The face develops between the 4th and 6th week of embryonic development from structures including the frontonasal process, mandibular arches, and maxillary processes. Between the 6th and 12th week, the palate begins to form through the fusion of the palatal shelves, separating the nasal and oral cavities. Abnormalities can occur if the fusion of structures like the medial nasal processes, mandibular arches, or palatal shelves is incomplete, leading to cleft lip, cleft palate, or other anomalies. A thorough understanding of normal facial development aids in diagnosing and treating congenital defects.

1. Development Of Face
DR. ARUN PANWAR
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2. Introduction 2

3. 3

4. Background
 The external human face develops between the 4th and 6th week of
embryonic development.
 The development of the face is completed by the 6th week.
 Between the 6th and 8th week, the palate begins to develop.
 There is a complete distinction between the nasal and oral cavities. by
12th week.
 There are two important tissue structures involved in development of the
nose and face – the pharyngeal arches and neural crest cells.
 In the developing embryo, there are six pharyngeal arches.
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5.  The stomadeum (future mouth) is a depression bounded
 cranially by a bulging produced by the brain and caudally
by a bulging produced by the pericardial cavity.
 Three prominances appear around the stomadeum. These
are the frontonasal process and right and left mandibular
arches (first pharyngeal arches).
 Face is derived from the following structures:
 The frontonasal process and
 The mandibular arch of each side.
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6.  Each mandibular arch forms the lateral wall of the
stomadeum.
 This arch gives off a bud from its dorsal end. Its
called maxillary process.
 Mesoderm covering the developing forebrain
proliferates and forms a downward projection that
overlaps the upper part of the stomadeum. This
downward projection is called frontonasal process.
 The Ectoderm over the frontonasal process shows
localized thickenings called nasal placodes.
 These nasal placodes soon sink below the surface
to form nasal pits.
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7.  The Ectoderm over the frontonasal process shows
localized thickenings called nasal placodes.
 These nasal placodes soon sink below the surface to
form nasal pits.
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8.  These nasal pits are continous with the
stomadeaum below.
 The edges of each pit are raised above the
surface: the medial raised edge is called
medial nasal process and
 Lateral raised edge is called lateral nasal
process.
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9.  The facial proportions are develop during
the fetal period, that is, during the 9th week
of intrauterine life.
 The development and the actual shape of
the face is achieved during infancy
 During childhood the skeletal structure
becomes more prominent and a definitive
shape is obtained.
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10.  Early in the 4th week, two prominent bulges appear on the ventral aspect
of the embryo.
 Five primordial swellings consisting primarily of neural crest derived
mesenchyme appear around the stomadeum and play a significant role in
the development of face.
 Floor of the stomadeum is formed by the buccopharyngeal membrane
while the lateral and ventral walls are formed by the pharyngeal arches.
 The five primordial swellings are-
 unpaired frontonasal process
 paired maxillary process
 paired mandibular process.
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11. 11

12.  Mesenchymal cells proliferate at the margins
of the placodes and produce horse-shoe
shaped swellings around these.
 The ones lying on the medial side are called
the “medial nasal prominences’ and the ones
on the lateral side are called the ‘ lateral nasal
prominences’.
 The placodes are located in depressions
called ‘nasal pits’.
 The lateral nasal process is seperated from
the maxillary process by the nasolacrimal
groove.
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13. Derivatives Of The Facial Components
 The Frontonasal Process Forms The-
1. Forehead
2. The Bridge Of The Nose.
3. Frontal And Nasal Bone.
 The Maxillary Prominences Forms The-
1. Upper Cheek Regions And Most Of The Upper Lips
2. Maxilla, Zygomatic Bone And Secondary Palate.
 The Mandibular Prominence Forms The-
1. Chin
2. Lower Lip
3. Lower Cheek Region
4. Mandible.
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14. Development Of Upper Lip
 The maxillary process fuse with the lateral nasal
process followed by the medial nasal process.
 Mesodermal basis of the lateral part of the upper
lip formed by the maxillary process.
 Mesodermal basis of the medial part of the
upper lip formed by the frontonasal process
called philtrum.
 Nasal pits are now called external nares and
they cutoff from the stomatodeum.
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15. Anomalies
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16. DOUBLE LIP
Also known as “microchelia”
It is a congenital developmental anomaly characterized by the presence of excessive
redundant labial tissues seen more commonly on the upper lip.
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17. CLEFT LIP
UNILATERAL CLEFT
LIP BILATERAL CLEFT LIP
Failure of fusion of medial and lateral nasal
process unilaterally
Failure of fusion of the medial and lateral
nasal process bilaterally
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18. MEDIAN CLEFT LIP/
TRUE HARE LIP
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19. Oblique Facial Cleft 19
Persistence of the groove between the maxillary prominence and
lateral nasal prominence.

20. Development Of Lower Lips
 Mandibular processes of two sides grow
towards each other and fuse in the midline.
 They now form the lower margin of the
stomatodeum.
 Fused mandibular processes give rise to the
lower lip and to the lower jaw
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21. Development defects
 Congenital lip pits
 Van Der Woude Syndrome
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22. MANDIBULAR CLEFT 22

23. Development Of Nose
The nose
merged medial
nasal prominences
(median ridge &
tip)
frontal nasal process
(the bridge)
lateral nasal
prominences
(the alae)
cartilage nasal
capsule
(septum & nasal
conchae)
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24.  Derives Contribution From:
1. Frontonasal Prominences -
Bridge.
2. Medial Nasal Prominences –
Median Bridge And Tip
3. Lateral Nasal Prominences –
Ala Of Nose
 Cartilage Of Nasal Capsule – Septum And
Nasal Conchae.
 Superficial Alar Field – External Alar
Cartilage.
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25. Mesoderm becomes
heaped up in the
median plane to form
the prominence of
the nose.
Simultaneously a
groove appears
between the regions
of the nose and the
bulging forebrain
As the nose
becomes prominent
external nares come
to open downwards
instead of forwards
The external form of
the nose is thus
established.
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26. Developmental Anomalies Of Nose
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27. ARHINIA
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28. BIFID NOSE 28

29. Development Of Palate
 Palatogenesis begins at the end of 5th week of I.U. life and is completed by
12th week.
 Initially, the nasal cavity is continuous with the oral cavity. A series of steps
lead to their separation, and the establishment of the palate.
 The palate is formed by 2 major parts:
1. Primary palate
2. Secondary palate
• As the nose forms, the fusion of the both the medial nasal prominence
creates the intermaxillary segment – which forms the primary palate
(later becomes the anterior 1/3 of the definitive palate).
• The intermaxillary segment also contributes to the labial component of the
philtrum and the upper four incisors.
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30.  The maxillary prominences expand medially to give rise to the palatal
shelves.
 The palatal shelves then fuse with each other in the horizontal plane, and
the nasal septum in the vertical plane, forming the secondary palate.
 The medial edges of the palatal processes fuse with the free lower edge of
the nasal septum , thus separating the two nasal cavities from each other.
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31. Secondary Palate 31
• The mesoderm in the palate undergoes intramembranous ossification to form the hard
palate.
• Ossification does not extend into the most posterior protion which remains as the oft
palate.

32. Palatal Closure
 Fusion begins in 9th week and is completed by 12th week.
 The two palatal processes fuse with each other in the
midline.
 Fusion begins anteriorly and proceeds backwards.
 Epithelium over the palatal shelves is thickened and come
in contact and fuse at the dorsal surface of the hard palate
& continues posteriorly to the soft palate.
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33. Ossification
 Starts at 8th week of I.U. life.
 Spread of bone into mesenchyme of
fused lateral palatal shelves.
 Mid palatal sutures fuse at 10th
weeks of I.U. life.
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34. ANOMALIES OF THE PALATE
Developmental cyst Clefting of Palate
Along the line of fusion Mis-timing of the fusion
Of embryonic process in of 3 palatal components
The palatal region due to environmental
agents or genetic
predisposition.
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35. Median Palatal Rest Cyst 35

36. Globulomaxillary Cyst 36

37. Gingival Cyst of new born (Bohn’s Nodules)
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38. Clefting of the Palate
Cleft palate: An opening in the roof of the mouth (the palate) due to a
failure of the palatal shelves to come fully together from either side and
fuse.
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39. Etiology of Cleft Palate 39
Inadequacy of palatal process
Tongue position Maternal factors
CLEFT PALATE
Secondary rupture Failure of epithelial
Inadequacy of Degeneration
shelf force

40. Heredity Environmental
factors
Malnutrition
a) Monogenic/ single
gene disorder
b)Polygenic/ifactorihe
ritance
c) Chromosomal
abnormalities
Teratogens
•Ethyl Alcohol
•Diphenylhydantoin
•Trimethadione
•Retinoids
•Aminopterin
•Methotrexate
•Smoking
•Hypervitaminosis A
•Infection during
pregnancy
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41. TYPES OF CLEFTS
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Primary palatal cleft
Secondary palatal cleft
Combined unilateral palatal cleft
Combined bilateral palatal
cleft

42.  Cleft palate – can occur in isolation when the palatal shelves fail to fuse in
the midline, or in combination with cleft lip.
 Cleft lip and cleft palate are relatively common, occurring in
approximately 1/1000 births.
 In addition to the cosmetic and psychosocial implications,
 Severe cleft lip/palate can be a cause of death also if a baby is unable to
feed.
 Other complications include recurrent eat infections and speech
impediment.
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43. Summary
 Study of the growth and development of the face helps in the
understanding of the various congenital defects and how they are a
departure from the normal anatomy and physiology.
 Also, provide clues about methods of prevention and development of
treatment plans accordingly.
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44. References
 Human Embryology : Inderbir Singh, 10th edition
 Essentials Of Facial Growth: Enlow & Hans
 Shafer’s Textbook of Oral Pathology
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