GROWTH AND
DEVELOPMENT OF
CRANIUM

www.indiandentalacademy.com
 Introduction
 Bone growth
 Synchondroses
 Sutures
 Prenatal growth of cranium
 Cranium at birth
 Postnatal growth ...
Robert E Moyer's has defined growth as normal
changes occurring in amount of the living
substances. According to him, grow...
We can put this in the formula of
Development
growth + differentiation +
translocation.

Differentiation: it is the change...
 According to Todd – Growth is an increase in

size and development is progress towards
maturity
 According to J.S. Huxl...
 At the time of birth there are 45 bony elements

separated by cartilage.
 At the end of one year, it is decreased to 22...
Within one year it becomes twice the
size of face
Development of skull, comprising both
the cranium and mandible, is a ble...
Skull entities is composed of
 Neurocranium
Calvaria (desmocranium)
Cranial base (Chondrocranium)
 Face
Masticatory a...
BONE GROWTH

www.indiandentalacademy.com
Before we study the growth of the
various parts of craniofacial complex,
it is important to know how the bone
grows. Bone ...
Bone is composed of two entities
- Osteocytes
Intercellular substance
Osteocytes are two types
Osteoblasts – bone forming...
Endochondral bone formation
At the site where the bone is to be formed,
the mesenchymal cells become closely
packed
to
for...
The cells of the cartilage are at first small
and irregularly arranged.. however in the
area where bone formation is to be...
Some blood vessels of the perichondrium
now invade the calcified cartilaginous
matrix.
They are accompanied by osteogenic
...
The walls of the secondary areolae are
formed by thin layers of calcified matrix
that have not been dissolved.
The
osteoge...
www.indiandentalacademy.com
www.indiandentalacademy.com
INTRAMEMBRANOUS OSSIFICATION
These osteoblasts now lay down a layer of
ossein fibrils embedded in a gelatinous
intercellul...
www.indiandentalacademy.com
Synchondroses

www.indiandentalacademy.com
The cartilage junctions between
two bones are called
synchondroses.
They are important growth sites
cranial base.
www.indi...
Synchondroses found in cranial
base are
1. Spheno - occipital
2. spheno – ethmoidal
3. inter- sphenoidal
4. intra- occipit...
Spheno- occipital – it is the cartilaginous
junction between the sphenoid and the
occipital bones. It is active up to the ...
Inter sphenoid - it is a
cartilaginous band between the
2 parts of the sphenoid bone. It
is believed to ossify at birth.
I...
www.indiandentalacademy.com
www.indiandentalacademy.com
Suture
www.indiandentalacademy.com
They are fibrous joints
comprised of sheets of dense
connective tissue that
separate the bones of calvaria
The sutures hel...
Types of sutures
1.

2.
3.

4.

5.

coronal sutures - it is present between
posterior border of frontal bone and anterior ...
www.indiandentalacademy.com
PRENATAL
GROWTH OF
CRANIUM
www.indiandentalacademy.com
Cranial base growth is due to proliferation of
cartilage and its replacement by bone, primarily
at synchodroses.
Cranial v...
CRANIUM
AT
BIRTH
www.indiandentalacademy.com
At birth, bones of face and jaws are underdeveloped
The ratio between cranium and face is 8:1 at birth,
later the ratio
...
Types of Fontanelle
Anterior Fontanelle
It is the largest
It is seen at the junction of sagittal, coronal and frontal
sutu...
Antero lateral Fontanelle (Sphenoidal)
2 pairs
It ossifies 2 to 3 month after birth
Postero lateral Fontanelle (Mastoid)
2...
www.indiandentalacademy.com
P

Postnatal
growth
Of
cranium
www.indiandentalacademy.com
It is divided into
Brain case
Cranial base.

www.indiandentalacademy.com
Growth of cranial base
Cranial base grows by cartilage growth in the
sphenoethmoidal, inter sphenoethmoidal, spheno
occipi...
www.indiandentalacademy.com
www.indiandentalacademy.com
Growth of brain case
The cranium grows because the brain grows.
By the end of fifth year of life, over 90% of the growth o...
The cranial vault increases in width by “fill in”
ossification of proliferating connective tissues in the
coronal lambdoid...
www.indiandentalacademy.com
CHONDROCRANIAL OSSIFICATION
Approximately 110 ossification centers
appear in the embryonic human skull.
Many of these cent...
Cartilage Dominance theory – By James
Scott,
According to the theory the genetic control is
expressed at cartilage
Scott s...
FUNCTIONAL MATRIX THEORY – BY
MELVIN MOSS, 1960, 1962, 1997
Moss’s idea of growth control is that the growth
control lies ...
Functional cranial
components
Skeletal Unit – Micro skeletal, Macro
skeletal Unit

Functional Matrices
Capsular Matrices
P...
Skeletal Unit

:

The skeletal tissues associated with
a single function are called “the
skeletal unit”. It is comprises o...
functional matrix
The consists of muscles, glands, nerves, vessels,
fat, teeth and the functional spaces

Periosteal matri...
Capsular Matrix
They act directly and passively on their related skeletal units
producing secondary compensatory translati...
In Neuro cranial capsule, the cover is skin
and duramater and in oro-facial capsule, the
skin and mucosa forms the coverin...
The neuro cranial capsule is made up
of skin,connective tissue aponeurotic
layer; loose connective layer,
periosteum, base...
Van Limborgh’s theory, 1970
Limborgh explains the process of growth and
development in the view that combines all the
majo...
Unloaded Nerve theory – by Melvin
Moss
The skeletal units and growth field fulfills the
demands for protection of the mand...
Sero system theory – By petrovic
and stutzmann 1980
the theory states that the influence of somatotropic
complex is STH- S...
Enlow’s counterpart principle
The growth of any given facial or cranial part relates
specifically to another structural an...
Anomalies
of
development
www.indiandentalacademy.com
The calvaria is particularly susceptible to a number of
congenital defects ranging from chromosomal to hormonal in
their e...
In anencephaly absence of the calvaria results in
craniosehisis, characterized by short narrow
chondrocranium.
Afflication...
VARIOUS SYNDROMES AND
DEFECTIVEDEVELOPMENTAL
CONDITIONS
SYNDROME 13 TRISOMY–
EXTRA CHROMOSOME 13 IS PRESENT.
CHARACTERIZED...
Trisomy 18 syndrome (Edwards
syndrome)
Most cases of this trisomy result into
spontaneous abortion
It occurs 1 in 6500 pop...
APERT SYNDROME:
IS A SINGLE GENE DISORDER,
CHARACTERIZED BY PREMATURE FUSION
OF CRANIAL SUTURES, BIZARRE
CRANIOFACIAL APPE...
Craniosynstosis –
It is a condition resulting from premature fusion of
the cranial sutures like Apert syndrome.
In this, h...
The various shapes of the calvaria when
various sutures are prematurely fused are
Normocephaly – is the normal head shape
...
Plagiocephaly – is an asymmetric skull
shape. This may be produced by
unilateral closure of the coronal suture
or unilater...
www.indiandentalacademy.com
Achondroplasia
Characterized by unusual crainio facial
configuration and disproportional short
stature.
Chromosomal disord...
Prognathic mandible that is anteriorly placed
but of normal size, normal gonial angle and
high coronoid process.
In achond...
Marfan’s syndrome
Hereditary disease.
Basically defect of connective tissue
related to defective organization of
collagen....
Down’s syndrome
Flat face .
Large anterior fontanelle, open suture,
small slanting eyes with epicanthal folds,
open mouth,...
Hyperthyroidism
Under functioning of thyroid gland due to failure of
pituitary gland or atrophy or destruction of the
thyr...
Cleidocranial dysplasia: It is a disease of unknown etiology, often hereditary.
Characterized by abnormalities of the skul...
Clinical
Importance
www.indiandentalacademy.com
Craniofacial skeletal growth is very important in
orthodontics since craniofacial morphology are the
source of serious mal...
The growth of the cranium also has direct
effect on the placement of maxilla and
mandible.
The mandible is attached to mid...
www.indiandentalacademy.com
CONCLUSION
A thorough background in craniofacial growth is necessary for
every orthodontist.

Even for those who never wor...
Thank you
For more details please visit
www.indiandentalacademy.co
m

www.indiandentalacademy.com
Upcoming SlideShare
Loading in …5
×

C r growth ash /certified fixed orthodontic courses by Indian dental academy

588 views

Published on


The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

Indian dental academy provides dental crown & Bridge,rotary endodontics,fixed orthodontics,
Dental implants courses.for details pls visit www.indiandentalacademy.com ,or call
0091-9248678078

Published in: Business, Technology
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
588
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
1
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

C r growth ash /certified fixed orthodontic courses by Indian dental academy

  1. 1. GROWTH AND DEVELOPMENT OF CRANIUM www.indiandentalacademy.com
  2. 2.  Introduction  Bone growth  Synchondroses  Sutures  Prenatal growth of cranium  Cranium at birth  Postnatal growth of cranium  Theories of growth  Anomalies of development  Clinical significance  Conclusion www.indiandentalacademy.com
  3. 3. Robert E Moyer's has defined growth as normal changes occurring in amount of the living substances. According to him, growth is the quantitative aspect of biologic development. Development: It refers to all the naturally occurring unidirectional changes in the life of an individual from its existence as a single cell to its elaborations as a multifunctional unit terminating to death. www.indiandentalacademy.com
  4. 4. We can put this in the formula of Development growth + differentiation + translocation. Differentiation: it is the change for generalized cells or tissues to more specialized kinds during development and translocation in change in position. www.indiandentalacademy.com
  5. 5.  According to Todd – Growth is an increase in size and development is progress towards maturity  According to J.S. Huxley – Growth is self- multiplication of living substance.  According to Krogmen – Growth is increase in size, change in proportion and progressive complexity. www.indiandentalacademy.com
  6. 6.  At the time of birth there are 45 bony elements separated by cartilage.  At the end of one year, it is decreased to 22 after the completion of ossification.  14 of these bones are in the face and the remaining 8 form the cranium.  The reduction in the number is due to growth and union at various sutures and endochondral junctions.  At the time of birth, the cranium is 8-9 times larger than the facial portion. www.indiandentalacademy.com
  7. 7. Within one year it becomes twice the size of face Development of skull, comprising both the cranium and mandible, is a blend of morphogenesis and the growth of 3 main skull entities arising from → neural crest and →paraxial mesoderm tissues www.indiandentalacademy.com
  8. 8. Skull entities is composed of  Neurocranium Calvaria (desmocranium) Cranial base (Chondrocranium)  Face Masticatory apparatus. www.indiandentalacademy.com
  9. 9. BONE GROWTH www.indiandentalacademy.com
  10. 10. Before we study the growth of the various parts of craniofacial complex, it is important to know how the bone grows. Bone is always connective tissue The terms cartilaginous or endochondral and membranous or intramembranous identify the type of connective tissue. www.indiandentalacademy.com
  11. 11. Bone is composed of two entities - Osteocytes Intercellular substance Osteocytes are two types Osteoblasts – bone forming cells Osteoclasts – bone resorbing cells. www.indiandentalacademy.com
  12. 12. Endochondral bone formation At the site where the bone is to be formed, the mesenchymal cells become closely packed to form a mesenchymal condensation. Some mesenchymal cells become chondroblasts and lay down hyaline cartilage. Mesenchymal cells on the surface of the cartilage form a membrane called the perichondrium. This membrane is vascular and contains osteogenic cells. www.indiandentalacademy.com
  13. 13. The cells of the cartilage are at first small and irregularly arranged.. however in the area where bone formation is to begin, the cells enlarge considerably. The intercellular substance between the enlarged cartilage cells becomes calcified under the influence of an enzyme called alkaline phosphatase, which secreted by the cartilage cells. The nutrition to the cells is thus cut off and they die, leaving behind empty spaces called primary areolae. www.indiandentalacademy.com
  14. 14. Some blood vessels of the perichondrium now invade the calcified cartilaginous matrix. They are accompanied by osteogenic cells. This mass of vessels and cells is called the periosteal bud. It eats away much of the calcified matrix forming the walls of the primary areolae, and thus creates large cavities called secondary areolae. Thus formation of cartilaginous model takes place. www.indiandentalacademy.com
  15. 15. The walls of the secondary areolae are formed by thin layers of calcified matrix that have not been dissolved. The osteogenic cells become osteoblasts and arrange themselves along the surfaces of these bars, or plates, of calcified cartilaginous matrix. www.indiandentalacademy.com
  16. 16. www.indiandentalacademy.com
  17. 17. www.indiandentalacademy.com
  18. 18. INTRAMEMBRANOUS OSSIFICATION These osteoblasts now lay down a layer of ossein fibrils embedded in a gelatinous intercellular matrix. This material is called osteoid. It is calcified and a lamellus of bone is formed. The osteoblasts now lay down another layer of osteoid over the first lamellus. This is also calcified. Thus two lamellae of bone are formed. Some osteoblasts that get caught between the lamellae form osteocytes. As more lamellae are laid down, bony trabeculae are formed. www.indiandentalacademy.com
  19. 19. www.indiandentalacademy.com
  20. 20. Synchondroses www.indiandentalacademy.com
  21. 21. The cartilage junctions between two bones are called synchondroses. They are important growth sites cranial base. www.indiandentalacademy.com
  22. 22. Synchondroses found in cranial base are 1. Spheno - occipital 2. spheno – ethmoidal 3. inter- sphenoidal 4. intra- occipital www.indiandentalacademy.com
  23. 23. Spheno- occipital – it is the cartilaginous junction between the sphenoid and the occipital bones. It is active up to the age of 12-15 years. The sphenoid and the occipital segments then become fused in the midline area by 20 years of age. spheno- ethmoid - this is a cartilaginous band between the sphenoid and ethmoid bones. It ossifies at 8 to 25 years of age www.indiandentalacademy.com
  24. 24. Inter sphenoid - it is a cartilaginous band between the 2 parts of the sphenoid bone. It is believed to ossify at birth. Intra occipital: - this ossifies by 35 years of age. www.indiandentalacademy.com
  25. 25. www.indiandentalacademy.com
  26. 26. www.indiandentalacademy.com
  27. 27. Suture www.indiandentalacademy.com
  28. 28. They are fibrous joints comprised of sheets of dense connective tissue that separate the bones of calvaria The sutures help the calvaria to change shape during birth www.indiandentalacademy.com
  29. 29. Types of sutures 1. 2. 3. 4. 5. coronal sutures - it is present between posterior border of frontal bone and anterior border of parietal bone Saggital sutures - it is present between upper borders of parietal bones in the median plane lambdoid sutures – it is present between posterior borders of parietal bones and upper border of occipital bone parieto mastoid stutures - it is present between free upper border of mastoid part of temporal bone and posterior part of parietal bone. occipito mastoid sutures – it is present between posterior border of mastoid part of temporal bone and squamous part of occipital bone. www.indiandentalacademy.com
  30. 30. www.indiandentalacademy.com
  31. 31. PRENATAL GROWTH OF CRANIUM www.indiandentalacademy.com
  32. 32. Cranial base growth is due to proliferation of cartilage and its replacement by bone, primarily at synchodroses. Cranial vault or desmocranium growth is accomplished by proliferation of connective tissue between the sutures and its replacement by bone. The periosteum also grows, but it is a limiting membrane determining the size and shape changes. Despite the rapid ossification of the cranial vault in the terminal stages of fetal life, the bones of desmocranium are separated from each other by the fontanels when the child is born. www.indiandentalacademy.com
  33. 33. CRANIUM AT BIRTH www.indiandentalacademy.com
  34. 34. At birth, bones of face and jaws are underdeveloped The ratio between cranium and face is 8:1 at birth, later the ratio decreases to 2:1 in the adult. Bones of cranial vault do not complete their growth during fetal life. The point where more than 2 bones meet the sutures are wide open are called Fontanelle (soft spots). Fontanelle are regions of dense connective tissue where sutures joins. www.indiandentalacademy.com
  35. 35. Types of Fontanelle Anterior Fontanelle It is the largest It is seen at the junction of sagittal, coronal and frontal suture. It is diamond shaped. It ossifies between 1 ½ to 2 years of age posterior Posterior Fontanelle It is triangular in shape and located at the function of sagittal and lambdoid suture. It ossifies 2 to 3 months after birth www.indiandentalacademy.com
  36. 36. Antero lateral Fontanelle (Sphenoidal) 2 pairs It ossifies 2 to 3 month after birth Postero lateral Fontanelle (Mastoid) 2 pairs Ossifies at 1 to 2 year of birth www.indiandentalacademy.com
  37. 37. www.indiandentalacademy.com
  38. 38. P Postnatal growth Of cranium www.indiandentalacademy.com
  39. 39. It is divided into Brain case Cranial base. www.indiandentalacademy.com
  40. 40. Growth of cranial base Cranial base grows by cartilage growth in the sphenoethmoidal, inter sphenoethmoidal, spheno occipital, and intra occipital synchondroses. It follows a neural growth curve, but partially the general growth curve. Activity at the inter sphenoidal synchondroses disappears at birth. Intra occipital synchondrosis closes in the third to fifth year of life. Spheno occipital synchondrosis is a major contributor. Endochondral ossification does not stop here until twentieth year of life. www.indiandentalacademy.com
  41. 41. www.indiandentalacademy.com
  42. 42. www.indiandentalacademy.com
  43. 43. Growth of brain case The cranium grows because the brain grows. By the end of fifth year of life, over 90% of the growth of the brain capsule or brain vault has been achieved. This increased in size is achieved by proliferation and ossification of sutural connective tissue and by appositional growth of individual bones that make up the cranial vault. Apposition can be seen on both the internal and external tables of the cranial bones as they become thicker. . www.indiandentalacademy.com
  44. 44. The cranial vault increases in width by “fill in” ossification of proliferating connective tissues in the coronal lambdoidal, interparetal, parieto shpenoidal and parictotemporal sutures. The mid sagittal sutures between the parietal bones does not close until the middle of the 3rd decade of life. Increase in length of brain may be primarily due to the growth of cranial base with active response at the coronal suture. The brain case grows in height with active response at parietal sutures along with the occipital, temporal, and sphenoidal contiguous osseous structures www.indiandentalacademy.com
  45. 45. www.indiandentalacademy.com
  46. 46. CHONDROCRANIAL OSSIFICATION Approximately 110 ossification centers appear in the embryonic human skull. Many of these centers fuse to produce 45 bones in the neonatal skull. In the young adult, 22 skull bones are recognized. www.indiandentalacademy.com
  47. 47. Cartilage Dominance theory – By James Scott, According to the theory the genetic control is expressed at cartilage Scott said that the cartilaginous sites through out the skull are primary growth centers. The nasal septal cartilage is the pacemaker for growth of the entire nasomaxillary complex. The mandible is considered as a long bone bent into a horseshoe shape with the epiphysis removed, so that the cartilage contributes help and epiphyseal plate at the ends, which are represented by condyles. www.indiandentalacademy.com
  48. 48. FUNCTIONAL MATRIX THEORY – BY MELVIN MOSS, 1960, 1962, 1997 Moss’s idea of growth control is that the growth control lies in adjacent soft tissues and cartilage bones are just sites. The growth of the face occurs as a response to functional needs and is mediated by the soft tissues conceptually the soft tissues growth, bone, and cartilage reacts to it. A number of relatively independent functions are carried out in the craniofacial regions or the human body like, respiration, olfaction, vision, hearing, balance, chewing digestion, swallowing speech and neural integration. www.indiandentalacademy.com
  49. 49. Functional cranial components Skeletal Unit – Micro skeletal, Macro skeletal Unit Functional Matrices Capsular Matrices Periosteal Matrices www.indiandentalacademy.com –
  50. 50. Skeletal Unit : The skeletal tissues associated with a single function are called “the skeletal unit”. It is comprises of bone, cartilage and tendinous tissues. www.indiandentalacademy.com
  51. 51. functional matrix The consists of muscles, glands, nerves, vessels, fat, teeth and the functional spaces Periosteal matrix Their action is directly and actively upon the related skeletal units, alternations in their functional demands produce a secondary compensatory translation of size or shape of their skeletal units. Such processes are brought about by the inter related process of bone deposition and resorption eg. Muscles, blood vessels, nerves glands etc. www.indiandentalacademy.com
  52. 52. Capsular Matrix They act directly and passively on their related skeletal units producing secondary compensatory translation in space. These alterations in spatial position of skeletal units are brought by expansion of the orofacial capsule within which the facial bones arise, grow and are maintained. The facial skeletal units are passively and secondarily moved in space as their enveloping capsule is expanded. Deposition and resorption do not bring about this kind of translative growth. The neurocranial capsule and the oro-facial capsule are examples of capsular matrices. Each of the capsules is an envelope, which contains a series of functional cranial components (skeletal units), which as a whole are sandwiched in between two covering layers. www.indiandentalacademy.com
  53. 53. In Neuro cranial capsule, the cover is skin and duramater and in oro-facial capsule, the skin and mucosa forms the covering. The neurocranial capsule surrounds and protects the neurocranial capsular functional matrix, which is the brain, leptomeninges and CSF. www.indiandentalacademy.com
  54. 54. The neuro cranial capsule is made up of skin,connective tissue aponeurotic layer; loose connective layer, periosteum, base of skull and layers of duramater The orofacial capsule surrounds and protects the oro-naso-pharyngeal spaces, which constitute the matrix. The growth of the facial skull is influenced by the volume and potency of the spaces. www.indiandentalacademy.com
  55. 55. Van Limborgh’s theory, 1970 Limborgh explains the process of growth and development in the view that combines all the major theories. He supports the Moss’s functional Matrix Theory Acknowledges certain concepts of Sicher’s Theory Never did he rule out the genetic theory. www.indiandentalacademy.com
  56. 56. Unloaded Nerve theory – by Melvin Moss The skeletal units and growth field fulfills the demands for protection of the mandibular nerve by formation of bone around . www.indiandentalacademy.com
  57. 57. Sero system theory – By petrovic and stutzmann 1980 the theory states that the influence of somatotropic complex is STH- Somatomedin hormones, sexual hormones and thyroniel hormones on the primary cartilage (epiphyseal cartilages of long bones, cartilages of the nasal septum and sphenoid etc) has the “Cybernetic” form of common. www.indiandentalacademy.com
  58. 58. Enlow’s counterpart principle The growth of any given facial or cranial part relates specifically to another structural and geometric counterparts of the face and cranium. This counterpart principle explains the balanced growth between different regions of the cranium even thought they have different growth rates . Different cranial base parts and their counterparts. Anterior base and naso- maxillary complex. Middle cranial fossa and horizontal pharyngeal space dimensions. Middle cranial fossa and breadth of the ramus. www.indiandentalacademy.com
  59. 59. Anomalies of development www.indiandentalacademy.com
  60. 60. The calvaria is particularly susceptible to a number of congenital defects ranging from chromosomal to hormonal in their etiology. The time of closure of the sutures is altered in many of these afflictions, leading to variable distortion of skull shape In conditions such as cretinism, progeria, trisomy21 and cleidocranial dysostosis there is delayed midline ossification of frontal and saggital sutures of the calvaria, so that anterior fontenelle may remain open into adult life. The resulting brachycephalic skull results in a bossed forehead of highly curved frontal and parietal bones and hypertalorism, partly obscuring the smaller brain case. Another abnormality is premature fusion of sutures (craniosynostosis) Encephaloceles are defects in closure of the foramen caecum at the ethmoid frontal suture allowing hernation of the cranial contents into the face www.indiandentalacademy.com
  61. 61. In anencephaly absence of the calvaria results in craniosehisis, characterized by short narrow chondrocranium. Afflication of cartilage growth produce a reduced cranial base, with increased angulation due to loss of flattening effect of growth of spheno occipital synchondroses. This results in dished deformity of middle 1/3rd of facial skeleton accentuated by a bulging of neurocranium. Achondroplasia, cretinism and Down’s syndrome all produce a similar characteristic facial deformity by their inhibiting effect on chondrocranial growth. Certain forms of dental malocclusion may be related to defects of the chondrocranium that minimize the space available for the maxillary dentition. www.indiandentalacademy.com
  62. 62. VARIOUS SYNDROMES AND DEFECTIVEDEVELOPMENTAL CONDITIONS SYNDROME 13 TRISOMY– EXTRA CHROMOSOME 13 IS PRESENT. CHARACTERIZED BY CLEFT LIP AND PALATE, MICROPTHALMIA (SMALL EYES), MICROCEPHALY WITH SEVERE BRAIN MALFORMATION, CONGENITAL HEART DEFECTS, POLYDACTILY (EXTRA DIGITS) AND A HOST OF OTHER ANOMALIES. www.indiandentalacademy.com
  63. 63. Trisomy 18 syndrome (Edwards syndrome) Most cases of this trisomy result into spontaneous abortion It occurs 1 in 6500 population Early death is the characteristic feature Retarded growth and development Prominent large forehead (occiput ) Small chin Heart defects are commonly seen www.indiandentalacademy.com
  64. 64. APERT SYNDROME: IS A SINGLE GENE DISORDER, CHARACTERIZED BY PREMATURE FUSION OF CRANIAL SUTURES, BIZARRE CRANIOFACIAL APPEARANCE, HIGHLY ARCHED PALATE, SYNDACTYLY (FUSION OF DIGITS) AND VARIOUS OTHER ABNORMALITIES OCCASIONALLY INCLUDING CONGENITAL HEART DEFECTS. THE PATIENT HAS BIZARRE PHYSICAL APPEARANCE AND MENTAL RETARDATION UNLIKELY TO MARRY AND HAVE CHILDREN. www.indiandentalacademy.com
  65. 65. Craniosynstosis – It is a condition resulting from premature fusion of the cranial sutures like Apert syndrome. In this, head shape depends on which sutures are prematurely synostosed, the order in which they synostose and timing at which they synostose. This condition may be prenatal or perinatal in onset or may occur later during infancy or childhood. The earlier the synostoses occur, the more dramatic is the affect on subsequent cranial growth and development. The later synostosis occurs, the less is the effect on the cranial growth and development. www.indiandentalacademy.com
  66. 66. The various shapes of the calvaria when various sutures are prematurely fused are Normocephaly – is the normal head shape Dolicocephaly – if the saggital suture is prematurely synostosed, the calvaria is restricted in its lateral growth and compensates by permitting more passive growth to occur at the coronal and lambdoidal sutures. Brachycephaly – if the cornonal suture is prematurely synostosed, growth is arrested in an antero posterior direction, compensatory growth occurring laterally at the patient saggital suture. www.indiandentalacademy.com
  67. 67. Plagiocephaly – is an asymmetric skull shape. This may be produced by unilateral closure of the coronal suture or unilateral closure of the lamboidal suture. Trigonocephaly – if the metopic suture closes prematurely a triangular calvaria results known as Trigonocepyhaly. www.indiandentalacademy.com
  68. 68. www.indiandentalacademy.com
  69. 69. Achondroplasia Characterized by unusual crainio facial configuration and disproportional short stature. Chromosomal disorder (autosomal dominant) Enlarged calvaria, frontal bossing, large frontal sinus, occipital prominence, normal anterior cranial base length, shortened posterior cranial base length, shortened posterior cranial base length, short upper facial height, short nasal bone, short upper facial height, short maxilla, posterior tilt of nasal floor. www.indiandentalacademy.com
  70. 70. Prognathic mandible that is anteriorly placed but of normal size, normal gonial angle and high coronoid process. In achondroplasia bone preformed in cartilage is affected Membrane bones are not affected. The condition is due to abnormal endochondral bone formation on the development of skull as a whole. The mandible is normal in length because growth a condylar cartilage is appositional. In achondroplasia only interstitially growing cartilage is affected. www.indiandentalacademy.com
  71. 71. Marfan’s syndrome Hereditary disease. Basically defect of connective tissue related to defective organization of collagen. Shape of face is long and narrow. High arched palate. Also seen are excessive length of tubular bones and arachnodactaly or spidery fingers. www.indiandentalacademy.com
  72. 72. Down’s syndrome Flat face . Large anterior fontanelle, open suture, small slanting eyes with epicanthal folds, open mouth, frequent prognathism Sexual underdevelopment, cardiac abnormality and hypermobility of jaws. www.indiandentalacademy.com
  73. 73. Hyperthyroidism Under functioning of thyroid gland due to failure of pituitary gland or atrophy or destruction of the thyroid gland. Decreased ability of the thyroid gland to produce sufficient hormone. Here base of the skull is shortened leading to retraction of the bridge of the nose with flaring. The face is wide failing to develop in the longitudinal direction . The mandible is underdeveloped and the maxilla is overdeveloped . Mental retardation. www.indiandentalacademy.com
  74. 74. Cleidocranial dysplasia: It is a disease of unknown etiology, often hereditary. Characterized by abnormalities of the skull, teeth, jaws and shoulder girdle and stunting of long bones. In the skull the fontanells remain open or at least show delayed closure The sagittal suture is characteristically sunken giving the skull a flat appearance. Shoulder meets in midline. www.indiandentalacademy.com
  75. 75. Clinical Importance www.indiandentalacademy.com
  76. 76. Craniofacial skeletal growth is very important in orthodontics since craniofacial morphology are the source of serious malocclusions. The configuration of the basicranium determines a person’s head form type, which in turn sets up many proportionate features characterizing facial type. If the basicranium is long and narrow, this result in dolicochphalic facial type, which will result anterioposteriorly and vertically, elongated facial profile and this will result in mandibular retrusion. If the basicranium is round, this will result in brachycephalic facial type, this will result in anterioposteriorly and vertically shorter facial profile. This will result in either mandibular protrusion or bimaxillary protrusion. www.indiandentalacademy.com
  77. 77. The growth of the cranium also has direct effect on the placement of maxilla and mandible. The mandible is attached to mid cranial fossa through the condyles. Thus ramus place the mandibular arch in occlusion with the maxillary arch following a pattern set up by the basicranium. Similarly, the nasomaxillary complex is suspended from the anterior cranial fossa. So the configuration of the palate and maxillary arch is thus established by the basicranium www.indiandentalacademy.com
  78. 78. www.indiandentalacademy.com
  79. 79. CONCLUSION A thorough background in craniofacial growth is necessary for every orthodontist. Even for those who never work with children, it is difficult to comprehend conditions observed in adults without understanding the development processes that produced these problems. Craniofacial skeletal growth is very important in orthodontics, since variations in craniofacial morphology are the source of most serious malocclusions and clinical damages. www.indiandentalacademy.com
  80. 80. Thank you For more details please visit www.indiandentalacademy.co m www.indiandentalacademy.com

×