Growth is a dynamic process with a stable pattern of changes resulting in the increase in physical size and mass during its coarse of development.

1. GROWTH
&
DEVELOPMENT

2.  Introduction
 Factors affecting growth
 Theories of growth
 Importance of study of growth
 Summary
 Refrences

3. Growth is a dynamic process with a stable pattern of
changes resulting in the increase in physical size and mass during
its coarse of development.
Growth can be defined in certain aspects.
I. We Grow
II. We grow up
III. We grow older

4. An increase in size.
-Todd
The normal changes in the amount of living substances.
-Moyers (1988)
An Increase in size or number.
-Proffit (1986)
An increase , expansion, or extension of any given tissue.
-Pinkham (1994)

5.  Development comprises all the normal sequential series of events
which result in the increased complexity or maturity in the course
of natural progression from a single cell to the multi-functional
organism, ending at death.
 Increase in complexity ( Todd 1931)
 Is in complexity (Proffit 1986)
 All the 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 death (Moyer 1988)
 Addresses the progressive evolution of a tissue (Pinkham1994) .

6. FACTORS AFFECTING GROWTH
 Genetic Factor
 Hormone
 Nutrition
 Extra-cranial & intra-cranial Pressure
 Muscular Function
 Growth Factor
 Illness
 Climate & Seasonal Effect
 Adult Physique
 Socio-economic Factor
 Exercise
 Family size
 Birth Order
 Secular trend
 Psychological disturbances
 Maternal factors

7.  Genetic Factor
Gene contained within the nucleus of each cell are said to be
necessary to produce an entire organisms and primarily
responsible for the normal growth.
It is believed that size of birth relates to about 18% to the
genome of fetus, 20% to the maternal genome, 32% to the
maternal environmental factors and remaining 30% to
unknown factors.
After birth infants growth rate is no longer dependent on
maternal factors but related to his own genetic makeup.
During adolescence growth co-related with the parental size
more strongly.

8.  Extra-cranial & Intra-cranial Pressure:
Any factor affecting physical growth is expected to be
associated with effect on size and shape of cranial vault.
e.g. Raised Intra cranial pressure during infancy results in an
increase cranial circumference.
 Nutrition:
Poor nutrition at critical stage of life may permanently alter
the normal development patterns of many organs and tissue.
Proper nutrition is essential for normal post natal growth
apart from adequate supply of protein, vitamin, minerals,
calcium, Mg, Phosphorus and fluoride are essential fore
proper bone and tooth growth.

9.  Maternal Factors:
Role of uterine constraints or the size of the uterus. The fetus
increase in size and fill the entire uterine as it grows. During the
last month the uterine constraints may limit the growth of the
fetus.
Role of Placenta: Placenta grow by increasing the cell number
until 35 wks. of Gestation. Latter the growth is due to increase
in cell size.

10.  Hormones:
There are four type of hormone responsible for growth.
Group I
Hormones influencing skeletal bone growth.
 Growth Hormone
 Insulin
 Thyrotropic Hormone

11.  Group II
Hormone responsible for ossification of long bone.
Parathormone
 Group III
Hormone responsible for pubertal growth spurts.
Androgen
Progestrone
Oestrogen
Group IV: Miscellenaous
Prolactin- Synthesis of milk

12.  Muscular Function:
The close relationship between the muscle and the bone growth
is seen due to the fact that the muscle influence the growth both
as a tissue affecting vascular supply and as a force element.
e.g. wrestler's have well developed dental arch where as patient
of myotonic dystrophy have deteriorated craniofacial
morphology
 Growth Factor:
Growth factor are Peptides' (protein factors) that transmits
signal's within and between cell and play a comprehensive role
in the modulation of tissue growth and development.
These factors regulates cell activity by a number of
mechanisms such as migration, differentiation & gene
regulations.

13.  Illness:
Systemic disease has an effect on child growth.
The usual minor illness do not show much of an effect on
growth.
Serious prolonged debilitating illness have a marked effect.
 Season and Circadian Rhythm:
Growth in height is faster in spring then in autumn while
weight increase occur faster in autumn then in spring.
Growth also show Circadian rhythm : growth in height and
eruption of teeth appear to be greater at night then in day
time due to fluctuations of hormone released.

14.  Adult Physique:
There exists a definite relation between physique and
development according to somato-types.
e.g. tall women matures at later age as compared to the
other ones of their age groups.
 Socio-economic factors:
The factors such as nutrition obviously, play a role as growth
factors.
Children living in favorable socio economic condition tend to
be larger, display different type of growth [height: weight] and
show a variation in timing of growth.

15.  Psychological disturbances:
It can lead to inhibition of growth by various methods.
Children experiencing stressful condition display an inhibition
of growth hormone.
Prolonged psychological disturbance retards in growth.

16.  Exercise:
Exercise may be useful for development of motor skill for an
increase in muscle mass for the general well being and fitness
but has no favorable effect on linear growth.
 Family Size & Birth Order:
Studies has shown that the first born babies tend to be
weightless at birth and have smaller stature but higher IQ.
The smaller the family size the better would be the nutrition
and other favorable condition.

17.  Race:
American blacks calcification and eruption of teeth occur earlier
then their white counter parts.
 Secular Trends:
Race, socio-economic level, nutrition, climate and other
differences which leads to change in growth are called
secular trend.
15 yrs old boy are 5 inch taller then boys of 15 yrs old of 50
yrs back.

18. GENETIC THEORY / GENETIC BLUE PRINT
-Brodie 1941
It state that all growth is controlled by genetic influence and
is pre planned.
Examples to support this theory:
Inheritence is polygenic in nature; predisposition of an
individual to class III malocclusion.
Examples against this theory:
Relationship between genotype and phenotype of man and
apes. Large biological differences observed between two
species with similar karyotypes.

19. SUTURAL DOMINANCE THEORY / SICHER’S THEORY
SICHER 1955
* He believed that craniofacial growth occur at the sutures.
* This theory regarded suture to be a growth center (center with an ability to
generate tissue separating forces).
* The sutural theory advocated that the craniofacial suture generated tissue
separating forces during growth thereby pushing apart the various bone of
craniofacial complex.
* THIS THEORY IS DISPROVED NOW
* A number of point were raised against this theory.
* When an area of the suture is transplanted to another location the
tissue does not continue to grow.
* Growth takes place in untreated cases of cleft palate even in the
absence of suture.

20. CARTILAGENOUS THEORY / NASAL SEPTAL THEORY
/ SCOTT’S HYPOTHESIS
SCOTT 1953
According to him intrinsic growth controlling factor are present in
cartilage and periosteum with suture being only secondary. He viewed the
cartilaginous site throughout the skull as primary center of growth.
Nasal septal cartilage is the pacemaker for growth of the entire naso-
maxillary complex.
Examples to support this theory
If a part of an epiphyseal plate is transplanted to a different location it will
continue to grow in the new location.
Nasal septal cartilage also show innate growth potential on being
transplanted to another site, removal of nasal septum lead to mid-facial
deformities.
Examples against this theory
Mandibular condylar cartilage does not grow in culture showing that there
are some cartilage that are not growth center but are just site of growth.

21. FUNCTIONAL MATRIX THEORY/MOSS HYPOTHESIS
-(MOSS
1962)
This theory was introduced by Melvin Moss based on functional cranial
component by Van der Klaaus.
This theory claimed that the control for growth was not in cartilage or
bone but in adjacent soft tissue thus emphasizing that neither the
nasal septum nor mandibular condyle are determinant of growth.
“the functional matrix is primary and the origin, development, and
maintenance of skeletal unit is secondary, compensatory and
mechanically obligatory response to change in shape and special
position of its related functional matrix.”
Each function is carried out by a group of soft tissue which are
supported and / or protected by related skeletal element.

22. MOSS FUNCTIONAL MATRIX MODEL

23. EXAMPLE TO SUPPORT THIS THEORY
 Growth of cranial vault is directly a response of growth of brain
 Enlarged or small eye will correspondingly change the size of
orbit
EXAMPLE AGAINST THIS THEORY
 Hydro cephalic patient the size of brain is small but the cranial
vault is bigger

24. VAN LIMBORGH’S THEORY
VAN LIMBORGH 1970
He Suggested The Following Five Factor That He Believed Control Growth:
 Intrinsic genetic factor- they are the genetic control of the skeletal unit
themselves.
 Local epigenetic factor-bone growth is determined by genetic control originating
from adjacent structure, like brain eye etc.
 General epigenetic factor-they are genetic factor determining growth from
distant structure. E.g. sex hormone, growth hormone
 Local environmental factor-they are non genetic factor from local external
environment. E.g. habit
 General environmental factor- they are general non genetic influence such as
nutrition, oxygen.

25. This is summarized in the following six point :
1. Chondrocranial growth is controlled mainly by intrinsic genetic
factor
2. Desmo cranial growth is controlled by intrinsic genetic factor.
3. The cartilaginous part of the skull must be considered as growth
center.
4. Sutural growth is controlled mainly by influence originating from
skull cartilage.
5. Periosteal growth largely depend upon growth of adjacent
structure.
6. Sutural and periosteal growth are additionally governed by local
non genetic environmental influence.

26. ENLOW’S EXPANDING V PRINCIPLE
 Many facial bone or cranial bone including mandible, maxilla,
palate have a v shaped pattern of growth.
 The growth movement and enlargement of this bone occurs
toward the wide ends of “V” as a result of differential deposition
and selective resorption of bone.
 Bone deposition occur on the inner side of wide end of “V” and
bone resorption on the outer surface.
 Deposition also takes place at the end of the two arm of the “V”,
resulting in growth movement toward the end.

27. ENLOW’S COUNTER PART PRINCIPLE
The counterpart principle of craniofacial growth state that the growth
of any facial or cranial part relates specifically to other structure and
geometric counter parts in the face and cranium.

28.  Different parts and their counterparts are:
Parts Counterparts
Nasomaxillary complex Anterior cranial fossa
Horizontal dimension of pharyngeal
space
Middle cranial fossa
Middle cranial fossa Breadth of ramus
Maxillary arch mandibular arch
Bony maxilla Corpus of mandible
Maxillary tuberosity Lingual tuberosity

29. NEUROTROPHISM
BEHRENT, MOSS 1976
The physiology of neurotrophism is based on the fact that nervous
system apart from conducting efferent and afferent is also
concerned with the integrity of body structure
Nerve control of skeletal growth by transmission of substance
through its axon is called neurotrophism.
The nature of neurotropic substance and the process of their
introduction into the target tissue are unknown.
The different type of neurotropic mechanism are:
 Neuro epithelial trophism
 Epithelial growth regeneration is controlled by neuro trophism
 If neurotrophic process is lacking or is deficient abnormal epithelial
growth, orofacial hypoplasia, cleft palate etc occur.
 Neuro visceral trophism
 The salivary gland fat tissue and other organ are tropically regulated.
 Neuromuscular trophism
 At the myoblast stage of differentiation, neural innervation is established
without which further myogenesis usually cannot continue.

30.  To differentiate whether growth changes are normal or abnormal
 Clinician need norms or standards for height, weight, skeletal and dental
development to assess the normalcy of growth in patient.
 Growth doesn’t takes place uniformly at all time.
 There seems to be periods when a sudden acceleration of growth occur.
 This sudden increase in growth is termed as “growth spurts”.
 Physiologic alteration in hormone secretion is believed to be caused for
such accelerated growth.
 Growth modification by means of functional and orthodontic appliances
elicit better response during growth spurt.
 Surgical correction involving the maxilla and mandible should be carried
out only after cessation of the growth spurt.
 Arch expansion is carried out during the maximum growth period.
 Orthodontic treatment must be done earlier in girls as their growth spurt is
early.
 Class II and III malocclusion should be treated during growth spurt.

31. Growth Is A Dynamic Process With A Stable Pattern Of Changes Resulting In
The Increase In Physical Size And Mass During Its Coarse Of Development.
Development Comprises All The Normal Sequential Series Of Events Which
Result In The Increased Complexity Or Maturity In The Course Of Natural
Progression From A Single Cell To The Multi-functional Organism, Ending At
Death.
Genetic Factor, Hormone, Nutrition, Extra-cranial & Intra-cranial Pressure,
Muscular Function, Growth Factor, Illness, Climate & Seasonal Effect, Adult
Physique, Socio-economic Factor, Exercise, Family Size, Birth Order, Secular
Trend, Psychological Disturbances, Maternal Factors Are The Factors Affecting
The Physical Growth.
The Various Theories Of Growth & Development Are Genetic Theory /
Genetic Blue Print, Sutural Dominance Theory / Sicher’s Theory,
Cartilagenous Theory / Nasal Septal Theory / Scott’s Hypothesis, Functional
Matrix Theory/Moss Hypothesis, Van Limborgh’s Theory, Enlow’s Expanding V
Principle, Enlow’s Counter Part Principle, Neurotrophism

32.  Orthodontics Principles & Practice
-B. S. Phulari
 Orthodontics; The Art & Science 5th edition
-S.I. Bhalajhi
 Text book of orthodontics; 2nd edition
-Gurkeerat Singh
 Textbook of pediatric dentistry
- Nikhil Marwah
 Textbook of Pedodontics-
- Shobha Tondon- 2nd edition
 Principle and practice of Pedodontics
- Arathi Rao
 Internet sources

33. THANK YOU