Growth and development (2)/certified fixed orthodontic courses by Indian dental academy

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GROWTH & DEVELOPMENT
DEFINITIONS AND
TERMINOLOGIES
INDIAN DENTAL ACADEMY
Leader in continuing dental education
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Definition of Growth
 ―Growth refers to increase in size‖ - Todd
 ―Growth usually refers to an increase in size
and number‖ – Proffit
 ―Self multiplication of living substance‖-
J.S.Huxley.
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 ―Growth may be defined as the normal
change in the amount of living substance
 ―Change in any morphological parameter
which is measurable‖- Moss.
 ―Size development , progressive
development
(i.e, evolution, emergence, increase or
expansion)‖- Webster’s dictionary.

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Definition of Development
Development is a progress towards
maturity” – Todd
“Development connotes a maturational
process involving progressive
differentiation at the cellular and tissue
levels” - Enlow

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“Development refers to all
naturally occurring
progressive, unidirectional, sequen
tial changes in the life of an
individual from it’s existence as a
single cell to it’s elaboration as a
multifunctional unit terminating in
death” – Moyers

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Definitions
Morphogenesis – ―A biologic
process having an underlying control at
the cellular and tissue levels‖
Differentiation – ―It is a change from
generalized cells or tissues to a more
specialized kinds during development‖

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•Translocation –
― It is a change in position‖
•Maturation –
―It is the emergence of personal
characteristics and behavioural
phenomenon through growth processes‖

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DIFFERENT KINDS OF
GROWTH
 Size change
 Positional change
 Proportional
change
Functional change
Maturational change
Compositional change

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Timing and sequential change
a. Prenatal growth
b. Postnatal growth
c. Maturity
d .Old age

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Size change- height, weight, girth ,
volume
Positional change-
•Migration of neural crest cells
•Eruption of teeth
•Dropping of diaphragm from 4th
cervical vertebra to the level of 12th
thaoracic vertebra

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Proportional change
Eg-Head of the infant
Functional change
Eg-Secretion , production of enzymes,
hormones

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Maturational change
-Towards a period of stability and
adulthood
Compositional change
Eg-Eye pigmentation

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Timing and sequential change
•Prenatal growth- rapid increase in cell no.
•Postnatal growth- 20 yrs- declining growth-
increasing maturation
•Maturity-period of stability
•Old age
•death

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Major themes of
development
 Changing complexity
 Shifts from competent to fixation
 Shifts from dependent to independent
 Ubiquity of genetic control modulated by
environment

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Changing complexity
 All level of organisation sub-cellular
to the whole organism
 Complexity development
 Orthodontics Mixed dentition period

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Shifts from competent to fixation
 Undifferentiated cells once differentiated
become fixed.
Shifts from dependent to
independent
 Development brings greater independence at
most levels of organisation.

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Ubiquity of genetic control
modulated by environment
 Genetic control of development is
constantly being modified by
environmental interactions

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Correlation between
Growth & Development
 Growth anatomic phenomenon
quantitative
Development physiologic
phenomenon qualitative

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Growth
•Increase in size decrease in
size
eg- thymus gland after puberty
Development process of increasing
complexity.
Development=growth+differenciation+translocation

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Importance of growth and
development to orthodontist
 To understand the etiology of malocclusion
 To assess the health and nutrition of children
 Allows comparison of growth of an individual
child with the growth of other children

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 To identify abnormal occlusal
development at an earlier stage
 use of growth spurts
 Surgery initiation
 Planning of retention regime

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Normal features of
Growth & Development
 pattern
-Differential Growth
-cephalocaudal gradient of growth
 Variability
 Timing, rate & direction

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PATTERN
 Pattern in growth represents proportionality .It
refers not just to a set of proportional
relationships at a point in time but to change
in these proportional relationships over time
 The physical arrangement of the body at any
one time is a pattern of spatially proportioned
parts.

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DIFFERENTIAL GROWTH
Different organs grow at different
rates to a different amount and at
different times.
 Scammon‘s curve of growth
-Richard scammon

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SCAMMON‘S CURVE OF
GROWTH
 LYMPHOID
 NEURAL
 GENERAL
 GENITAL

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CEPHALOCAUDAL GRADIENT
OF GROWTH
• Changes which are a part of normal
growth pattern reflect ―Cephalocaudal
gradient of growth‖
• It implies that there is an axis of
increased growth extending from the
head toward the feet.

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CEPHALOCAUDAL GRADIENT
OF GROWTH

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Growth of head and face

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•It illustrates the change in overall body
proportions during normal growth and
development.
•Imp aspect of pattern is its predictability.

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Predictability
 Predictability of growth pattern is a specific
kind of proportionality that exists at a
particular time and progresses towards
another, at the next time frame with slight
variations.
 Change in growth pattern indicates some
alteration in the expected changes in body
proportions.

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Variability
 No two individuals with the exception of
siamese twins are like.
 Hence it is important to have a ―normal
variability‖ before categorizing people
as normal or abnormal

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Normality
 Normality refers to that which is usually
expected, is ordinarily seen or typical – Moyers
 Normality may not necessarily be ideal.
 Deviation from usual pattern can be used to
express quantitative variability
 This can be done by using ―growth charts‖
•

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Growth chart

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Applications of growth charts.
 Location of an individual relative to the
group can be established.
 Can be used to follow a child over time
and note for any unexpected change in
growth pattern.

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Timing of Growth
 One of the factors for variablity in growth.
 Timing variations arise because biologic clock
of different individuals is different.
 It is influenced by:
 genetics
 sex related differences
 physique related
 environmental influences

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Distance curve
Vs
Velocity curve
Distance curve
Velocity curveAge
Height
Distance Curve (cumulative curve): In this curve growth
can be plotted in height or weight recorded at various
ages.
Velocity Curve(incremental curve): In this by amount
of change in any given interval that is growth incrementwww.indiandentalacademy.com

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Growth spurts
 Defined as periods of growth acceleration
 Sex-linked
 Normal spurts are
 Infantile spurt – at 3 years age
 Juvenile spurt – 7-8 years (females); 8-10 years
(males)
 Pubertal spurt – 10-11 years(females); 18-15 years
(males)
 Growth modulation can be done

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GROWTH STUDIES AND METHODS
OF STUDYING GROWTH.

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• Types of growth data
• Methods of gathering growth data
• Longitudinal growth studies
• Methods of studying bone growth

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Types of growth data.
Opinion
Observations.
Ratings and
rankings.
Quantitative
measurements.
direct data.
indirect data.

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Types of growth data.
• Opinion
It is a clever guess based on experience.
they are the crudest form of scientific
knowledge.
• Observations:
They are useful for studying all or none
phenomenon.they are used in a limited way
when more quantitative data is available.

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• Ratings and rankings:
certain data is difficult to quantify and thus
may be compared to conventional rating
scale .ratings make use of comparisons with
such scales.rankings array data in ordered
sequence according to value.

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Quantitative measurements:
Includes expressing an idea or fact as a
meaningful quantity or numbers.
• Direct data: derived from measurements taken
on living persons or cadaver with a measuring
device.
• Indirect data: derived from measurements
taken from images or reproductions of the
actual person.
• Derived data: obtained by comparing at least
two other measurements.

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Methods of gathering growth
data.
• Longitudinal studies .
• Cross sectional studies.
• Overlapping or semi longitudinal studies.

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Longitudinal studies.
• These are measurements made of the same
person or group at regular intervals through
time.
• Advantages: temporary temporal problems are
smoothed with time,
Variability in development within a group is put
in proper perspective,serial comparison makes
study of specific developmental pattern of
individual possible.
Disadvantages: time
consuming, expensive, sample loss orwww.indiandentalacademy.com

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Cross sectional studies
ADVANTAGES
 Quicker
 Less costly
 Statistical treatment made easier
 Allows repeating
DISADVANTAGES
 Variation in development amongst individuals within
the sample cannot be studied

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Semi longitudinal studies.
• Longitudinal and cross sectional studies can
be combined to to seek the advantages of
both.in this way one might compress 15
years of study into 3 years of gathering
growth data.

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LONGITUDINAL GROWTH
STUDIES.

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Longitudinal growth studies
 Bolton brush growth study
 Burlington growth study
 Michigan growth study
 Denver child growth study
 Iowa child welfare study
 Forsyth twin study
 Meharry growth study

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 Montreal growth study
 Krogman philadelphia growth study
 Fels growth study
 Implant studies
 the mathews implant collection
 the hixon oregon implant study
 Cleft palate study

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Bolton Brush growth study.
• Initiated by Prof T Wingate Todd in 1926
• Aim- studying skeletal development .
• Initiated concurrently by Dr Holly Broadbent Sr in
1929.
• Aim- studying normal development of facial
skeleton.
• Sample size:5000 normal healthy children.
• Records:series of x-rays,casts,dental and medical
examination and psychological tests.

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• The two collections merged officially in 1970.
• In 1975 the Bolton standards of dentofacial development
growth were published by Dr Holly Broadbent jr.
• These standards are a series of averages that represent
optimum facial and developmental growth and form a
baseline for understanding and assessing craniofacial
growth.

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Burlington growth study
• AIM
• Malcclusion
• Evaluate preventive and interceptive orthodontic
treatment.
• Obtain a set of growth records as a database for
future studies.
• Sample size:1632 subjects followed
longitudinally.

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 Records :series of x-
rays, casts,photographs,height and
weight records and medical
examination.
 The original concept for the study was
presented by Robert Moyers& the
records were gathered under Frank
Popovich.

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Burlington growth study
• More than 247 investigations & 322 studies are
based on this growth study
• Longitudinal studies by Thompson & Popovich to
derive cephalometric norms of a representative
sample was based on 210 children followed for 15
years at the Burlington growth center.
• age sex and growth type specific craniofacial
templates were derived and static and dynamic
analysis were proposed on the basis of this study.

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The Iowa child welfare study.
• Sample size:it is a diminishing longitudinal
study which began with 20 males and 15
female 4 year old subjects. Followed till 17
years of age. Non -orthodontically treated
patients of entirely European origin were
used.
• Records:lateral and PA views and dental
casts.
• The study as done under Samir Bishara.

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• Based on this study the changes in facial
dimensions & relationships as well as in
standing height were evaluated.
• The dentofacial relationships of 3 normal facial
types (long, average, short) from 5-25 yrs of
age was described & compared.

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CLEFT PALATE STUDIES.
• LANCASTER PA:includes 850 record sets obtained
annually from birth to 15 years.
• HOSPITAL FOR SICK CHILDREN(Toronto):over
4000 subjects ranging in age from 5-20 years
• .CENTER FOR CRANIOFACIAL
ANOMALIES(Chicago);annual records of 1000
subjects.
• Records include series of x-ray films, casts, medical
and orthodontic treatment records.
• All subjects had surgical repair and minor to extensive
orthodontic treatment.

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Methods of studying bone growth
cephalometry.
anthropometry.
craniometry.
measurement approaches.
autoradiography.
nuclear volume morphometry.
radioisotopes.
polarised light.
fluorescent labels.
microradiography.
mineralised sections.
at microscopic level.
finite element modeling.
implant markers
at macroscopic level.
natural markers.
comparative anatomy.
vital staining.
at both levels.
experimental approaches.

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CRANIOMETRY.
Involves measurements of skull
used to study the Neanderthal
and Cro-magnon skull.
give information of extinct
population and pattern of growth
Advantages: Precise measurements.
Disadvantages:All growth data must be cross sectional.

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ANTHROPOMETRY:
• measurements using soft tissue points overlying
bony landmarks in living individuals.
• can also be done on dried skulls but variation in
soft tissue thickness would produce different
results.
• Possible to follow the growth of an individual
directly.

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• CEPHALOMETRIC RADIOGRAPHY:
• allows direct measurement of bony skeletal
dimensions and follow up of the same individual
over time .
• Disadvantages
•:Depends upon precise orientation of head and precise
control of magnification.
• 2D representation of 3D structurewww.indiandentalacademy.com

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Mineralized sections.
• Fully mineralized sections are superior to
demineralized specimens as there is less processing
distortions and both organic and inorganic matrix can
be studied simultaneously.
• Cellular details and resolutions can be enhanced by
reducing the thickness of the sections.
• Specific stains can be used to enhance both cellular and
extra cellular details.
• Thin sections can however quench more rapidly

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Microradiography.
• High resolution of images of bone sections
• Differential density between primary and
secondary bone.
• Strength of the bone-proportional to degree of
mineralisation.
• secondary bone has more strength than primary
bone.
• Secondary mineralisation process takes about 8
months to form and hence the minimum retention
period after active orthodontic correction should
be 6-8 months.

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Fluorescent labels.
• Administered in vivo calcium binding labels
• anabolic time markers of bone formation.
• Mechanism of bone growth determined by
analysis of label incidence and interlabel distance.
• Sequential use of different colored labels assess
bone growth,healing and functional adaptation.
• Tetracycline,calcein green,xylenol orange,alizarin
complexone,demeclocycline and oxytetracycline
commonly used labels.

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Radioisotopes.
• Radioisotopes of certain elements or compounds
are often used as in vivo markers for studying
bone growth.
• Such labeled material is injected and after some
time located within the growing bone by means
of autoradiographic techniques.
• Commonly used markers are :
1. Technetium 99
2. Calcium 45
3. Potassium 32

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Autoradiography.
• Histological sections are coated with a nuclear track
emulsion to detect radiographic precursor for
structural and metabolic material.
• Specific radioactive labels for protein carbohydrates
or nucleic acids are injected.

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• Quantitative and qualitative assessment of the label uptake
is a physiologic index of cell activity.
• Commonly used autoradiographic labels are:
• A. 3 H thymidine.
• B. 3 H proline.
• C. Bromodeoxyuridine.

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Polarized light.
• indicates the orientation of collagen fibers within
the bone matrix.
• Most lamellar bone consists of collagen fibers
oriented at right angles.
• However 2 other configurations can also be
noted:longitudinally aligned(L osteons).

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• And mixed fiber pattern.(both L and A osteons).
• Loading condition at the time of bone formation
dictate the orientation of collagen fibers . Thus
bone formation can adapt to different loading
conditions by changing the internal lamellar
organization of bone tissue.

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Nuclear volume morphometry.
• cytomorphometric procedure to measures the
nuclear size for assessing the stages of
differentiation of osteoblastic precursor cells.
• Pre osteoblasts have significantly larger nuclei
than their precursors.
• used in determining the relative differentiation of
PDL and other bone living cells.

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Teleradiology.
 Introduced in 1982 at international
conference of PACS.
 Universal method of storing and
transporting digital images .
 Currently American college of radiology
have developed DICOM to allow the
transmisssion of images over the
internet.

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Vital staining
• reported by Belchier in 1796
• John Hunter- alizarin dye
• Alizarin reacts with calcium at sites of bone
calcification i.e. sites of active skeletal growth
thus marking these locations
• Other dyes : tetracyline
trypon blue
lead acetate
procion

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• Vital staining aids in studying:
Manner in which bone is laid down
site of bone growth
the direction and amount of growth
and the timing and relative duration
of growth at different sites.

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Natural markers.
• The persistence of certain developmental features
has led to their use as natural markers by means of
serial radiography.
• Eg: trabaculae,nutrient canals and lines of arrested
growth can be used for reference to study
deposition, resorption and remodeling.
• Certain natural markers are used as cephalometric
landmarks.

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Implant markers.
• Bjork devised a method of implanting tiny bits of
tantalum or biologically inert alloys into growing
bone which served as radiographic reference
markers for serial cephalometric study.
• The method allows precise orientation of serial
cephalograms and information on the amount and
sites of bone growth.

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Mechanism of growth
 3 mechanisms at the cellular level
 Hyperplasia
 Hypertrophy
 Secretion of extracellular matter

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Mechanism of growth in
soft tissues
 In soft tissues growth occurs by a combination of two
mechanisms namely:
 hyperplasia and hypertrophy
 These result in interstitial growth.

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Mechanism of growth in hard
tissues.
 The craniofascial skeleton grows by three
unique processes:
 Chondrogenesis: formation of cartilage
 Endochondral bone formation: process of
converting cartilage into bone
 Intramembranous bone formation: process
of bone formation from undifferentitaed
mesenchymal tissue.www.indiandentalacademy.com

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Comparison of physiologic
properties of bone and cartilage
 Characteristic cartilage bone
 Calcification Non calcified Calcified
 Vascularity Avascular Vascular
 Surface membrane Nonessential Essential
 Pressure resistance Tolerant Sensitive
 Rigidity Flexible Inflexible
 Modes of growth Interstitial Appositional
and appositional

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Endochondral bone formation
 Definition:It is the process of converting
cartilage into bone.
 Occurs in regions exposed to high levels of
compression
 In craniofacial region it is seen in areas like
 Synchondrosis at the cranial base
 Condylar cartilage
 Nasal septal cartilage

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Steps of chondrogenesis
 Chodroblasts produce matrix
 Cells become encased in matrix
 Chondrocytes enlarge,divide and
produce matrix
 Matrix remains uncalcified
 Membrane covers the surface but is not
essential

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Steps of endochondral bone
formation
 hypertrophy of chondrocytes and matrix
calcifies
 Invasion of blood vessels and
connective tissue cells.
 osteoblasts differentiate and produce
osteoid tissue.
 osteoblast tissue calcifies.

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Intramembranous bone
formation
Definition: it is the process of bone formation
from undifferentiated mesenchymal tissue
 Derived from neural crest cells
 Occurs in areas exposed to tension
 It differs from endochondral bone formation
by formation of bone directly from
mesenchymal tissue

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–Seen in areas like:
– Cranial vault
• Maxilla
• Mandible except condylar
cartilage

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Steps of intramembranous bone
formation
 Osteoblasts produce osteoid tissue.
 Cells and blood vessels are encased.
 Osteoid tissue is produced by
membrane cells.
 Osteoid calcifies.
 Essential membrane covers bone.

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Bone metabolism
• Bone is the primary calcium reservoir of the body
(99% stored in skeleton)
•Bone structure is sacrificed to maintain the critical
serum calcium levels at 10mg %

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Bone metabolism
Calcium homeostasis is supported by 3 mechanisms :
1. Rapid instantaneous flux of calcium from bonefluid (seconds) by
selective transfer of calcium ions into and out of bone fluid.
2. Shorterm control of serum calcium levels affects rates of bone
formation $ resorption
3. Longterm regulation of metabolism- have effects on skeleton
.

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TYPE OF BONES
 Lamellar bone
 Non lamellar bone
 Fine cancellous bone
 Coarse cancellous bone
 Woven bone
 Bundle bone
 Composite bone

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LAMELLAR BONE
 Comprises 99% of human skeleton
 Strong highly mineralised
 Mineralised in two stages:
 primary mineralisation
 secondary mineralisation

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Clinical significance
 Full strength of lamellar bone supporting
an orthodontically moved tooth is not
attained for upto a year after completion
of active treatment.

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Non Lamellar bone
 Makes up fine cancellous bone tissue
 No distinct stratification in fibre
orientation

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Woven bone
 Type of non lamellar bone
 Weak , disorganised, poorly mineralised
 Not found in adult human skeleton
under normal conditions
 First bone formed in response to
orthodontic loading.

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Bundle bone
 Present adjacent to periodontal
ligament
 Presence of perpendicular striations
called sharpey‘s fibres.
 Formed on depository side of
socket, laid dowm in the direction
toward the moving tooth root.

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Composite bone
 Predominant bone type during early
retention phase
 Most rapid means of producing strong
bone
 Formed by deposition of lamellar bone
within a woven bone lattice.

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Fine cancellous bone tissue
 Formed by periosteum and endosteum
 Marrow spaces are fine
 It is located in cortex e.g. posterior
border of a growing ramus in a child
 Fastest growing of all bone types

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Coarse cancellous bone
 Produced by endosteum only
 Irregular marrow spaces containing red
or yellow marrow
 Irregularly arranged trabeculae
 Present in medulla

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Mechanisms of bone growth
 Deposition and resorption
 Growth fields
 Modelling
 Remodelling
 Growth movements
drift
displacement

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Deposition and resorption
 Bone sides which face
the direction of growth
are subject to
deposition (+) and
those opposite to it
undergo
resorption(-)
…surface principal

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Deposition and resorption
 Bone produced by
covering membrane-
periosteal bone
comprises about half
of the cortical bone
tissue: bone laid down
by the lining
membrane-endosteal
bone makes up the
other half.

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Enlow‘s V principal
 Most useful and basic
concept in facial
growth as many facial
and cranial bones have
a V- shaped
configuration.
 Bone deposition(+)
occurs on the inner
side and resorption (-)
occurs on the outer
surface.

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Transverse histologic section of bone:
A.Periosteal surface reorptive,endosteal
surface depository.
B.New endosteal bone addedon inner
surface.
C.Endosteal layer produced covered by
periosteal layer following outward
reversal.
D.Cortex made entirely of periosteal
bone….outer surface depository and
inner surface resorptive.

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Example with V oriented vertically
 When bone added
on lingual side of
coronoid
process,growth
proceeds and this
part of the ramus
increases in
vertical dimension.

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Example of V oriented horizontally
 Same deposits of
bone also bring
about a posterior
direction of growth
movement.
 This produces a
backward
movement of
coronoid processes
even though deposit
is on the lingual
side.

107www.indiandentalacademy.com

108
 Same deposits carry
base of bone in medial
direction as in fig 1.
 Hence, the wider part
undergoes relocation
into a more narrow part
as the whole v moves
towards the wide part
(fig 2)

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Growth fields
 Inside and outside of
every bone is
covered by growth
fields which control
the bone growth.
 They are both
resorptive and
depository types..

110
 About one half of the
bone is periosteal and
the other half
endosteal.If endosteal
surface is resorptive
then periosteal surface
would be depository.
 Provides two growth
functions:
Enlargement of any
given bone
Remodelling of any
given bone

111
Growth sites
 Growth fields having
special role in the
growth of the particular
bone are called growth
sites
 e.g. mandibular
condyle, maxillary
tuberosity, synchondros
is of the
basicranium, sutures
and the alveolar
process.

112
Growth sites
 Such special
sites do not out
the entire carry
growth process
but the entire
bone takes part

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Growth centers
 Special areas which are
believed to control the
overall growth of the
bone e.g.mandibular
condyle.
 Force, energy or motor
for a bone resides
primarily within its
growth centre.
 Now believed that these
centers do not control
the whole growth
process.

114
MODELING
 Bone modeling involves
independent sites of resorption
and formation that change the
size and shape of a bone.

115
CONTROL FACTORS FOR
BONE MODELING
– Mechanical Peak
load in Micro strain.
1. Disuse atrophy <200.
2. Bone Maintenance 200—
2500.
3. Physiological Hypertrophy 2500—
4000.
4. Pathological Overload >4000.
•

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• Endocrine.
1. Bone metabolic hormones-PTH,Vit D,Calcitonin.
2. Growth Hormones-Somatotropin,IGF 1,IGF 2.
3. Sex steroids-Testosterone,Estrogen.

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Remodelling
 Required differential growth activity required for bone
shaping.
 It involves deposition and resorption occuring on
opposite ends
 Four types
 Biochemical remodelling
 Haversian remodelling
 Pathologic remodelling
 Growth remodelling

118
 E.g. The ramus moves
posteriorly by the
combination of
deposition and
resorption.
 so the anterior part of
the ramus gets
remodeled into a new
addition for the
mandibular corpus.

119
Functions of Remodeling
1. Progressively change the size of whole bone
2. Sequentially relocate each component of the
whole bone
3. Progressively change the shape of the bone
to accommodate its various functions

120
1. Progressively change
the size of whole bone
2. Sequentially relocate
each component of
the whole bone
3. Progressively change
the shape of the bone
to accommodate its
various functions
Functions of Remodeling

121
4. Progressive fine tune fitting of all the
separate bones to each other and to their
contiguous ,growing, functioning soft tissues
5. Carry out continuous structural adjustments
to adapt to the intrinsic and extrinsic
changes in conditions .

122
Drift
 It is remodeling process
and a combination of
deposition and
resorption.
 If an implant is placed
on depository side it
gets
embedded.eventually
marker becomes
translocated from one
side of cortex to other.

123
Displacement
 Displacement is a physical movement of
the whole bone as it remodels
 Two types:
primary displacement
secondary displacement

124
Primary displacement
 It is a physical
movement of a
whole bone and
occurs while the
bone grows and
remodels by
resorption
deposition
 E.g. in maxilla

125
Secondary displacement
 It is the movement
of a whole bone
caused by the
separate
enlargement of
other bones

126
Combination of remodeling &
displacement
 Both these mechanisms carries out two
general functions
 Positions each bone
 Designs and constructs each bone

127
Rotation
 According to
Enlow, growth rotation
is due to diagonally
placed areas of
deposition and
resorption
 Two types
 Remodelling rotations
 Displacement rotations

128
Principle of ‗Area relocation‘
Both remodeling and
displacement together
cause a shift in existing
position of a particular
structures with reference
to
another
.

129
Counter part principle
 ―Growth of any given
facial or cranial part
relates specifically to
other structural and
geometric
counterparts in the
face and cranium‖ -
Enlow

130
Growth equivalent principle
This principle proposed by Hunter & Enlow
relates the effects of cranial base growth on
the facial bone Growth.

131www.indiandentalacademy.com

132
REFERENCES:
 Proffit:contemporary orthodontics.
 Moyers:handbook of orthodontics.
 An inventory of United states and
Canadian growth record sets.S.Hunter
, Baumrind S AJO 1993.
 Craniofacial imaging in orthodontics :S
Kapila et al AO 1999:69
 Essays in honour of Robert moyers
CFGS.monograph 24.

133
References
 Bone biodynamics in orthodontics:CFGS.27
 Atlas of craniofacial growth in Americans of
African descent CFGS.26
 Growth changes in the nasal profile from 7-8
yrs AJO 1988:94 Meng H ,R Nanda
 Longitudinal changes in 3 normal facial types
.S Bishara,AJO1985:88
 S Bishara,J R Peterson, changes in the facial
dimensions & relationships between the ages
5-25yrs.AJO 1984:85

134
References
 Lewis A B, Roche AF pubertal spurts in
cranial base & mandible AJO 1985:55
 Popovich.Thompson. Craniofacial templates
for orthodontic case analysis.
 Baumrind S,Korn EL,quantitation of maxillary
remodeling. AJO 1987:91
 Atlas of craniofacial growth CFGS monograph
2.
 Moyers,Van Der Linden standards of human
occlusal development CFGS:5
 B Grayson 3D cephalogram theory,technique
and clinical application.

www.indiandentalacademy.com 135
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