Growth & development

CONTENTS
Introduction
Definitions
Differences between growth and development
Phases of growth and development
Prenatal period
Postnatal period
Theories of growth
Factors affecting physical growth
Growth assessment Methods
Milestones of growth and development
Clinical implications
Conclusion
References

INTRODUCTION
 Human development is a continuous process that begins when an
oocyte(ovum) from a female is fertilized by a sperm(spermatozoon)
from a male.
 Development involves many changes that transform a single cell, the
zygote(fertilized ovum), into a multicellular human being.
 Most development changes occur before birth, but important changes
also occur during the later periods of development; infancy,childhood,
adolescence, and adulthood.

 Growth is a fundamental attribute of developing organisms.
The dramatic increase in size that characterizes the living
embryo is a consequence of :
1) Increased number of cells resulting from mitotic divisions
(hyperplasia)
2)Increased size of individual cells (hypertrophy)
3)Increased amount of non-cellular material (accretion).

 Growth may be
o Interstitial –
 where increase in bulk occurs within a tissue or organ
 seen in soft tissues.
o Appositional –
• where surface deposition of tissue enlarges its size
• Seen in hard tissues (bone,dental tissues).
• MATURATION is a counterpart of growth.It initiates not only
the attainment of adult size & proportion but also the full adult
constituent of tissues(eg:-mineralization) & the complete
capability for performance of each organ’s destined functions.

DEFINITIONS -GROWTH
 Stewart,1982-Growth may be defined as developmental increase in
mass
 Profitt,1982- Increase in size and number
 Moyer,1988- Normal changes in the amount of living substance.
 J.S.Huxley-Self multiplication of a living substance
 Krogmann- Increase in size,proportion &progressive complexities
 Moss- change in any morphological parameter & is measurable.

DEFINITIONS-DEVELOPMENT
 Todd- Development is progress towards maturity
 Moyers- Development refers to all the changes that occur naturally &
unidirectional in life of an individual from its existence as a single cell
to its elaboration as a multifunctional unity terminating in death
 Pinkham – progressive evolution of a tissue.
 J.H.Salsamann- It relates to cell division,growth,differentiation and
maturity.

DIFFERENCES BETWEEN
GROWTH AND
DEVELOPMENT.

PHASES OF GROWTH AND
DEVELOPMENT

PHASES OF GROWTHANDDEVELOPMENT
 PRENATAL PERIOD(0 – 40 weeks)
 PERIOD OF OVUM ( 0 – 1 week)
 PERIOD OF EMBRYO ( 1- 8week)
 PERIOD OF FETUS ( 8 – 40 weeks)
 POSTNATAL PERIOD
 NEONATAL PERIOD
 PRESCHOOL PERIOD
 SCHOOL PERIOD
 PUBERTY & ADOLESCENCE

PRENATAL PERIOD
 The total period of prenatal life consists of 40 weeks and after
28 weeks the fetus is considered viable.
 The period of intrauterine life can be divided into 2 principle
developing organs:
 The embryo
 The fetus

1-2 WEEK •Bilaminar disc formation
•Amniotic cavity and yolk sac
are formed and are seperated
by embryonic disc
•Prechordal plate is formed
indicating the future cranial
region and the primitive
mouth.

3rd
WEEK
•Trilaminar disc is formed.
•Primitive streak initiates the
formation of embryo.
•Notochord is formed.
•Primitive endothelial cells are
formed which fuse into the primitive
heart tube.
•Cardiovascular system is the first to
reach its functional stage.
•Head forms half of the body length.

4th
WEEK
•Neural tube is formed
•Head,tail and lateral folds form
•C shaped embryonic disc
•Major organs systems start
developing
•Foregut,midgut,hindgut are
formed
•24th day-3 pairs of branchial
arches
•Dental lamina is formed
•27th day-upper limb buds
appear
•Crown rump length is 4-5mm

5TH
WEEK
•4 branchial arches present
•Upper limbs differentiate
into hand plates
•Otic placodes &optic
vescicles are seen
•Heart beat can be detected
ultrasonographically
•End of 5th week-42-44 pairs
of somites are formed
•Lower limb buds appear

6th
WEEK
•Formation of primitive nose ,
philtrum & palate
•Retinal pigment in the eye
•Increase in head size which is
more bent over the heart
prominence
•Reflex response to touch
•Tooth buds of primary teeth
•Cranium to face ratio 40:1
•Crown rump length – 21-
23mm

7th
WEEK
•Eyelid formation begins
•Midgut herniation occurs
•Change of blood supply
to the face from internal
carotid artery to external
carotid artery(critical
period)

8th
WEEK
BEGINNING
•Hands-short and webbed
•Eyes –open
•Tail-present but stubby
•Scalp vascular plexuses occur as band
around the head
BY THE END
•Tail disappears
•Eyes-unite by epithelial fusion
•Ovaries & testes are formed but external
genitalia are not yet distinguishable
•Slight purposeful limb movements occur
but are not felt by the mother.

9th WEEK
(PERIOD OF
FETUS)
•Crown rump length – 3cm
&weight – 8gm
•Period of rapid proliferation and
differentiation
10th WEEK •External genitalia become
distinguishable

12th WEEK
•Erythropoiesis –decreases in liver
and begins in spleen
•By the end - Primary ossification
centre appear in skeleton,
especially in skull and long bones.

13th - 15th
WEEK
•Breathing and swallowing motions
appear
•Crown calcification of primary
incisors and first molar begins
•Condyle , coronoid and the angle of
mandible become distinct

17th – 20th
WEEK
•Primordial follicles form oogonia
in the ovaries
•Brown fat is formed which
generates heat for the infant
•SUCKING REFLEX develops
•Calcification of canines and 2nd
molars
•Myelination of nerve begins.

20th WEEK
•Lanugo hair develops
•Skin is coated with vernix caseosa
24th WEEK
•Secretory epithelial cells secrete
surfactant in the lungs
•Histodifferentiation of enamel organ
& dental lamina forms ameloblasts &
odontoblasts
•Second trimester ends
•Safe for dental treatment for the
mother

25th WEEK
•3RD TRIMESTER BEGINS
•Weight-900gm
•Length – 25cm
28th WEEK •Eyes begin to reopen
•GRASP RELEX well developed
•Fetal head turns down
•Weight – 1000-1300gms
•Length – 35cm
30th
WEEK
•Fetus appears reddish & wizened
since skin is thin & there is relative
abscence of subcutaneous fat

36th – 40th
WEEKS
•Fat develops rapidly resulting in a
red,smooth,plump appearance
•This period is devoted mainly to
building up of tissues& to preparing
systems involved in the transition from
intrauterine to extrauterine environment
primarily the respiratory & the CVS
•Hand forms 1/3rd of the body length
•Cranium to face ratio is 8:1
•Length is 45-50cm(30 inches)
•Weight is 3200gm or 2.5 - 4.5 kg
•Head circumference 35 cm

CLINICAL APPLICATION OF
PRENATAL DEVELOPMENT

MATERNAL AGE
Maternal age and risk of labor and delivery complications
Patricia A. Cavazos-Rehg et al;
•OBJECTIVE :
To examine associations between maternal age and
prevalence of maternal morbidity during complications
of labor and delivery.

•RESULTS:
In analyses that controlled for demographics and clinical
confounders, they found that complications with the highest odds
among women, 11–18 years of age, compared to 25–29 year old
women, included preterm delivery, chorioamnionitis, endometritis,
and mild preeclampsia.
Pregnant women who were 15–19 years old had greater odds for
severe preeclampsia, eclampsia, postpartum hemorrhage, poor fetal
growth, and fetal distress.
Pregnant women who were ≥35 years old had greater odds for
preterm delivery, hypertension, superimposed preeclampsia, severe
preeclampsia, and decreased risk for chorioamnionitis.
Older women (≥40 years old) had increased odds for mild
preeclampsia, fetal distress, and poor fetal growth.

EFFECTS OF VARIOUS DRUGS ON
PRENATAL DEVELOPMENT
•Some of the major factors currently posing a threat to
bearing a healthy child include exposure to chemicals and
radiation at home or work, exposure to infectious diseases,
and use of cigarettes and other drugs during pregnancy.
.

1.Alcohol
 Fetal alcohol spectrum disorders (FASDs) are a collection of conditions
that may develop in a baby whose mother consumed alcohol during
pregnancy.
Some consequences of FASD include the following:
Facial
disorders like
cleft lip
&palate
Stunted growth
Behavioural disorders
Poor attention or hyperactivity
Underdeveloped
head

2.Amphetamine (Adderall) :
• Females who are managing attention deficit
hyperactivity disorder (ADHD) often use the
brand name drug called Adderall to treat their
symptoms.
• The drug increases dopamine and norepinephrine
levels in the brain which allow for better focus
and impulse control.
• Considering the potential harm to females and
developing babies, studies are mostly limited or
report negative side effects in using Adderall
during pregnancy

CHLORAMPHENICOL
Breakdown of red cells
Gray baby syndrome
STREPTOMYCIN
KANAMYCIN –
Damages eight
nerve
deafness
NITROFURANTOIN
affects the glutathione
reductase activity
Hemolytic anemia

SULFASALAZINE
jaundice
TETRACYCLINE
•Chelates the calcium salts and so is
incoporated in bones and teeth and
causes hypomineralization of
enamel
Slowed bone growth
Increased susceptibility
to cavities
Permanent discoloration of teeth

4.Antidepressants :
•One type or antidepressant, selective serotonin reuptake inhibitors
(SSRIs) are generally acceptable for use and include citalopram
(Celexa), fluoxetine (Prozac), and sertraline (Zoloft).
• Paroxetine (Paxil) however, another SSRI, is strongly discouraged
due to a possible link with fetal heart defects and ASD

6.Corticosteroids (Steroids)
•The risks associated with corticosteroids
are mitigated when use is limited to a single
injection.
•Side effects only tend to occur if steroids
were introduced at very high doses or early
in the pregnancy.

IMPACT OF MATERNAL STRESS ON
INFANT HEALTH

Psychosocial Stress during First Pregnancy Predicts
Infant Health Outcomes in the First Postnatal Year
A. L. Phelan
•Objective
To evaluate the impact of psychosocial stress during pregnancy on
infant health outcomes in the first postnatal year.

•Results
Women who were younger, minority, unmarried, publicly insured and
without a college degree were more likely to report high levels of prenatal
stress.
High prenatal stress was a significant predictor of maternal reporting of
gastrointestinal illness (p<0.0001), respiratory illness (p=0.025), and total
illness in the first year (p< 0.0001).
 High prenatal stress was also a significant predictor of urgent care visits (p<
0.0001) and emergency department visits (p= 0.001).

GENERAL POSTNATAL CHANGES IN
DIMENSIONS
& PROPORTIONS

GENERALPOSTNATAL CHANGES IN DIMENSIONS&
PROPORTIONS
NEONATAL
SKELETON –
• Bones-290(adult-206)
•Calvaria : facial – 8:1 (adult-
2.5:1)
•Skull bones -45(adult – 22)

NEONATAL SKELETON
•FRONTAL
BONE at birth
is in 2 halves
which fuses at
2 years
•PARIETAL
BONES – 2
•OCCIPITAL
BONES at birth
has 4 pieces
which fuse by 3-
4 yrs of life
•SPHENOID BONE –
3 parts(body , lesser &
greater wings) which
fuses during the 1st year
•Sinuses donot develop
in the sphenoid until 5th
year

NEONATAL
SKELETON
•Ethmoid bone – at birth is
in 3 pieces (median plate ,
right & left labyrinth) which
fuse by the 5th & 6 th year
of life
•Temporal bone
consists of 4 parts
which completely fuse
by puberty

CHANGES IN BODY PROPORTIONS
•The body proportions are a result of the differential rates of growth
of the cephalic and caudal ends
•Massive changes in the body proportion occur the fetal life to
adulthood
•MIDPOINT–
o 2 mnths embryo – close to chin
o at birth – just above umbilicus
o in adult – pubic symphysis
•LENGTH OF THE HEAD–
o at birth – 22 % of body area
o at 12 years – 13% of body area
o in adult – 10% of body area

CHANGES IN POSTURE
•The newborn is usually kept at
supine position but can be literally
folded to its most comfortable posture
i.e; the posture simulating the fetal
posture of partial flexion
•Mild lordosis & protruberance of the
abdomen is a common finding at 2-3
years of age but this disappears by 4
years

CHANGES IN NECK
•AT BIRTH – Relatively short and
musculature is not developed
•Functional development of these
muscles begins from 2 months onwards

CHANGES IN CHEST
GIRTH OF THE CHEST –
at birth – smaller than head
circumference
 at 2 years - equal to head
circumference
 at 15 years – 3:2 ratio
 in adults – 5:3

CHANGES IN ABDOMEN
•UMBILICUS
• SHEDS OFF around 12th to 15th day
•Protruberant but soft
•Until 2 yrs – equal to chest
•After 2 yrs – less than the chest

CHANGES IN EXTREEMITIES
•AT BIRTH – legs are short & arms are long
•ARMS –
 birth to 2 yrs - length increases by 6.75%
 8 years – 50% length
 16- 18 years – slow growth
•LEGS –
birth – short & curved
 2years – length increases to 40%
 6 years – straight
 8 years – 50% longer
• early maturer – shorter legs than the late maturer

CHANGES IN CRANIOFACIAL SKELETON
•3rd month to birth – longer and wider in relation to height
• at birth – 30 – 60% of total growth
•4 years – growth is almost completed
•4 years onwards – increases in all dimensions
•HEAD:-
ATBIRTH – 35 CMS
6 MONTHS – 44 cms
1 YEAR – 4 inches increase takes place
10 YEARS – 95% of total head growth completes

FONTANELLES:-
AT BIRTH – CLOSURE TIME
• anterior fontanelle 18 – 24 months
• posterior fontanelle 2 months
• Sphenoid fontanelle 6 months
• Mastoid fontanelle 6-18months

CRANIAL SYNCHONDROSES :-
•SPHENOOCCIPITAL 24 – 35 years
•SPHENO ETHMOIDAL 2-4 years
•MID SPHENOID shortly after birth

 SUTURES OF CRANIUM :
•CORONAL SUTURE 24 – 35 years
•SAGGITAL SUTURE 22-30 years
•LAMBDOID SUTURE closure starts at 29 years
•SQUAMOUS SUTURE closes later in life
CLOSURE TIME

FACE :-
•AT BIRTH – lower and middle 3rd underdeveloped
•ONSET OF PUBERTY – forehead flattens & widens ,lips
thicker& face acquires an oval shape

NASO MAXILLARY
COMPLEX:-
•In 6th fetal week maxilla develops in
membranous tissue
•The maxilla proper is a result of highly
complex growth pattern with many
different components

•Maxilla is attached to neurocranium directly with fronto maxillary
sutures and indirectly by means of various other suture like the
nasal , the lacrimal , the ethmoidal, the nasal septum including the
vomer , the palatine bone & zygomatic arch(edge – edge
atatchment)
•During the early period the saggital interrelationship of jaw is
characterized by mandibular protrusion which is gradually reversed
NASO MAXILLARY COMPLEX:-

•At birth , maxilla is placed more anteriorly giving a
class II relationship to the jaws
•Later in course of postnatal development both maxilla
and mandible with their associated soft tissues grow
forward & downward and establish a normal class I
relationship

•MAXILLARY SINUSES at birth are not developed and are
present as slits
•Development of orbital cavities is practically complete at birth
•Nasal cavity is located between the 2 orbits of the eyes and its
floor is roughly at level with their bottoms
•The alveolar process can only be faintly discerned & the palate has
a weak transversal curvature
•The maxillary body is almost entirely fixed with the developing
teeth

MANDIBLE:
Although still seperated by a symphysis in the midline the 2 halves of the
mandible fuse into a single bone by the age of 1-2 years
AT BIRTH –
•The 2 rami are present
•Condylar development is minimal
•A thin line of fibrocartilage & connective tissue exists at the midline of
the symphysis to separate the right &left mandibular bodies

MANDIBLE:
•The symphysial cartilage is replaced by bone (between 4 months of
age & the end of 1 year)
•Growth is quite general with all surfaces showing bone apposition ,
especially at the alveolar border , distal & superior surfaces of ramus
, condyle , lower border & lateral surface of mandible.
•The structure of alveolar process & the muscles are poorly
developed at this age , so that , its basal arch mainly determines the
shape of the mandible in neonate.

Variations in bone density across the body of the immature
human mandible
Erin F. Hutchinson,Mauro Farella ,Jakobus Hoffman,Beverley Kramer
•The aim of this study was thus to evaluate changes in bone
mineral density across the body of the immature human mandible
during the early stages of dental development
•The study sample included 45 human mandibles, subdivided into three
age groups: prenatal (30 gestational weeks to birth; n = 15); early
postnatal (birth to 12 months; n = 18); and late postnatal (1–5 years; n =
12). Mandibles were scanned using X‐ray micro‐computed tomography.
• Eight landmarks were selected along the buccal/labial and lingual
surfaces of each dental crypt for evaluation of the bone mineral density
•Bone mineral density values were calculated using a reference standard
and analysed using multivariate statistics.

•The bone mineral density of the lingual surface was found to be
significantly higher (P ≤ 0.000) than that of the buccal/labial surface.
•Furthermore, bone mineral density in the alveolar region of the
buccal/labial surface of the deciduous central incisor (P ≤ 0.001), the
deciduous first molar (P ≤ 0.013) and lingual alveolar area of the
deciduous second molar (P ≤ 0.032) were significantly greater in the early
postnatal period than in the prenatal period.
•While changes in bone mineral density across the lingual surface were
consistent with the progression of development and the biomechanical
demand of the tongue , changes observed across the buccal/labial surface
of the mandible appeared to accompany the advancing dental
development.
•Thus, changes in bone mineral density across the mandible appear to be
reflective of the stage of dental development and the level of
biomechanical loading.

TEMPOROMANDIBULAR
JOINT:-
•3 phases of development are seen in the intrauterine period
1. Blastemic stage ( 7-8 weeks)
2. Cavitation stage (9-11 weeks )
3. Maturation stage (after 12 weeks )
POSTNATAL CHANGES:
• At birth – articular disc is flat & develops as accentuated S
shaped profile as the articular tubercle develops
• Condylar cartilage is about 1.5 mm thick at birth but soon thins
down to about 0.5 mm .by 20-30 years it is completely replaced
by endochondral ossification
• Mandibular condyle grows in a constant posterior , superior
&lateral direction and attains a mature contour by late mixed

GUM PADS :-
•The edentulous arches of a child vary from an edentulous adult
•The alveolar arches of an infant are called gumpads which are firm
& pink structures with a definite form
•Each gumpad is divided into 10 segments by transverse grooves.
The grooves between the deciduous canine and 1st molar segments
are prominent and called the lateral sulci

GUM PADS :-
UPPER GUM PAD:
•GINGIVAL GROOVE – seperating
gumpad from palate
•DENTAL GROOVE – originates in
the incisive papilla region and extends
backwards to touch the gingival
groove in the canine region & then
laterally to end in the molar region.
•LATERAL SULCUS – it is a
deepened groove seperating the canine
and deciduous 1st molar segments.

GUM PADS :-
LOWER GUMPAD:
•U shaped everted antero-posteriorly
•Gingival groove – demarcates the
lingual extent of the gumpads
•Dental groove – running from
mandible backwards laterally to join
the gingival groove in the canine region
•Lateral sulcus – seperating canine and
deciduous 1st molar segments

RELATIONSHIP OF GUMPADS:
•At rest – gumpads are seperated by the tongue lying over the lower
gumpad
•There is no definite anteroposterior relationship of the gumpads on
occlusion but the lower gumpads being smaller the lateral sulcus of
the lower gumpad lies distal to that of the upper
•There is a variable overjet with contact only in the 1st molar segments

TONGUE :-
•Comparatively large in relation to
small mouth
•The tongue is flat , thin & blunt tipped
probably due to the short frenum
•The tongue at this stage performs only
one function i.e; acts as a piston while
suckling

LIPS:-
The lips of a newborn are reddish pink , soft & supple
The middle of upperlip has a small projection , the labial tubercle, which
is said to disappear after the sessation of suckling.

•It is the child’s reserve of energy.
•It is nothing but the cheek prominences giving the
infant a chubby cheek appearance.
•It is formed of a firm encapsulated mass of fat lying
between the subcutaneous fat and the muscles of
cheek
•Its exact role in suckling is not known.
•It probably plays no role in suckling but it has been
found to regress once the suckling has ceased.
BUCCAL PAD OF FAT(CORPUS
ADIPOSUM/BICHAT’S FAT PAD)

PRIMITIVE OR PERSISTENT REFLEXES
•The normal emergence and inhibition of primitive reflexes is
extremely important in neonates.
• However, these reflexes should disappear and allow for
voluntary skills to replace them.
• Those children who exhibit abnormal reflex patterns most
likely suffer from a neurological problem which can result in.. –
dysphagia, – delayed speech – reading problems
• The reemergence of primitive reflexes in adults with a
formally mature and healthy neurological system can indicate a
problem in the central and/or peripheral nervous systems.

Babinski reflex
When the Babinski reflex is present in a child older
than 2 years or in an adult, it is often a sign of a central
nervous system disorder.
The central nervous system includes the brain and
spinal cord. Disorders may include:
Amyotrophic lateral sclerosis (Lou Gehrig disease)
Brain tumor or injury
Meningitis(infection of the membranes covering the
brain and spinal cord)
Multiple sclerosis
Spinal cord injury, defect, or tumor
Stroke

GRASP REFLEX:
•If Palmar grasp reflex persists
beyond 2 to 4 months, it delays or
affects functions like grasping a rattle,
releasing objects from hand and also
hand manipulation skills.
•Palmar grasp reflex may be a sign
of anterior cerebral artery
syndrome in adults

MORO REFLEX
•Persistence of the Moro response beyond 4 or 5
months of age is noted only in infants with severe
neurological defects.
•Absence or asymmetry of either abduction or
adduction is abnormal, as is persistence of the
reflex in older infants, children and adults.
• Absence indicates a profound disorder of
the motor system or a generalised disturbance of the
central nervous system.
•An absent or inadequate Moro response on one
side is found in infants with hemiplegia, brachial
plexus palsy, or a fractured clavicle.

Stepping Reflex retention may lead to:
•Toe walking – ‘running like an ostrich’
•Tight calf muscles
•Poor balance and muscle control
•Feet and ankle problems with pain and
dysfunction
•Recurring hamstring injuries and mid-
low back strains
•Visual problems due to an altered
perception of the horizon – head tilts
forward and eyes look upward
STEPPING REFLEX

SUCKING REFLEX :
Retained Juvenile Suck Reflex may
lead to:
•Speech and articulation problems
•Difficulty swallowing and chewing
•Difficulty speaking and doing manual
tasks at the same time
•Involuntary tongue or mouth
movements when writing or drawing
•Class II dental occlusion requiring
dental intervention

TONIC NECK REFLEX :
TNR retention may lead to:
•Hand-eye co-ordination difficulty
•Awkward pencil grip
•Difficulty catching a ball
•Unable to cross the vertical midline (for example, a right-handed child
may find it difficult to write on the left side of the page)
•Discrepancy between oral and written performance
•Disturb the development of visual tracking (necessary for reading and
writing)
•Bilateral integration (integrated use of the two sides of the body) may be
poor.

POSTNATAL PERIOD
1 – 4 weeks
NEONATAL PERIOD
•In prone position child lies
flexed and turns head from side to
side , head sags on ventral
suspension
•Motor response , grasp reflex are
active
•Shows visual preference to
human face
•Face is rounded and mandible is
small
•Abdomen – prominent with short
extremities

4th WEEK
•Holds chin up
•Head lifted momentarily to the plane
of the body on ventral suspension
•Watches person ,follows moving
object
•Begins to smile
8th WEEK •Head sustained in plane of body on
ventral suspension
•Smiles on social contact
•Listens to voice and coos

12th WEEK •Lifts the head and chest
•Lifts head above the plane of body on
ventral suspension
•Early head control with bobbing motion
•Makes defensive motion
•Listens to music

16th WEEK •Lifts head and neck
•Head is approximately in vertical axis
•Enjoys sitting with full truncal
support
•Laughs out loud
•Excites at site of food

28th WEEK •Rolls over , crawls
•Sits briefly
•Reaches out for and grasps large
objects
•Prefers mother and babbles
•Enjoys mirror

30th WEEK •Sits up alone , without support
•Walks holding on to the furniture
•Grasps objects with thumb and
forefinger
•Repetitive consonant
sounds(mama , dada)
•Responds to sound of name
•Plays peek a boo and waves bye

52nd WEEK
•Walks with one hand held , rises
independently
•Releases object to other person on
request
•Makes postural adjustments to
dressing

15 MONTHS
(PRESCHOOL
PERIOD)
•Walks alone
•Crawls upstairs
•Inserts pellets in bottle
•Indicates some desires or
needs by pointing
•Hugs parents

18
MONTHS
•Runs stiffly
•Walks upstairs with one hand held
•Explores drawers and waste
baskets
•Imitates scribbling
•Dumps pellet from bottle
•Vocabulary consistes of about 10
words
•Feeds self , seeks help when in
trouble

•Runs well , walks up & down the
stairs
•Opens door
•Jumps
•Circular scribbling
•Imitates horizontal stroke
•Puts 3 word together(subject , verb
, object)
•Handles spoon well
•Helps to undress
•Listens to stories with pictures
24
MONTHS

30 MONTHS •Climbs stairs with alternating feet
•Helps put things away
•Pretends in play
36 MONTHS •Rides tricycle
•Stands momentarily on one foot
•Imitates a cross , copies a circle
•Knows age and sex

48
MONTHS
•Hops on one foot
•Tells a story
•Plays with several children
•Goes to toilet alone
60
MONTHS
•Skips
•Dresses , undresses
•Asks questions about meaning of
words
•Domestic , role-playing

6 – 10
YEARS
•Steady growth until the
pre-pubertal growth spurts
10 – 12
YEARS
•Usual peak height velocity in girls

13 – 14
YEARS
•Usual peak height in boys
•Lymphatic tissues are at their peak
development during these years
•Growth rate declines after the peak height
•Velocity period to about the same as during
the infantile period
•Average weight gain during this period is 3 –
3.5 kg
•Average height gain during this period is 6 cm
(2.5 inches)

Childhood growth, schooling, and cognitive
development: further evidence from the Young
Lives study - Gunther Fink and Peter C Rockers
OBJECTIVE:
To use longitudinal data recently collected from 4 developing countries as
part of the Young Lives study, to investigate catch-up growth in children
between the ages of 8 and 15 y and the effects of growth during this late-
childhood and early-adolescence period on schooling and developmental
outcomes.

•RESULTS:
The study yielded 2 main results. First, 36% of children stunted at
age 8 y managed to catch up with their peers by age 15 y, and
those who caught up had smaller deﬁcits in cognitive scores than
did children who remained stunted.
 Second, physical growth faltering was not restricted to early
childhood but rather affected a substantial share of children in the
8–15-y age range, with large negative consequences for cognition
and schooling outcomes

10 YEARS
(PUBERTY &
ADOLESCEN
CE)
•On an average it begins in
female child
12 YEARS •Adolescence begins in male
child
13
YEARS
•Puberty coincides with development of
secondary sexual characteristics i.e;
breasts in female child , pubic hair ,
voice change in male child

EVENTS OF PUBERTY (13 YEARS)
IN MALES IN FEMALES
 Onset of hieght spurt
 Age of maximum spurt
 Achievement of adult hieght
 Genital changes begin within one
year of beginning of accentuated
height growth
 At about 12 years increased
amount of androgen is found in
urine
 Major growth phases concern
development of adult female
appearance
 Breast development
 Changes in body contour
 Genital development
 Height spurt usually 2 years
earlier than males

EVENTS OF PUBERTY (13 YEARS)
IN MALES IN FEMALES
 Changes in pubic , axillary ,
facial & body hair begins
 Height spurt peaks at about 14
years
 Strength spurt peaks at the end of
height spurt
 Secondary sex changes occur
shortly after this time
 Sterile period of 3 years from
menarche to reproduction is
possible
 Early sexual maturation is
accompanied by an advanced
skeletal age compared to
chronological age

•Sudden increase in growth
•Just after birth
•1 year after birth
•Mixed dentition growth spurt
 boys – 8 – 11 years
 girls – 7 – 9 years
•Adolescent growth spurt –
 boys – 14 – 16 years
 girls - 11 -13 years
GROWTH SPURTS

•Differentiate growth changes normal or pathologic
•Treatment of skeletal discrepancies is more advantageous in mixed
dentition period
•Pubertal growth spurt offers the best time in cases like predictability ,
treatment direction , time and management
•Arch expansion is carried out during the maximum growth period
•Orthognathic surgery should be carried out after growth ceases
GROWTH SPURTS – clinical significance

Genetic theory
•This theory was popularized by Allan
G. Brodie in 1940s
• head & face grew from growth
centres - under strict genetic control
•Primary, genetic control determines
certain initial features
•Secondarily , local feedbacks & inner
communication mechanisms between
cells & tissues.

CLEFT LIP AND PALATE
•Both genes and environmental factors, acting either
independently or in combination, are responsible for facial
clefting
•Treatment includes repetitive corrective surgeries and jaw
corrections

CONTRADICTION :
•if the face were under rigid genetic control,it would be
possible to predict features of children from
cephalograms of parents.
.
 LIMITATIONS: 1.Not explaining the role of
environmental & epigenetic factors
2.Primary genetic control determines only certain features
and doesn’t have complete influence on growth

Sutural theory
•In Sicher’s view, all bone – forming elements, cartilage, sutures
and periosteum are growth centers, which are responsible for
facial growth and assumed all were under tight intrinsic genetic
control.

APPLICATION:
•Closure of sutures in the cranium
•growth of maxilla happens at expansion of the circummaxillary
sutures which push maxilla down and forward

CRANIOSYNOSTOS
IS •A condition in which one or
more of the fibrous sutures in
an infant (very young) skull
prematurely fuses by turning
into bone (ossification),
thereby changing the growth
pattern of the skull.
•Treatment includes excision
of the prematurely fused
suture and correction of the
associated skull deformities

LIMITATIONS :
1.Independence of skull growth – inconsistent
2.Acc. to this theory – bone growth within maxillary
sutures – pushing apart of bones – thrust on whole maxilla
anteriorly & inferiorly. But any unusual pressure on bone
triggers resorption & not deposition. Deposition of new
bone is due to displacement rather than force that cause it.
3.Bone size and shape are profoundly influenced by
sutures. Experimentally, sutures are flexible
4.Transplantation of sutures to another site - no innate
growth potential.

Cartilaginous theory
•Intrinsic growth controlling factors –
present in cartilage Sutures only
secondary
•Prenatal importance of cartilagenous
portions of head Continue to dominate
post natally
• Sutures are passive & secondary
responsive to synchondrosis
proliferation & local environmental
factors

• Maxilla, consisting of the nasal
septum and nasomaxillary complex , which is
made up of cartilage, moves forward and
downward also by the forces from the nasal
septum.
• Bones in both maxilla and mandible respond
to their respective cartilaginous growth
centers.
•Therefore, cartilage at condyle,
cranial base synchondroses and
nasal septum can act as growth
centers.
APPLICATION

•Young bone possesses unique physical properties that coupled with
space occupying developing dentition give rise to patterns of fracture
not seen in adults.
•Bone fragments in children may become partially united as early as
4 days and fractures become difficult to reduce by seventh day.
• This results in need for different forms of fixation as early as
possible for comparatively shorter duration of time.
•Nonunion or fibrous union rarely occurs in children and excellent
remodeling occurs under the influence of masticatory stresses even
when there is imperfect apposition of bone surfaces.
CONDYLAR FRACTURES

FUNCTIONAL MATRIX
THEORY
MELVIN L MOSS in 1960 has formulated the
functional matrix theory
Functional matrices either :
•periosteal
• capsular.

•All non skeletal functional units adjacent to skeletal unit
form the periosteal matrices
•They act by bringing transformation of the related skeletal
units
•Example – coronoid process( microskelatal unit) and
temporalis muscle (periosteal matrix)
PERIOSTEAL
MATRIX

•Capsule surrounding spaces & masses 4 cranial capsules are :
Neurocranial Orofacial Otic Orbital
•Sandwitched between two covering layers with spaces in
between, filled with loose connective tissue
• Capsules expands due to volumetric increase of capsular
matrix- translation of embedded bone
CAPSULAR MATRIX

APPLICATION
•Mandibular growth is now seen to be a
combination of morphologic effects of both
capsular and periosteal matrices
•The capsular matrix growth causes an expansion of
the capsule as a whole
•The enclosed and embedded macrosekeletal unit
(mandible) accordingly is passively and secondarily
translated in space to successively new positions

•Prognathism is the positional relationship of
the mandible or maxilla to the skeletal base where
either of the jaws protrudes beyond a predetermined
imaginary line in the coronal plane of the skull
•The most common treatment for
mandibular prognathism is a combination
of orthodontics and orthognathic surgery.
The orthodontics can involve braces,
removal of teeth, or a mouthguard.
MANDIBULAR PROGNATHISM

FACTORS AFFECTING GROWTH
HEREDITARY AND GENETIC FACTORS
1. Phenotype
2. Characteristics of parents
3. Race
4. Sex
5. Bio-rhythm
6. Genetic disorders

FACTORS AFFECTING GROWTH
ENVIRONMENTAL FACTORS
Prenatal environment
Postnatal environment –
Nutrition
Infections and infestations
Trauma
Socio – economic level
Climate
Cultural factors
Emotional factors
Ordinal position in the family

HERIDITARY & GENETIC FACTORS
1.PHENOTYPE :-
•A phenotype is any observable characteristic or trait of an organism:
such as its morphology , development , biochemical or physiological
properties or behaviour
•Parental traits are transmitted to the offsprings
•Height , size of the head , structure of the chest , fatty tissue etc..have
better genetic association than other somatic characteristics

HERIDITARY & GENETIC FACTORS
2. CHARACTERISTICS OF PARENTS
•Parents of high IQ having children of the same and vice versa
•(further enhanced by environmental stimulation
3.RACE
•Growth potential of children of different racial groups is different
•e.g; african , american asian

HERIDITARY & GENETIC
FACTORS
4.SEX
•Boys are heavier & taller than girls and this is maintained till 11 years of
age
•Pre pubertal growth spurt occur earlier in girls
•Once again the boys grow taller than girls once they reach the pre
pubertal growth spurt
5.BIO-RHYTHM & MATURATION
•Daughters attaining menarche at similar age a their mothers
•Similar length of menstural cycle

HERIDITARY & GENETIC FACTORS
•Growth & development are adversely affected by certain
genetic disorders
1. CHROMOSOMAL ABNORMALITIES
E.G: turner syndrome , down syndrome
2. GENE MUTATIONS
e.g:metabolic defects like galactosemia ,
mucopolysaccharidosis

ENVIRONMENTAL FACTORS
PRENATAL FACTORS:
Maternal nutritional deficiencies
Malpositions
Metaboli , endocrine disturbances
Infectious disease(rubella , toxoplasmosis , syphilis ,
herpes)
Rh compatibility , smoking , alcohol and intake of
certain drugs

POSTNATAL FACTORS
•NUTRITION:
Growth of children suffering from protein – energy
malnutririon, anemia and vitamin deficiency status is
retarted
Overeating and obesity accelerates the somatic
growth

•INFECTIONS AND INFESTATIONS
Persistent and recurrent diarrhoeas leads to growth
impairment
Systemic and parasitic infections decrease the velocity of
growth
•TRAUMA:-
Fracture of the end of the bone damages the growing
epiphysis and thus hampers growth
Head injury may cause brain damage and affect the
mental development of child

Parasitism in Children Aged Three Years and Under:
Relationship between Infection and Growth in Rural
Coastal Kenya
Monica Nayakwadi Singer et al
•Objective : to document the prevalence of parasitic infections and
examine their association with growth during the first three years
of life among children in coastal Kenya.
•Children enrolled in a maternal-child cohort were tested for soil
transmitted helminths (STHs: Ascaris, Trichuris,
hookworm, Strongyloides), protozoa (malaria, Entamoeba
histolytica and Giardia lamblia), filaria, and Schistosoma infection
every six months from birth until age three years. Anthropometrics
were measured at each visit.

•Of 545 children, STHs were the most common infection with 106
infections (19%) by age three years.
•Malaria followed in period prevalence with 68 infections (12%) by three
years of age.
• Filaria and Schistosoma infection occurred in 26 (4.8%) and 16 (2.9%)
children, respectively.
• Seven percent were infected with multiple parasites by three years of age.

•Each infection type (when all STHs were combined) was documented
by six months of age.
•Decreases in growth of weight, length and head circumference during
the first 36 months of life were associated with
hookworm, Ascaris, E. histolytica, malaria and Schistosoma infection.
•In a subset analysis of 180 children who followed up at every visit
through 24 months, infection with any parasite was associated with
decelerations in weight, length and head circumference growth
velocity.
•Multiple infections were associated with greater impairment of linear
growth.

SOCIO – ECONOMIC STATUS
High socio – economic status =superior
nutritional status and hence fewer infections
Poverty =nutritional deficiency and hence
diminished growth
CLIMATE
Velocity of growth may alter in different
season(usually higher in spring and low in summer
months
Infections and infestations are common in hot
and humid climates

SURVEY ON THE RELATIONSHIP BETWEEN PARENT
SOCIOECONOMIC STATUS AND PRESCHOOL
CHILDREN GROWTH IN AHVAZ CITY 2015
Moradi, Behzad
•This study aimed to investigate the relationship between
socioeconomic level of the parents on weight gain and height growth
of preschool children in Ahvaz 2015.
•The results of this study showed that weight gain is connected to mother`s
education (P=0.013) and parent`s income (P<0.048).
• when the mother`s education and monthly income are higher, children
weight gain would be more appropriate.
•Other variables didn`t affect either the children height growth or weight
gain (P>0.05).

•CULTURAL FACTORS
Methods of child rearing and infant feeding in the community are
determined by the cultural habits
Some religious taboos (related to food stuff) also affect the growth
and development
•EMOTIONAL FACTORS
Emotional trauma from unstable family , insecurity
Sibling jealousy and revelry , inadequate schooling etc.. Have a
negative effect on growth and development

•ORDINAL POSITION IN THE
FAMILY
FIRST BORN CHILD – gets more attention
THE ONLY CHILD –develops more rapidly & intellectually
than the other children with siblings
THE MIDDLE CHILD – gets less attention and is less
achievement oriented than the first born
YOUNGEST CHILD – more peer oriented , less achievement
oriented , less intellectually inclined , but gets great deal of love
& attention ( therfore develops good nature , warm personality
and high self esteem

GROWTH ASSESSMENT
BIOMETRICS:
Biometrics is defined as science of statistical biology ,the collection
and statistical analysis of data regarding a living organism.
1.Longitudinal methods —these imply serial measurements in the
same individual or population over a long period of time.
• their advantage lie in the fact that individual patterns can be defined
and the variation within the group can be analyzed .

2. Cross sectional method –groups of varying ages or at varying
stages in development are examined only once.
3. Semi longitudinal- monitoring age groups or subgroups at
different level of development only for that period which
separate one group from another

RADIO ISOTOPES
•When injected into the tissues get incorporated into the
developing bone and act as in vivo markers.
•Tc 33 is the most commonly used isotope.
VITAL STAINING
•Administration of certain dyes to the experimental animals
which incorporated in the bones.
• e.g.—Alizarin red 5,tetracyclin.

 NATURAL MARKERS —
•Certain histological features present in the normal bone such as
nutrient canals ,lines of arrested growth and certain prominent
trabeculae can be used as natural markers.
STERIOTYPES —
• A computer analysis in which positional changes can be studied in
a three dimensional system.
CRANIOMETRY—
•Metric study of cranial dimensions in dry skulls. less suitable for
descriptive purpose

HEIGHT AND WEIGHT
•Growth velocity curve for early, average and late maturating
indicate that earlier the adolescent growth spurt occurs, the
more intense it appear to be

Hieght & Weight
measurement in infant:
•Measuring tape – in cm
•Baby weighing scales – in
pounds
•Full term – 18 in.(45.7cm) to 22
in (60 cm)
•Full term - 5 pounds(2.6 kg ) –
8 pounds(3.8 kg)

Measurement
of height &
Weight in a
child

ROCHE(1980)categorized SIX type of height growth in children
• Average growers -follows middle range distance curve and
comprise two third of all the children.
• Early maturing -taller in child hood as matured faster not
particularly tall as adults.
• Genetically tall —taller than average children and will be tall as
adults .

•Late maturing –shorter than average in childhood and will be adults
of average stature.
• Genetically short —short in childhood and as adults as well.
• Children who start puberty either very late or very early
subsequently have either much less or much more growth in height
than expected.

HAND WRIST RADIOGRAPHS
•Numerous small bones which show a
predictable sequence of ossification from
birth to maturity
•Ossification of the bones of hand and
wrist is standard for skeletal development.
•Ossification and development of bones
form a chronology of skeletal development

GREULICH AND PYLE METHOD
•Published an atlas containing ideal skeletal age
pictures of hand - wrist for different
chronological age and for each sex
•Each photograph in the atlas is representative
of a particular skeletal age
•The patient’s radiograph is matched on an
overall basis with one of the photograph in the
atlas

BJORK , GRAVE AND BROWN METHOD

FISHMAN’S SKELETAL MATURITY INDEX

SCAMMONS’ Growth curve
•Different tissues in the body grow at
different times and different rates
•NEURAL TISSUES : completes
90% of growth at 6 years and 98% by
10 years of age
•LYMPHOID TISSUES:
Proliferates rapidly in late childhood
and reaches almost 200% of adult
size
By about 18 years of age the tissues
undergo involution to reach adult size

•GENERAL TISSUES
Exhibits an ‘s’ shaped curve with
rapid growth upto 2- 3 years of age
followed by a slow phase of growth
between 3 – 10 years
After 10 years a rapid phase of
growth occurs terminaating by 18 -
20 years
•GENITAL TISSUES
Grows rapidly at puberty leading
adult size after which growth ceases

GROWTH TRENDS
•Proposed by tweed
•According to the growth trends he divide individuals into threee
groups
TYPE A
•The maxilla and mandible grow together thus ANB angle
remains unchanged.This is accompanied with class-I relationship
and in mixed dentition, it does not exceed 4.5 degree.No treatment
is indicated in this case

TYPE A SUBDIVISION
•In this condition maxilla is protruding with the ANB angle
moe than 4.5 degree
•The treatment is to restrict the growth of maxilla allowing to
catch up
•The prognosis is good , but at times requires the extraction of
premolars

TYPE B
•The maxilla and mandible are foound to be grow forwards and
downwards with the growth of maxilla exceeding the mandible
•This type of growth trends have a poor prognosis
•Growth of middle and lower face is predominantly in the vertical
directions

TYPE B SUBDIVISON
•The ANB angle is large continuous to grow , indicating an unfavourable
growth trend
TYPE C
•The maxilla and mandible grow forwards and backwards with mandible
growing forward more rapidly than the maxilla
•The ANB angle seen to be decreasing , with the middle catching up with
the maxilla
•Treatment is not indicated until eruption of canine

TYPE C SUBDIVISION
•Mandible is found to be growing more forward to compare with maxilla
•Mandibular incisors touch the lingual surface of maxillary incisors

DEVELOPMENTAL MILESTONES
 Developmental milestones are the points in time when a child
learns to accomplish a specific task.
 Although children grow and develop at their own pace, these
milestones are established to mark the average age moments
most children learn the specific task.

THE FOUR DOMAINS OF DEVELOPMEN
These are:
• gross motor
•vision and fine motor
•hearing, speech and
language
•social, emotional and
behavioural

GROSS MOTOR FUNCTION
 As a child develops, signs of impaired or delayed gross
motor function may be noticeable.
 The ability to make large, coordinating movements using
multiple limbs and muscle groups is considered gross
motor function.
 Impaired gross motor functions – limited capability of
accomplishing common physical skills such as walking,
running, jumping, and maintaining balance.

 Significant milestones of gross motor function include:
• Rolling
• Sitting up
• Crawling
• Standing
• Walking
• Balancing

Fine Motor Function:
Fine motor control encompasses many activities that are learned, and
involve a combination of both mental (planning and reasoning) and
physical (coordination and sensation) skills to master.
Examples:
•Grasping small objects
•Holding objects between thumb and forefinger
•Setting objects down gently
•Using crayons, Turning pages in a book

Breastfeeding and motor development in term and
preterm infants in a longitudinal US cohort
Kara A et al–AMERICAN JOURNAL OF CLINICAL NUTRITION
OBJECTIVE: To estimate associations between infant feeding and time
to achieve major motor milestones in a US cohort.
Results: The prevalence of exclusive breastfeeding in preterm
infants was lower than in term infants at 4 mo postpartum (8%
compared with 19%).
After adjustment for confounders, term infants who were fed solids in
addition to breast milk at 4 mo postpartum achieved both standing
[acceleration factor (AF): 0.93; 95% CI: 0.87, 0.99] and walking (AF:
0.93; 95% CI: 0.88, 0.98) 7% faster than did infants who were
exclusively breastfed, but these findings did not remain statistically
significant after correction for multiple testing.

CLINICAL IMPLICATIONS OF GROWTH
ETIOLOGY OF MALFORMATIONS
•Genetic
•Intrauterine & neonatal environment
•Genetic influences

VARIOUS CRANIOFACIAL DEFECTS
ACEPHALY –
absence of head
ANENCEPHALY
–absence of brain
ACRANIA
–absence of skull

ACALVARIA
-roofless skull
CRANIOSCHIS
IS – fissured
cranium
PREMAXILLARY
AGENESIS
-median cleft lip /
palate

PREMAXILLA
RY
DYSGENESIS
-bilateral cleft
lip/palate
AGNATHIA
-absent
mandible
MANDIBULAR MIDLINE
CLEFT
-failure of merging of
mandibular prominence

MICROSTOMI
A -Small mouth
MACROSTOMI
A –
Large mouth
MICROGNATHIA –
retardation of
mandibular
development

MALFORMATION SYNDROMES ASSOCIATED
WITH MANDIBULAR DEFICIENCY
1.PIERRE ROBIN
SYNDROME
• A condition in which an
infant has a smaller than
normal lower jaw, a tongue
that falls back in the throat,
and difficulty breathing. It
is present at birth.

2.TREACHER COLLINS
SYNDROME:
TCS is usually autosomal dominant
disorder
SIGNS & SYMPTOMS:
•Underdevelopment of lower jaw
•Underdevelopment of zygomatic bone
•The external ear is sometimes small ,
rotated or absent.

WITH MANDIBULAR PROGNATHISM
1.GORLIN SYNDROME:
Gorlin–Goltz syndrome, is an inherited
medical condition involving defects within
multiple body systems such as
the skin, nervous system, eyes, endocrine
system and bones
SYMPTOMS
• Distinct faces: frontal and temporoparietal
bossing, hypertelorism, and mandibular
prognathism
• Skeletal abnormalities: bifid ribs,
kyphoscoliosis, early calcification of falx
cerebri

2.KLIENFILTER SYNDROME
Klinefelter syndrome (KS) also
known as 47,XXY or XXY, is the
set of symptoms that result from
two or more X chromosomes in
males

WITH FACIAL HIEGHT /SYMMETRY
1.BECKWITH – WEIDMANN SYNDROME
Is an overgrowth disorder usually present at birth, characterized by
an increased risk of childhood cancer and certain congenital features

NEONATAL JAUNDICE
•Neonatal jaundice is a yellowish discoloration of the white part of the
eyes and skin in a newborn baby due to high bilirubin levels..
•High bilirubin levels in infants is due to immature liver and deficiency of
enzymes like UDP glucuronosyltransferases (UGTs)

Symptoms include :
•Yellow coloring of baby’s skin (usually
beginning on the face and moving down to the
body)
•Poor feeding or lethargy
•Sleepiness
•Brown urine
•High – pitch cry
•Fever
•Vomiting

TREATMENT :
•Physiological jaundice usually does not require treatment
•Fades away gradually within one to two weeks
•May require phototherapy ( a special light treatment)

CONCLUSION
•The healthy growth and development of infants and young children is of
paramount importance for children to develop their full physical and
mental potentials.
•Child growth is internationally recognized as the best global indicator
of physical well-being in children
•The consequences of poor child growth in terms of mortality, morbidity,
and impaired cognitive development are severe and far-reaching.

REFERENCES
•Human embryology – Inderbir singh
•Comtemporary orthodontics – Profitt
•Orthodontics – current principles and techniques-Graber
•Textbook of Pediatric Dentistry – Nikhil Marwah
•Handbook of Orthodontics – Robert.C. Moyers
•Human Embryology – William .J.Larse

REFERENCES
•Comparison of developmental milestone attainment in early treated HIV-
infected infants versus HIV-unexposed infants: a prospective cohort study –
Sarah benki nugent et al
•Breastfeeding and motor development in term and preterm infants in a
longitudinal US cohort-Kara A et al–AMERICAN JOURNAL OF
CLINICAL NUTRITION
•Parasitism in Children Aged Three Years and Under: Relationship between
Infection and Growth in Rural Coastal Kenya-Monica Nayakwadi Singer et
al
•SURVEY ON THE RELATIONSHIP BETWEEN PARENT
SOCIOECONOMIC STATUS AND PRESCHOOL CHILDREN GROWTH
IN AHVAZ CITY 2015 -Moradi, Behzad

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