components of the palate
gives rise to clefts in the palate. These vary
considerably in degree. Clefts of the palate that
extend to its anterior end are associated with cleft
lip . These cleft may be unilateral and bilateral .
The palate is most susceptible between the 7th and
8th weeks.

55. Various types of cleft palate

56. Tounge
 4th week
 2 lingual swellings at the medial most part of the
mandibular arches , tuberculum impar is the
another swelling present in between these 2
swellings.
Lingual
swellings
Tuberculum
impar
Foramen
caecum
Hypobranch
ial
eminenceEpiglottal
eminence
Laryngeal orifice

57.  Thyroglossal duct: It is deen immediately behind the
tuberculum impar , the epithelium proliferate to form a
downward growth which forms the thyroid gland.
 Hypobranchial eminence: Another midline swelling
seen in relation to the 2nd 3rd 4th arches.
 It has 2 parts cranial and caudal , caudal parts forms
the epiglottis.
 Second arch mesoderm gets burried below, and third
arch mesoderm grows over it and fuses with first arch.

58.  Second arch mesoderm gets burried below, and
third arch mesoderm grows over it and fuses with
first arch.

59.  Anterior 2/3rd of the tongue is derived from 1st arch , so
it is supplied by the lingual branch of mandibular
nerve (post –trematic branch of the first arch), and by
chorda tympani which is the (pre-trematic nerve of
this arch.)
 Posterior 1/3rd of tongue is supplied by the
glossopharyngeal nerve, which is the nerve of 3rd
arch.
 Most posterior part of the tongue is supplied by the
superior laryngeal nerve, nerve of 4th arch.
 Musculature of the tongue is derived from the occipital
myotomes.
 Epithelium of the tougue is made up of single layer of
cells first. Later it becomes stratified and papilla
becomes evident.

60. Anomalies of tongue
 Macroglossia ,Microglossia ,Aglossia
 Bifid tongue due to non fusion of lingual swelling.
 Ankyloglossia
 Persistence of the tuberculum impar, seen as red,
rhomboid-shape smooth zone.
 Presence of thyroid tissue in the tonuge
 Remnants of thyroglossal duct may form cyst in
the base of the tongue.
 Surface of the tongue may be fissured.

61. DEVELOPMENT OF SALIVARY
GLANDS
 The major salivary
glands (parotid,
submandibular and
sublingual) begin
development during 6th to
8th week.
 The parotid develops in
the lateral aspects of the
stomodeum, and the
submandibular and
sublingual develop in the
floor of the stomodeum.

62.  Each gland develops through growth from a bud
of oral epithelium into the underlying
mesenchyme.
 The epithelial buds differentiate into extensive
system of solid cords of cells which later form
lumen and become ducts.
 Minor salivary glands develop during the 3rd
prenatal month. They remain as separate acini
scattered in the connective tissue underlying the
oral mucosa.
 Failure of canalisation of ducts before acinar
secretion begins results in retention cysts.

63. Thank
You...!!!