Growth Pattern Variability (Concepts of Growth & Development) - Orthodontics
10,705 views
22 slides
Mar 10, 2017
Slide 1 of 22
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
About This Presentation
This Presentation describes the Topic of Pattern, Variability & Timing of Growth from 2nd Chapter of Contemporary Orthodontics by Proffit.
Size: 392.16 KB
Language: en
Added: Mar 10, 2017
Slides: 22 pages
Slide Content
PATTERN,
VARIABILITY& TIMING
OF GROWTH
Concepts of Growth & Development
SARANG SURESH HOTCHANDANI
SARANG SURESH HOTCHANDANI
Concepts of Growth & Development
•The term growth usually refers to an increase in size or number.
•The term development refer to an increase in complexity.
•It is increase in specialization with loss of potential.
•Growth is largely an anatomic phenomenon.
•Development is physiologic and behavioral.
SARANG SURESH HOTCHANDANI
Growth Pattern
•It is set of complex proportional relationships at a point in
time and the also the changes in these proportional
relationships over time.
•In other words, Arrangement of body at any one time is a
Pattern of Spatially Proportioned Parts.(1st Part of Definition)
•Changes in these Spatial Proportional Parts of Body is called
pattern of growth (2nd Part of Definition).
SARANG SURESH HOTCHANDANI
Cephalocaudal Gradient of Growth
•It refers to Growth of Body
extending from head towards
feet.
•means pehlejo head (cephalo) kenear structures honge
wo grow karengethen aahisteaahistegrowth outward
hotijayegi.
SARANG SURESH HOTCHANDANI
Cephalocaudal Gradient of Growth
•During prenatal growth, from conception to 5 months, the head grows more than the body.
•In humans, the head comprises almost 50% of total body length at approximately the 3rd
month of intrauterine development.
•At this stage Cranium is Large relative to Face
•By the time of birth the head has decreased to approximately 30% of total body length as a
result of the limbs and trunk growing faster than the head.
•At birth, legs represent about 1/3rd of total body length while in adult they represent half of
total body length.
SARANG SURESH HOTCHANDANI
Cephalocaudal
Gradient of Growth
•So here, pattern of growth is progressive
decrease in head and face.
•This trend continues postnatally along
an axis of increased growth from the
head to the feet.
•Finally, in adults, the head represents
approximately 12% of the body length.
•There is more growth of lower limbs
than upper limbs in post-natal life
Schematic representation of the changes in overall body proportions
during normal growth and development. After the third month of fetal
life, the proportion of total body size contributed by the head and face
steadily declines. (Redrawn from Robbins WJ, et al. Growth. New
Haven: Yale University Press; 1928.)
SARANG SURESH HOTCHANDANI
Differential Growth
Not all the tissues systems of body
grow at the same rate because they
are present in different various parts
of body and that’s why their growth
depends on growth of that part of
body…
SARANG SURESH HOTCHANDANI
Scammon’s Curve
•Graphic representation for
Differential growth which tells us that
each tissue grows at different rate.
•Growth of the neural tissues is nearly
complete by 6 or 7 years of age.
•Growth of general body tissues which
include muscles, bones & viscera
show “S shaped curve” have slow rate
of growth during childhood and
accelerated rate of growth during
puberty.
SARANG SURESH HOTCHANDANI
Pattern of Facial Growth
•As in general body, cephalo-caudal growth gradient is
also present in Head.
•At birth, the face and jaws are relatively underdeveloped
compared with their extent in the adult. As a result,
there is much more growth of facial than cranial
structures postnatally.
SARANG SURESH HOTCHANDANI
Predictability
•it means Repetition
•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.
SARANG SURESH HOTCHANDANI
Pattern Also Repeat
•just like apjaanteho harinsankejo bones hainsimilar
tareekese grow karengemeans agar apme maxilla ke
baaadee mandible developeor grow ho rahahaijeseham
ooperparhkeaayehain… weseee aappredict (means
anooman) kersaktihainkedusreperson me b same
tareekese ee hogameans kemandible maxilla kebaad
develop hogi. to is concept kopredictability kehtehain
means jo Pattern haingrowth and development kewo
predict kiyeja saktehain.
SARANG SURESH HOTCHANDANI
VARIABILITY
SARANG SURESH HOTCHANDANI
Variability
•Generally speaking variability in biology is
defined as deviation from normal pattern of
growth.
•clinically we should able to decide, whether
individual is at the extreme end of normal
variation or he/she falls outside the normal
range before saying he/ she has abnormal
growth.
SARANG SURESH HOTCHANDANI
Variability
•Rather than saying growth is normal or abnormal, we should
think in terms of deviation from the usual pattern and express this
variability (deviation from usual pattern) quantitatively on growth
chart.
•In this chart child is evaluated relative to its peers.
•Normal variability is derived from large scale studies of groups
of children and is shown by solid line on graph for comparing.
•If the individual falls along the 50% of peers he/she will be at the mid of
line.
•If he/she falls along 90% of peers, he/she will be at the 90% line.
SARANG SURESH HOTCHANDANI
Variability
•It means child is at extremes of normal position if he/she is at least
above 97% of peers.
•If he/she falls along less than 90% of peers, he/she will be at
10% of line.
•So, for this reason, child’s growth should plot along
same percentage line at all ages to evaluate that child
over time.
•If the percentage position line of that person is changed, we
should suspect some growth abnormality has occurred.
SARANG SURESH HOTCHANDANI
TIMING
SARANG SURESH HOTCHANDANI
Timing
•Variability in growth occurs in many
ways as under;
•From normal variation
•Influences outside normal experience
(serious illness)
•Timing
SARANG SURESH HOTCHANDANI
Timing
•As we see in our surroundings that same event of
growth happens for different persons at different
time.
•Some children grow and develop rapidly and mature
early while some children grow & develop slowly and
mature late
•So, this occurs because biological clocks of
different persons are set differently.
SARANG SURESH HOTCHANDANI
Timing
•Variation in growth and development occurring
because of timing are mostly seen in adolescence.
•All children undergo spurt of growth at adolescence but
spurt of growth occurs at different times in different
individuals.
•Spurt of growth; rapid rise in height & weight.
SARANG SURESH HOTCHANDANI
Timing
•In girls, onset of menstruation is excellent indicator of arrival
of sexual maturity accompanied by spurt of growth.
•Earlier the adolescence growth spurt occur the more intense
appears to be.
•Agar 2 baaraahinjarahikreme growth spurt sawerthyoaa be
bekhan then jahinme sawergrowth spurt thyoaa oohobaar
drighotheendoas compared to be je.
SARANG SURESH HOTCHANDANI
Timing
•There are 2 methods of age measurement
•Chronological age
•Amount of time since birth or conception.
•Biological age or developmental age
•Gaining of various developmental markers or stages.
•Timing variability can be decreased by using biological age.
•Pattern is expressed at different time chronologically but not at
different times physiologically.
SARANG SURESH HOTCHANDANI
THE END
Source: Contemporary Orthodontics (Proffit)
Email: [email protected]
Twitter: www.twitter.com/fetusdentista
Final Year BDS @ Bibi Aseefa Dental College, SMBBMU, Larkana, Sindh, Pakistan.
SARANG SURESH HOTCHANDANI