2. PRENATAL AND POSTNATAL GROWTH
AND DEVELOPMENT OF
NASOMAXILLARY COMPLEX
PRESENTING BY
B.NITIN KUMAR
PG 1ST Yr student
3. CONTENTS:
1.INTRODUCTION
2.ANATOMY
3.DEFINITIONS
4.PRENATAL GROWTH
PERIOD OF OVUM
PERIOD OF EMBRYO
PERIOD OF FETUS
DEVELOPMENT OF PERIORAL REGION
GROWTH OF PALATE
5.POSTNATAL GROWTH
NASOMAXILLARY COMPLEX
MAXILLARY TUBEROSITY
MAXILLA
PALATE
KEY RIDGE
MAXILLARY SUTURES
ZYGOMATIC BONE
NASAL CAVITY
ORBIT
6.CONCLUSION
7.BIBILOGRAPHY
4. INTRODUCTION
Growth increments and development progress
rates vary considerably during the two major
periods of human being i.e. prenatal and postnatal
With the increasing importance of orthopedic
concepts and growth guidance, the clinical
application of this information is quite apparent
A thorough knowledge of postnatal growth
particularly is essential for the dentist,
pediatrician, endocrinologist, psychologist, teacher
or whoever works with growing child, if he is to
make significant clinical application of this
information
6. ORBIT
• SIX BONES COMPRISE EACH ORBIT
• Sphenoid, ethmoid, lacrimal, frontal, zygomatic and maxilla
• The optic foramen is opening for the optic nerve and ophthalmic
artery
• Through the superior orbital fissure the oculomotor nerve,
trochlear, ophthalmic branch of trigeminal nerve, the abducent
enter the orbit
• The inferior orbital fissure is the entrance to the orbit for
infraorbital nerve
• ETHMOID BONE: forms a part of nasal cavity, nasal septum and
orbit
• It is located anteriorly at the base of cranium and perpendicular
to cribriform plate
• LACRIMAL BONE: these are small and fragile. They are located
anterior portion of the medial orbital wall
• ZYGOMATIC BONE: forms the cheek
7.
8. NASAL
• NASAL BONE: the nasal bones are oblong bones that form
the bridge of nose
• VOMER: form the in posterior and inferior part of nasal
septum
• INFERIOR NASAL CHONCHA: lies in the nasal cavity and
articulates with the maxilla
9. MAXILLA
• The maxilla is comprised of two portions joined by a
median suture. It consists of a body and four process.
• The frontal process and the zygomatic (malar) process join
the frontal and zygomatic bones.
• The alveolar process surrounds and supports the maxillary
teeth, and the palatine process forms the major portion of
the hard palate.
• Posterior to maxillary 3rd molar is the bulging of bone
known as the maxillary tuberosity.
• The median palatine sutures marks the articulation of
right and left palatine process
10.
11. DEFINITIONS
GROWTH
TODD - GROWTH IS AN INCREASE IN SIZE, DEVELOPMENT IN
PROGRESS TOWARDS MATURITY
MOYERS – GROWTH MAY BE DEFINED AS NATURAL
CHANGES IN THE LIVING SUBSTANCES
KROGMAN – INCRESE IN SIZE, CHANGE IN PROPORTION
AND PROGRESSIVE COMPLEXITY
JS HUXLEY- SELF MULTIPLICATION OF LIVING SUBSTANCE
12. DEVELOPMENT:
TODD: DEVELOPMENT IS PROGRESS TOWARDS
MATURITY.
MOYERS: ALL NATURALLY OCCURRING
UNIDIRECTIONAL CHANGES IN THE LIFE OF AN
INDIVIDUAL FROM ITS EXISTENCE AS A SINGLE CELL
TO ITS ELABORATION AS A MULTIFUNCTIONAL UNIT
TERMINATING IN TO DEATH
13. PRENATAL GROWTH
Prenatal life is arbitrarily divided into 3 periods
The period of ovum
The period of embryo
The period of fetus
14. 1.THE PERIOD OF OVUM
It is the period from fertilization to the end of
the 14th day almost 2 weeks
This period consists primarily of cleavage of
the ovum and its attachment to the uterine
wall
At the end of this period the ovum is only
1.5mm
15. 2.THE PERIOD OF EMBRYO
It is from 14thday-56th day
As early as 21 days after conception when the
human embryo is little more than 3 mm in length
the head begins to take shape
The head is primarily made up of prosencephalon
16. The most inferior portion of the prosencephalon is
to become the frontal prominence which
overhangs the developing oral groove
Bounding the oral groove laterally are the
rudimentary maxillary process
Below the oral groove is broad mandibular arch
17. The primitive oral cavity (bounded by the frontal process),
the 2 maxillary process and the mandibular arch are
together called as stomodeum
During 4th week the maxillary process grow forward and
unite with frontonasal process to form the maxillary jaw
since the median nasal process grow downward more
rapidly than the lateral nasal process, the latter do not
contribute to the structures which ultimately form the
upper limb
20. The depression that forms in the mid line of upper
lip is called philtrum. It indicates the line of fusion
of the median nasal and maxillary process
Those primordia responsible for facial
development are readily observed by the 5th week
of life
21. Inferior or caudal to the stomodeum
Maxillary process which are growing towards the
midline to form lateral parts of upper jaw
The medial nasal process and the maxillary
process grow towards each other
In 7th week fusion of maxillary process occur
22. In 8th week nasal septum has narrowed further the
nose is more prominent and external ear may be
seen forming.
The nasal pits are broken through in to the upper
part of the oral cavity and may now be called
nostrils
It is also noted that there is a sharp demarcation
between the lateral nasal and the maxillary
process ( the nasolacrimal groove)as it close over
it is converted in to naso lacrimal duct
23. 3.THE PERIOD OF FETUS
Between 8th and 12th week the fetus triples in
length the eye lids and nostrils form and close.
There is relatively greater increase in mandibular
size and anterioposterior maxilla mandibular
relationship approaches that of a new born infant.
Tremendous acceleration is seen
25. DEVELOPMENT OF PERIORAL REGION
The face at the 5th week is almost as thick as the sheet
of paper
At this time the oral pit is bonded above the frontal
area and below the mandibular arch which appears
shovel shape.
At around 6th week two small oval, raised areas
appear just above the lateral aspect of future mouth
In next 48 hours the centers of the raised areas
become depression as the tissues around them
continue to grow anteriorly
26. The depression deepens in to pits that will
become future nostrils
The tissue between the nasal pits is termed
median nasal process and those lateral are called
lateral nasal process
The maxillary process fuse with the median nasal
process to form the floor of the nostril.
The lateral nasal process enlarge to form the sides
of the nose.
27. GROWTH OF THE PALATE
The palate begins to develop early in week 6 but
the process is not completed until week 12.
The most critical period during palatal
development is the end of 6th week to the
begening of 9th week
Entire palate develops from 2 structures
primary palate
secondary palate
28. The primary palate is the triangular shaped part of
the palate anterior to the incisive foramen
The origin of the primary palate is the deep
portion of the intermaxillary segment which arises
from the fusion of two median nasal prominences
The secondary palate gives rise to hard and soft
palate posterior to incisive foramen
29. The secondary palate arises from paired lateral
palatal shelves of the maxilla
As the nasal septum proliferates downwards and
backwards the shelf like palatal ridge take
advantage of rapid mandibular growth
30. With the tongue mass no longer interposed
between the palatal process the oral nasal
communication is narrowed down
The palatine process continue to grow towards
each other anteriorly and unit with the
downward proliferating nasal septum to form
the hard palate
This fusion progresses from anterior to posterior
and reaches the soft palate
31.
32. POSTNATAL GROWTH
NASOMAXILLARY COMPLEX
There are two basic movements drift and
displacement
Drift is otherwise called cortical remodelling
It is achieved by selective apposition and
resorption of cortical surfaces ( both
endosteal and periosteal)
33. Displacement movement of the entire bone it is
classified as primary and secondary displacement
Primary displacement( translation) is the
movement of bone due to its own growth
Many bones of craniofacial skeleton grow
accordingly to enlow expanding v principle
34. Bone apposition takes place on the inner side of v
and resorption on the outer surface
As the v expands the inner and outer portions not
only come to occupy new positions but also the
bone as a whole has increased in size
During bone growth by primary displacement the
entire bone is relocated to a new position but
resorbed at the surface in the direction of growth
( anterior surface of maxilla) there is bone
apposition at the posterior end to maintain
contact with adjacent bone
36. Enlow- as bone grow by surface deposition in one
direction it is simultaneously displaced in the
opposite direction
Maxilla cannot be considered as a separate bone
instead its growth is best studied taken into
account the whole nasomaxillary complex or
midface it is a complex system of sutures through
which all the bones are in contact
The sutures are zygomatic maxillary
Zygomatic temporal
Zygomatic frontal
Fronto maxillary
Nasomaxillary etc
37. The nasomaxillary complex consists of zygomatic
bone, maxilla( with palate) , nasal bone, part of
frontal ( orbital roof) bone
Motive force behind the growth of maxilla has
been attributed to primary displacement, growth
at synchondroses, sutures , septal cartilage etc
Primary displacement of maxilla is due to growth
of maxillary tuberosity
38. The tuberosity is considered as a major growth site
Cortical deposition at this site pushes against the
posterior structures with a counter anterior thrust
that leads to primary displacement
As the cranial base grows anteriorly and superiorly
the midface grows anteriorly and inferiorly this is
termed secondary displacement
39. Sutural theory proposes that the sutures of the
nasomaxillary complex are the centres of growth
Nasal septal cartilage growth can lead to the
anterior growth shift of the complex
The theory of SCOTT that claims nasal septal
cartilage to be growth centre has been accepted
40. MAXILLARY TUBEROSITY AND
ARCH LENGTHENING
The horizontal lengthening of the bony maxillary arch
is produced by remodeling at the maxillary tuberosity.
It is depository field in which the backward facing
periosteal surface of the tuberosity receives continued
deposits of new bone as long as growth in this part of
the face continues
Maxillary tuberosity is a major site of maxillary
growth. it does not however, provide for the growth
of whole maxilla but relates only to that area
associated with the posterior part of the lengthening
arch.
41. The position of maxillary tuberosity is actually
established by the posterior boundary of the
anterior cranial fossa and any clinically induced
deviation could result in a developmental rebound
The whole maxilla undergoes a simultaneous
process of primary displacement in an anterior and
inferior direction as it grows and lengthens
posteriorly
In the growth of the bony maxillary arch
tuberosity is moving in 3 directions by bone
deposition on the external surface
42. it lengthens posteriorly by deposition on the
posterior facing maxillary tuberosity
it grows laterally by deposits on the buccal
surface
it grows downward by deposition of bone along
the alveolar ridges and also on the lateral side
43.
44. MAXILLA
• The maxilla develops postnatal entirely by
intramembranous ossification. Since there is no
cartilage replacement.
• Growth occurs in two ways
1.By apposition of bone at the sutures that
connect the maxilla to the cranium and cranial base
2.By surface remodelling
45. Maxilla grows downwards and forwards in response
to various forces. It is surprising fact that as maxilla
grows forwards the posterior end is depository to
maintain contact with adjacent bones but the entire
anterior surface of the maxilla becomes resorptive to
maintain the shape and configuration
Bone deposition is seen at the entire inner aspect of
the maxillary arch and at the tuberosity
At the anterior concave surface of maxilla the
periosteal concavity from ANS to point A is depository
and the periosteal surface from point a to alveolar
margin is resorptive
46. The anterior surface of the maxilla till the region of
key ridge is resorptive and is concave facing
downwards and growing inferiorly
Expanding v principle implies that maxilla grows
inferiorly due to deposition on the inner aspect of
maxillary arch and palate and resorptive in the
outer aspect
The frontal process of maxilla and nasal bone that
form the bridge of the nose are depository in the
anterior aspect
47.
48. PALATE
Downward drift of palate is extensive
The shallow palate of the new born is not
retained in the adult. there is enormous change in
both size and shape of the palate with growth
The newborns palate is shallow and the horse
shoe shaped dental arch has equal length and
width
49. As age advances the palate receives extensive
deposition at the root.
The nasal floor is resorptive, nasal roof is
depository
Palatal growth can be explained with the help of
expanding v principle deposition on the inner
aspect of v ( palatal roof) and resorption on the
outer aspect ( nasal floor) expands the v in the
direction of open end
50. The eruption of teeth increases the vertical height
of the alveolar bone and depth of palate it
increases the width of the bone laterally, according
to v principle palate grows in height and width
with the leading surface towards growth
undergoing deposition
51.
52. KEY RIDGE
Vertical crest just below the malar protuberance.
The crest is key ridge
A reversal occurs here
It is important growth site
key ridge is an important site of reversal and
remodelling
53. Although a range of variations occurs in the exact
placement of the reversal line, anterior to it most
of the external surface of the maxillary arch is
resorptive
This is because that part of the bony arch is
concave
54.
55. MAXILLARY SUTURES
Most sutures in the facial complex do not simply
grow in the direction perpendicular to the plane
of suture itself because of the multidirectional
mode of primary displacement and the differential
extents of growth among the various bones , a
slide or slippage of bones along the plane of
interface can be involved
A suture is just another regional site of growth
adapted to its own localized, specialized
circumstances, just as all the other parts of the
bone have their own regional growth processes
56. It is not possible for a bone to grow just at its
sutures as was sometimes implied in years
past. Nor is it possible for above to have
generalized surface growth without sutural
involvement
Another old but invalid idea is that the suture
growth system closes down at a given age but
the bone continues to enlarge simply by
generalized surface deposition
57. To dispel this notion bone addition on surface x
enlarge the surface area of the bone but addition
must also be made by deposits at sutural surface y in
order to maintain morphologic form
It is apparent that it would not be possible for the
bone to enlarge in surface area without corresponding
additions at sutural contacts
58. ZYGOMATIC BONE
As the maxilla is displaced anteriorly, its anterior
surface is resorptive, the zygomatic bone shifts
posteriorly
The anterior surface of the zygomatic bone and
the medial surface (temporal) are resoptive just
like maxilla
The posterior and lateral surfaces are depository
This expands the zygomatic bone bilaterally and
bizygomatic width increases with age
59.
60. NASAL CAVITY
The floor and the lateral walls of nasal cavity are
resorptive with deposition in the medial wall of
maxillary sinus
This expands the nasal cavity
The portion of roof near the olfactory fossa is
depository because endocranial surface is
resorptive
This remodeling pattern lowers the roof of the
nose
The maxillary sinus is resorptive in the lateral wall
and depository in the medial wall
61.
62. ORBIT
The orbit is a complex congregation of bones
The orbit has medial and lateral walls, roof and
floor. In the medial wall of the orbit, lacrimal and
ethmoidal bones are present
As the nasal cavity elongates, medial wall of orbit
receives deposition; it also expands laterally
63. The roof of the orbit is floor of the anterior cranial
fossa and this endocranial surface is resorptive to
accommodate the growing frontal lobe
Compensatory deposition occurs in the orbital roof
to keep this already thin bone intact
Orbit expands by V principle
There is deposition on the inner aspect and
resorption on the outer aspect
64. The supraorbital ridges are depository but the area
below and lateral to it, the anterolateral rim of
supraorbital rim is resorptive.
The lower border of orbit is almost in line with the
nasal floor vertically at birth.
All the bones of the face are secondarily displaced
in downward and forward direction.
Though displaced downward, orbit is
simultaneously moving away by deposits in the
floor.
65. Thus, different parts of the same bone, orbital
surface of maxilla and nasal floor are moving in the
opposite directions with growth.
66. CONCLUSION
• Study of prenatal and postnatal growth of
nasomaxillary complex is important in
diagnosing the defects associated with it and
application of required method to correct the
various defects.
67. BIBILOGRAPHY Orthodontics principles and practice
-- GRABER T.M
Hand book of orthodontics 4th edition
-- ROBERT E MOYERS
Essentials of Facial Growth
-- DONALD H. ENLOW
Textbook of craniofacial growth
-- SRIDHAR PREMKUMAR
Textbook of orthodontics
-- SAMIR E. BISHARA
Contemporary orthodontics
-- WILLIAM R. PROFFIT
Head, neck and dental anatomy
-- MARJORIE J. SHORT, DEBORAH LEVIN
GOLDSTEIN
