Growth predictions /certified fixed orthodontic courses by Indian dental academy

GROWTH
PREDICTION
INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com

• Introduction
• Handwrist radiographs
• Cervical vertebrae
• Mid-palatal suture
• Frontal sinus
• Mandibular canine calcification
• Arcial growth prediction
• Parental Data
• Craniofacial templates
Content

• Even when excellent data from clinical trials are
available, it is difficult to predict how any one
individual will respond to particular plan of
treatment .Variability must be expected.
• In orthodontics, two interrelated factors
contribute most of the variability: the patient’s
growth pattern and the effect of treatment on the
expression of growth.

• At present, in the absence of
growth, treatment responses are
reasonably predictable.
Growth is not predictable.

Growth spurts - Graber
• Childhood growth spurt (3 yrs)
• Juvenile growth spurt
girls – 6 to 7 yrs
boys – 7 to 9 yrs
• Pubertal growth spurt
girls – 10½ to 13 yrs
boys – 12½ to 16 yrs

Pubertal growth spurt-girls
• Stage-I : beginning of growth spurt
10½ to 11½yrs
• Stage-II : peak velocity
lasts for 1 to 2yrs
• Stage-III : menarche
deceleration and end of growth spurt.

Pubertal growth spurt-boys
• Stage-I : beginning of growth spurt
lasts for 1 yr (fat spurt)
• Stage-II : fat redistribution, pubic hairs
lasts for 1 to 2yrs
• Stage-III : peak velocity
lasts for 1 to 2yrs
• Stage-IV : height stagnates
deceleration and end of growth spurt.

Hand Wrist Radiographs
• Chronological age is often not sufficient for
assessing the developmental stage and
maturity of the patient.
• Thus, biological age has to be determined.
• Hand Wrist radiographs are an effective tool
to assess the biological age.

• 1st hand wrist film was published by Sydney
Rowland in England in april 1890 (4 months
after discovery of x-rays).
Review of literature

• In the early
1900s, Pryor(1907), Rotch(1908), and
Crampton(1908) began tabulating indicators
of maturity on sequential radiographs of the
growing hand and wrist.
• Todd(1937) compiled hand-wrist data that
was further elaborated on by Greulich and
Pyle(1959) in atlas form.

• Flory in 1936, indicated that the beginning of
calcification of the adductor sesamoid was a
good guide to determining the period
immediately before puberty.
• Peak height velocity follows adductor
sesamoid appearance by approximately 1
year.

• Fishman(1979) developed a system of hand-
wrist skeletal maturation indicators (SMIs)
using four stages of bone maturation at six
anatomic sites on the hand and the wrist.
• Hagg and Taranger(1980) created a method
using the hand-wrist radiograph to correlate
certain maturity indicators to the pubertal
growth spurt.

• Hunter reported that carpal bones had proved
to be the best site for determining skeletal
maturation.
• Björk and Helm stated that appearance of ulnar
sesamoid on hand wrist film was related to the
onset of maximum pubertal growth in height.
• Helm elaborated on other structures in the
hand wrist film to pubertal growth spurt.

Indications
• Prior to rapid maxillary expansion.
• Marked discrepancy between dental or
skeletal and chronological age.
• Where maxillomandibular changes are
indicated e.g. skeletal class II or III or skeletal
openbite.
• Orthognathic surgery if undertaken between
the ages of 16-20 years.

ANATOMY

PA view

Oblique view

• The ossification events are localized in the
area of the phalanges, carpal bones, and
radius (R).
• Growth stages of the fingers are assessed
according to the relationship between the
epiphyses and the diaphyses.
Björk, Grave and Brown’s method
American Journal of Orthodontia. 1976; 69:611-20.www.indiandentalacademy.com

Three stages of ossification of
the phalanges
First stage
Second stage
Third stage

9 stages:
Stage 1(males-10.6 yrs, females 8.1yrs):
epiphysis and diaphysis of proximal phalanx of
index finger are equal.
3 yrs before peak of pubertal growth spurt.

First Stage (PP2 = - Stage)

epiphysis and diaphysis of middle phalanx of
middle finger are equal.

Second Stage (MP3 = - Stage)

Stage 3(males-12.6 yrs, females 9.6yrs): 3 stages
• Ossification of hamular process of hamate.
• Ossification of pisiform.
• Epiphysis and diaphysis of radius has same
width.

Third stage
(Pisi-, H1-, and R = - Stage)

Stage 4(males-13.0yrs, females 10.6yrs):
Initial mineralization of ulnar sesamoid of
thumb.
Increased ossification of the hamular process of
hamate.
Shortly before or at the beginning of the
pubertal growth spurt.

Fourth stage
(S- and H2-stage)

Stage 5(males-14 yrs, females 11yrs):
Capping of diaphysis is seen in
• Middle phalanx of 3rd finger.
• Proximal phalanx of thumb.
• Radius.
marks the peak of pubertal growth.

Fifth stage
(MP3cap ;PP1cap ;and Rcap-stage)

Stage 6(males-15 yrs, females 13.3yrs):
Visible union of diaphysis and epiphysis at the
distal phalanx of the middle finger.
Signifies end of pubertal growth spurt.

Sixth stage
(DP3u-stage)

Stage 7(males-15.9 yrs, females 13.9 yrs):
Visible union of the epiphysis and diaphysis at
the proximal phalanx of middle finger.

Seventh stage
(PP3u-stage)

Union of epiphysis and diaphysis at middle
phalanx of middle finger.

Eighth stage
(MP3u-stage)

Stage 9(males-18.5 yrs, females 16 yrs):
Complete union of epiphysis and diaphysis of
radius.
Ossification of all bones is complete and skeletal
growth is complete.

Ninth stage
(Ru-stage)

An Overview

Correlation table between ossification stages of
hand bones and the skeletal age for the period
between 8 and 18 years

Fishman’s skeletal maturity indicator
• In 1982 – Leonard Fishman gave system of
skeletal maturation assessment (SMA).
• 11 skeletal maturity indicators (SMI’s) were
described.
Maturational patterns and prediction during adolescence.
Leonard Fishman. Angle Orthodontist: No. 3: 1987:178-193

11 SMI were divided into 4 stages
• Epiphysis as wide as diaphysis.
• Ossification.
• Capping of epiphysis.
• Fusion of epiphysis and diaphysis.

Epiphysis as wide as diaphysis
1. Third finger-proximal phalanx
2. Third finger-middle phalanx
3. Fifth finger-middle phalanx

Ossification
4. Adductor sesamoid of thumb.

Capping of epiphysis
5. Third finger – distal phalanx.
6. Third finger – middle phalanx.
7. Fifth finger – middle phalanx.

Fusion of epiphysis and diaphysis
8. Third finger – distal phalanx.
9. Third finger – proximal phalanx.
10. Third finger – middle phalanx.
11. Radius.

• Accelerating growth velocity period (1–4)
• High growth velocity period (4–7)
• Decelerating velocity period (7–11)

Conclusion
• SMI occurs at earlier chronological ages for girls.
• SMI make it possible to judge an individual
relative timing of maturation – whether it is
early, average or late.
• Comparison of boys and girls on maturational
time scale shows no sexual differences in the
percentages of completion of incremental growth
at same SMI levels, regardless of chronological
age.

• Early maturers of both sexes exhibited almost
identical SMI duration values for SMI’s 1-5 & 7-
11. The only significant difference in SMI
duration for early group is between SMI 5 & 6.
Girls in general reach the point of peak velocity
of growth at SMI 5, and boys at SMI 6.

• In late maturation groups, considerably less
correlation is found between male and female
groups, although duration of time between
SMI’s 1-2 and 10-11, at beginning and end of
adolescent period, are very similar.

Levels of maturation - FEMALE

Levels of maturation - MALE

Julien Singer method
Six stages are described:
• Stage 1 (early) :
Pisiform is absent.
Hook of hamate absent.
Epiphysis of proximal phalanx of 2nd finger being
narrow than diaphysis.
Angle orthodontist: 1980, 322-333www.indiandentalacademy.com

• Stage 2 (prepubertal) :
Proximal phalanx of 2nd finger is equal to its
epiphysis.
Initial ossification of hook of hamate.
Initial ossification of pisiform.
• Stage of adolescent growth spurt during which
significant amount of growth is possible.

• Stage 3 (pubertal onset):
Calcification (beginning) of ulnar sesamoid.
Increased width of proximal phalanx of 2nd
finger.
Increased calcification of hook of hamate.
Increased calcification of pisiform.

• Stage 4 (pubertal stage):
Calcification of ulnar sesamoid.
Capping of diaphysis of middle phalanx of 3rd
finger by its epiphysis.

• Stage 5 (pubertal deceleration):
Full calcification of ulnar sesamoid.
Fusion of epiphysis of distal phalanx of 3rd finger
with its diaphysis.
Epiphysis of radius and ulna not fused
completely with diaphysis.
Phalanges and carpels are fully calcified.

• Stage 6 (growth completion):
No remaining growth site is seen.

Maturation indications and pubertal
growth spurt
• Urban Hägg and John Taranger did a study in
1982 to investigate pubertal growth spurt and
dental, skeletal and pubertal development.
Am J Orthod: 82: oct 1982

Method of analysis
• Adolescent growth: was studied by graphic
analysis of the unsmoothed incremental
curves of standing height. These curves were
based on the annual increments from 3 to 20
years.

Method of analysis
• Dental
development was
assessed by
dental
emergence stages
(DES).

Method of analysis
• Skeletal development in the hand and wrist was
analyzed from annual radiographs, taken
between the ages of 6 and 18 years, by
assessment of the ossification of the ulnar
sesamoid of the metacarpophalangeal joint of
the first finger (S) and certain specified stages of
three epiphyseal bones (closure of epiphyseal
plates): the middle and distal phalanges of the
third finger (MP3 and DP3) and the distal
epiphysis of the radius (R).

Method of analysis
• Pubertal development was assessed from 10
to 18 years by determining the occurrence of
menarche in girls and the voice change in
boys.

3 stages of voice changes were used:
• PPV – prepubertal voice; the pitch of the
voice had not changed noticeably.
• PV – pubertal voice; the pitch of the voice
had changed noticeably but the voice had
not yet acquired adult characteristics.
• MV – male voice; the pitch of the voice had
acquired adult characteristics.

Pubertal growth spurt

Results
• The pubertal growth spurt – ONSET of spurt is the
annual increment from which there is a marked
continuous increase in growth rate of PHV (peak
height velocity). ONSET is found by locating the
smallest annual increment (A) from which there is
continuous increase in growth rate to PHV. On
average, the pubertal growth spurt began
(ONSET) at 10.0 & 12.1 yrs. and ended (END) at
14.8 & 17 yrs in girls and boys respectively. In
both sexes PHV occurred 2 yrs ONSET, i.e. at
12.0yrs in girls and 14.1yrs in boys.

Results
• Dental development and pubertal growth
spurt - The dental development was more
advanced in boys than in girls at all three
pubertal growth events.
• The dental emergence stages were not
useful as indicators of the pubertal growth
spurt.

Results
• Skeletal development and the pubertal
growth spurt - Skeletal development at
ONSET and PHV was more advanced in girls
than in boys, whereas at END the skeletal
development was more advanced in boys.

The skeletal stages were useful as indicators
of the pubertal growth spurt.
Skeletal stages:
• Sesamoid – it appeared during the
acceleration period of pubertal growth spurt
(ONSET - PHV).

Middle third phalanx:
• MP3-F - was attained before ONSET by about
40 percent of the subjects and at PHV by the
last subjects. The epiphysis is as wide as
metaphysis.
• MP3-FG – epiphysis is as wide as metaphysis
and there is distinct medial and/or lateral
border of the epiphysis forming a line of
demarcation at right angle to distal border.
This stage is attained by 1yr before or at PHV.

• MP3-G – the sides of the epiphysis have
thickened and also caps its metaphysis
forming a sharp edge distally at one or both
sides. This stage is attained at or 1 yr after
PHV.
• MP3-H – fusion of epiphysis and metaphysis
has begun. It is attained after PHV but before
the END.
• MP3-I - fusion of epiphysis and metaphysis is
complete. It was attained before or at END in
all subjects.

Distal third phalanx:
• DP3-I – it is attained during the deceleration
period of the pubertal growth spurt. The
fusion of epiphysis and metaphysis is
complete.
Radius:
• R-I – it is attained 1 yr before or at the END.
Fusion of the epiphysis and metaphysis has
begun.
• R-J - Fusion of the epiphysis and metaphysis
is complete.

Pubertal development and pubertal
growth spurt
• Pubertal development (menarche and voice
change) and pubertal growth events has a
close relationship in both sexes.
• Menarche occurred 1.1yr after peak height
velocity. The pubertal voice was attained 0.2
yrs before PHV and male voice 0.9yrs after
PHV.

Discussion
• Reliable indications taken from skeletal
development were found for PHV and END but
not for beginning (ONSET) of pubertal growth
spurt.
• During the end of the prepubertal period the
radiographic changes in the form of bones of
hand wrist are small. Therefore there is a lack
of indications during this period.

CERVICAL VERTEBRAE
MATURATION

• 1972 – Lamparski was the 1st person to study
cervical vertebrae and he found them to be as
reliable as hand wrist film.
• He found that cervical vertebrae indicators
were same for males and females, but the
females developed the changes earlier.

• 1n 1995 – Hassel and Farman modified the
Lamparski criteria by using C2, C3, and C4
cervical vertebrae.

Lamparski method
• Stage 1 – the inferior borders of the bodies
of all cervical vertebrae are flat. The superior
borders are tapered from posterior to
anterior.
• Stage 2 – a concavity develops in the inferior
border of the second cervical vertebrae. The
anterior vertical height of bodies increase.

Lamparski method
• Stage 3 – a concavity develops in the inferior
border of the third vertebrae.
• Stage 4 – a concavity develops in inferior
border of 4th vertebrae. Concavities in lower
border of 5th and 6th vertebrae are beginning
to form. The bodies of all cervical vertebrae
are rectangular in shape.

Lamparski method
• Stage 5 – concavities are well defined in the
lower border of the bodies of all 6 cervical
vertebrae. The bodies are nearly square in
shape.
• Stage 6 – all concavities have deepened. The
vertebral bodies are now higher than they
are wide.

Cervical vertebrae maturation
indicators using C3 as guide.

Brent Hassel, Allan Farman
• Category 1 (Initiation) – at this stage
adolescent growth was just beginning and
80% to 100% of the growth was expected.
Inferior borders of C2, C3 and C4 were flat at
this stage. The vertebrae are wedge
shaped, and the superior vertebral border
were tapered from posterior to anterior.
AJODO: Jan 1995

CVMI 1

Category 2 (Acceleration) – growth
acceleration was beginning at this stage with
65% to 85% of adolescent growth expected.
• Concavities were developing in the inferior
border of C2, C3.
• The inferior border of C4 was flat.
• The bodies of C3 and C4 were nearly
rectangular in shape.

CVMI 2

Category 3 (Transition) – adolescent growth
was still accelerating at this stage towards
peak height velocity with 25% to 65% of
adolescent growth expected.
• Distinct concavities were seen in the inferior
borders of C2 and C3.
• Concavity was beginning to develop in the
inferior border of C4.
• The bodies of C3 and C4 were rectangular in
shape.

CVMI 3

Category 4 (Deceleration) – adolescent
growth began to decelerate dramatically at
this stage with 10% to 25% of adolescent
growth expected.
• Distinct concavities were seen in the inferior
borders of C2, C3 andC4.
• The vertebral bodies of C3 and C4 were
becoming more square in shape.

CVMI 4

Category 5 (Maturation) – final maturation
of the vertebrae took place during this
stage, with 5% to 10% of adolescent growth
expected.
• More accentuated concavities were seen in
the inferior borders of C2, C3 and C4.
• The bodies of C3 and C4 were nearly square
to square in shape.

CVMI 5

Category 6 (Completion) – growth was
considered to be complete at this stage.
• Deep concavities were seen in the inferior
borders of C2, C3 and C4.
• The bodies of C3 and C4 were square or
were greater in vertical dimension than in
horizontal dimension.

CVMI 6

Cervical Vertebral Maturation
(CVM) Method for the Assessment of
Mandibular Growth
• Greatest effects of functional appliances take
place when the peak in mandibular growth is
included in treatment period.
• Tiziano Baccetti, Lorenzo Franchi, James A.
McNamara Jr.
Angle Orthod 2002;72:316–323.

Components of study
• C2, C3 andC4.
• 706 subjects.
• Co-Gn = total mandibular length.
• Maximum increment between two
consecutive cephalograms defines peak in
mandibular growth at puberty.
• Six consecutive cephalograms.

• Lambarski’s CVM I and CVM II are merged
(CVMS I).
• CVMS = cervical vertebrae maturation stage.
• 5 maturational stages.

CVMS I
• Lower border of C2, C3 and C4 is flat.
• C2 may present slight concavity.
• Bodies of C3 and C4 are trapezoidal.
• Peak mandibular growth will occur not
earlier than 1yr after this stage.

CVMS II
• Concavities present at the lower border of C2
and C3.
• Bodies of C3 and C4 – either trapezoid or
rectangular horizontal in shape.
• Peak in mandibular growth will occur within
1yr after this stage.

CVMS III
• Concavities at the lower border of C2, C3 and
C4 are present.
• Bodies of C3 and C4 – rectangular horizontal
in shape.
• Peak in mandibular growth has occurred
within two years before this stage.

CVMS IV
• Concavities at the lower border of C2, C3 and
C4 are present.
• At least one of the bodies of C3 and C4 is
squared in shape.
• The peak in mandibular growth has occurred
not later than one year before this stage.

CVMS V
• The concavities at the lower borders of
C2, C3, and C4 still are evident.
• At least one of the bodies of C3 and C4 is
rectangular vertical in shape.
• The peak in mandibular growth has occurred
not later than two years before this stage.

Discussion
• When CVMS 1 is diagnosed in the individual
patient with mandibular deficiency, clinician
can wait least 1 year for a radiographic re-
evaluation aimed to start treatment with
functional appliances.
• CVMS 2 represents the ideal stage to begin
functional jaw orthopedics.

Mid palatal suture region as an indicator of
maturity
• Revelo and Fishman in 1994 evaluated the
ossification pattern of the mid palatal suture.
• Maturational evaluation was accomplished by
examining the hand wrist radiographs with
Fishman’s system of SMA.
Revelo, Fishman AJO: 105:mar 1994.www.indiandentalacademy.com

Key landmarks and planes
• Point A – most anterior point on premaxilla.
• Point B – most posterior point on the
posterior wall of the incisive foramen.
• Point P – point tangent to a line connecting
the posterior walls of the greater palatine
foramen.

Key landmarks and planes
• A-P – total dimension of the suture.
• A-B – anterior dimension of the suture.
• B-P – posterior dimension of the suture.

Results
• Significant correlation between maturational
development and beginning of ossification of
mid palatal suture.
• Before SMI 4 i.e. before ossification of
adductor sesamoid, very little or no
midpalatal approximation exists.
• Suture is only 8% fused at SMI 3.
• Anterior portion of suture is wide open.

Results
• SMI 4-7 i.e. ossification of adductor
sesamoid, capping with distal and middle
phalanx of 3rd finger, osseous interdigitation is
evident with approximation in some areas.
• This period occurs during the pubertal growth
spurt.

Results
• After SMI 8 i.e. fusion of distal phalanx of 3rd
finger, the suture demonstrates a marked
increase in rate of approximation.
• At maturational age SMI 11 i.e. fusion of
radius, 50% of total midpalatal suture is
approximated.
• High percentage of approximation occurs
posteriorly.

Results
• No difference in patterns of approximation
between males and females.
• Thus, best time to use orthopedic force for
expansion is before SMI 9 as percentage of
approximation is less.
• Ideal time is SMI 1 to 4 as less orthopedic
force is required.

Frontal sinus development as an indicator
for somatic maturation at puberty
Am J Orthod Dentofac Orthop 1996; 110:476-82.

• Sabine Ruf and Hans Pancherz.
• The study was performed on 53 adolescent
boys, and the frontal sinus size development was
assessed on lateral head films.
• Two head films from each subject were analyzed
on a 1- or 2-year interval basis. Thus, two
prediction intervals of 1 (T1) and 2 years (T2)
were formed.

• In the adolescent, the stage of somatic maturity
may influence the selection of the appliance, the
course of treatment and the mode of retention
after therapy.
• For the assessment of the status of the pubertal
growth period, longitudinal records of the body
height development (velocity growth curves)
have been recommended.

Landmarks
• Sh – highest point on peripheral border of
frontal sinus.
• Sl – lowest point on peripheral border of
frontal sinus.
• Perpendicular to the interconnecting line
(Sh-Sl), the maximum width of the frontal
sinus was assessed.

• Average yearly body height growth velocity
(mm/yr) was calculated.
• Bp (body height peak) = maximum body
growth velocity at puberty (used to test the
accuracy of prediction of pubertal stage as
assessed from frontal sinus development).

Somatic maturity prediction
• Frontal sinus growth velocity at puberty is
closely related to body height growth velocity.
• Well defined pubertal peak (Sp), on
average, occurs 1.4 years after the pubertal
body height peak (Bp).
• Males – average age at frontal sinus peak is
15.1 years.

Somatic maturity prediction
• Peak growth velocity in the frontal sinus of
atleast 1.3mm/yr is attained in 1 yr
observation.
• In 2 yr observation interval, a peak velocity in
the frontal sinus of atleast 1.2mm/yr is
attained.

Prediction procedure
• Frontal sinus growth velocity (Sv) in each
person was compared with T1 and
T2(threshold) values.
• If Sv is as high as or higher than T value (T1 or
T2), it may be expected that the frontal sinus
peak was reached during prediction interval.

Prediction procedure
• If the Sv is lower than the T-value, it cannot be
said whether the subject is pre peak or post
peak in frontal sinus growth.
• May be related to chronologic age (frontal
sinus peak at 15.1 years).

Relationship between mandibular canine
calcification stages and skeletal maturity.
-Sandra Cortinho, Peter H. Buschang.
AJODO:104:sept 1993.

• Handwrist radiographs and dental panoramic
radiographs of 200 boys and 215 girls were
assessed.

Stage D:
• Crown formation is complete down to C.E.
junction.
• Superior border of the pulp chamber in the
uniradicular teeth has a definite curved form
being concave towards cervical region.
• The projection of pulp horns, if present gives
outline shaped like an umbrella top.
• Beginning of root formation is seen in the form
of a spicule.

Canine development stage
• Stage D:

Stage E:
• The walls of the pulp chamber now form
straight lines whose continuity is broken by
the presence of the pulp horn, which is
larger than in the previous stage.
• The root length is less than the crown height.

Stage E

Stage F:
• The walls of the pulp chamber now form a
more or less an isosceles triangle. The apex
ends in a funnel shape.
• The root length is equal to or greater than
the crown height.

Stage F

Stage G
• The walls of the root canal are now
parallel and its apical end is still partially
open.

Stage H:
• The apical end of the root canal is completely
closed.
• The periodontal membrane has a uniform
width around the root and the apex.

Stage H

Results
• The initiation of spurt is indicated by canine
stage F i.e. the epiphysis of the 3rd and 5th middle
phalanges are equal in length to their diaphysis.
• No appearance of adductor sesamoid.
• The mean skeletal age for the presence of the
adductor sesamoid in the girls and the boys are
12.2 years and 13.2 years, respectively.

• In stage G, most show the adductor sesamoid.
• Capping of the diaphysis of the middle and distal
phalanges of the third finger, and capping of the
proximal phalanx of the fifth finger.
• Stage G coincides with the eruption of the canine
into the oral cavity, occurs approximately 1 year
before the PHV in boys, but only 5 months
before the PHV in girls.
• This may reflect hormonal changes which
accompany puberty.

• Thus, stage F indicates puberty.
• Stage G indicates peak height velocity
(PHV).
• The intermediate stage between stage F and
G should be used to identify the early stages
of the pubertal growth spurt.
• Canine development cannot and should not
be used as a sole criteria to predict
development landmarks.

Arcial growth prediction

Principle
• A normal mandible grows by superior-anterior
apposition vertically at the Ramus on a curve or arc
which is a segment formed from a circle.
• The radius of this circle is determined by using the
distance from Mental Protruberance to a point at the
forking of the stress lines at the terminus of the
oblique ridge on the medial side of the Ramus (Point
Eva).

Historical Review
• Hunter (1771) : Compared a series of dried
mandibles and concluded that, in order to attain
space for the development of permanent molar
teeth, the mandible must grow by posterior
apposition of the Ramus accompanied by anterior
Ramal resorption.

• Humprey (1866): Tied wires around the Mandibles
of pigs and showed that the wire became
embedded in the posterior margin and free in the
anterior area of the Ramus which seemed to be
verify the Hunter’s hypothesis.

• Brash (1924): Fed pigs the madder plant root which
contains the red stain alizarin and therefore labeled
appositional growth.
• He concluded that apposition occurred posteriorly
and superiorly on the Ramus of the growing pig
mandible.

THE COMPUTER (PRIMARY) STUDY
• Although the previous method was useful for
practical short term predictions, a method was
sought whereby mandibular growth patterns could
be identified with greater certainty.
• Next move towards improving the method was to
identify a “central core” cephalometrically as
external mandibular forms for reference are
unsuitable.

Locating a Cephalometric Central Core
Point Xi
• Located the following points on the Cephalogram :
R1 = deepest point on subcoronoid incisure
R2 = directly opposite R1 on the posterior border of the Ramus
R3 = at the depth of the sigmoid notch
R4 = a point directly inferior to R3 on the lower border of the Ramus

• By using these points, the centroid of the Ramus is
selected by forming a rectangle and connecting the
corners.
• Occlusal plane has a strong tendency to pass through
the Xi point.
• Xi also represents the entrance of the neuro trophic
bundle into the Mandible.

Suprapogonion
• Labeled as Pm for Protuberance Menti.
• It is a bony crest located at the antero-superior
contour of the Symphysis.
• On the cephalogram, it is the point selected on the
anterior border of the Symphysis between Point B
and Pogonion where the curvature changes from
concave to convex.
• Accepted as the most stable reference for anterior-
most basal bone in the mandible.
( Bjork )www.indiandentalacademy.com

Point DC
• A point selected in the centre of the neck of the Condyle where the Basion-Nasion
plane crosses it.
Condyle Axis
• Formed by connecting Points DC and Xi.
Corpus Axis
• Formed by joining Xi to Pm. www.indiandentalacademy.com

• By studying linear growth on these planes and the
form change as a change in the angulation between
the two, an interpretation could be gained regarding
the characteristics of growth in a given patient as well
as for groups with age and sex differences.

SAMPLE
• A five year growth study of the Mandible on the computer.
• Lateral and frontal cephalograms taken on 40 patients.
• Age: T1= 8 years (avg) +/- 2
T2= 13 years
• Sex: Males= 20
Females= 20
• Occlusion: Class I= 20
Class II= 20

RESULTS
• Samples were superimposed on the Corpus Axis and registered at
Xi point.
• Mandible was found to bend 0.5 each year.
• Lower facial height ( ANS-Xi-Pm) was found to be highly stable.
• It does not change during normal growth.

The sample are superimposed on the corpus axis and registered at
Xi point as the mandible was found to bend about one half degree
each year.

THE SECONDARY STUDY
• He sought a more detailed mechanism to explain
the development of the mandible.
• The fact that a bending was occurring in an
orderly fashion was recognized.
• Therefore, greater the magnitude of growth,
greater the bending.
• Apparently, a growth arc was operative.

• Experiments were undertaken to determine a method
by which the form and size of the mandible, after a 5
year growth interval, could be predicted with use of
only the first X-ray as a reference.
• The size increases and form alterations were available
from the previous study.

• The first arc was constructed in the Time 1 composite
through the three points :
Pm, Xi, Dc
• By extending this arc, the size increase was produced
but not enough bending was produced.
• The mandible became more obtuse than was the
actual behaviour.

• A second arc was made by joining the following
points:
1. tip of coronoid process
2. anterior border of ramus at its deepest curve
3. suprapogonoin
• The extension of this curve exhibited in the
segment of the circle too small in radius.
• Showed excessive bending of the mandible.

• Hence, the characteristics of typical growth had been
bracketed by the two arcs produced.
• Therefore, an arc was constructed bisecting these
previous two arcs.
• Established a halfway point between Xi and R1 points
and using the distance from this point to Pm as a
radius of a circle, an arc could be produced.

• The use of this arc bent the mandible by a fraction too
much.
• Additionally, a radius selected from this point would
increase with the size of the mandible and a changing
arc would result.
• Next, he thought that perhaps the stress lines of the
mandible might be useful.

• The mandible used for studying the stress lines was
850 years old.
• It had been weathered to a state of disintegration of
the interprismatic substance of the external cortical
bone.
• Hence, it clearly showed the stress lines in the outer
and inner plates.
• Hoped that these functional stress lines could yield
clues about mandibular development.

Stress lines on Lateral side
• There is convergence of stress lines at the
protuberance menti.
• Stress lines swing downward and then upward and
backward and outward through the external
oblique ridge
• An irregular gnarled area was present at the base of
the coronoid process as the stress seemed to divide
forward or backward in respect to condylar or
coronoid demands.

Stress lines on Medial side
• Greater forking was present than laterally.
• Stresses followed the Mylohyoid ridge upward into
a thick mass to terminate at a Y-shaped bony
prominence.

• Further study of several dozen mandibles
led to the observation of small, nutritive
foramina immediately superior to this area
medially.
• Hypothesized that this could be an
important mandibular growth area.

Locating point Eva
• A line from Xi point to Sigmoid notch is bisected and a parallel
point ( RR ) is selected on the anterior border of the Ramus.
• RR point is connected to Point R3 at the lower border of the
sigmoid notch. www.indiandentalacademy.com

• This line is crossed by a second line selected
from a point midway at the base of the coronoid
process to Xi point.
• The crossing of these two lines is called as Point
Eva.
• This point approximates the center of the upward
and forward quadrant of the Ramus.
• It also almost exactly coincides with the forking of
the stress lines on the internal and outer table of
the Ramus. www.indiandentalacademy.com

Locating point TR
• Point TR (true radius) is of equal distance from Point
Eva and Pm.
• The arc formed by joining Point Eva and Pm with
Point TR as the center of the circle represents the
true arc for the growth of the mandible.
• The point of intersection of the arc with the border
of the sigmoid notch is called as Mu.

• When the size increase of the mandible as determined by the
computer study was incrementally added to the arc at the
sigmoid notch, the predicted mandible was almost absolutely
correct in size and form when compared with the final
composite. www.indiandentalacademy.com

Growth Prediction
• Head films of a male patient, age 9 years, were
chosen.
• The patient was observed until almost 19 years of
age and no orthodontic treatment was rendered.
Step 1
• The amount of growth of the mandible on the arc
from the point Mu on the Sigmoid notch is 2.5 mm
each year.

• This was calculated from the previous study and
found to be an excellent population constant.
• Cutoff for growth= 14.5 years (females)
19 years (males)
• Apposition at the lower border of the symphysis of
the males occurs at about 1mm every 8 years.

Step 2
• Next, 20 longitudinal cases with a range of
duration of 5-12 years were measured.
• Study revealed that increases in condylar and
coronoid processes were different when
measured from Point Mu.
• The condylar and coronoid processes grow
upward and outward in a direction as a function
of the curve of the original arc.

• The k factor for coronoid process growth was 0.8 mm
per year.
• The condylar k factor was variable.
• Long condyles = 0.4 mm per year
Short and weak condyles = 0 mm
Average condyles = 0.2 mm per year.

Step 3
•In males, an addition of 0.2 mm per year is done
on the border of the mandible from the arc.
• No such addition is done in case of females.
• The gonial angle drifted posteriorly on the arc one
half the total increase in mandibular growth on
the arc.

Step 4
• The last step is to determine the space available
for the mandibular third molar at the anterior
border of the Ramus.
• With normal anatomic contouring, the coronoid
process is connected to RR point. It determines
the ramal width.
• Slightly below this point, the External oblique
ridge shows apposition of 0.4 mm per year.

PARENTAL DATA
According to studies by Suzuki and Takahama “Facial
growth prediction based on parental data”, there is high
level of significance of correlation between parents and
offsprings and siblings regarding craniofacial dimension.
• The craniofacial forms of children with a certain degree of
bone maturity were significantly correlated with those of
their parents.

• The genetic influence of parents of their
children appeared equal.
• Daughters seemed to be more affected
genetically than sons by their parents.
• The co-efficient of correlation of craniofacial
forms between children and their parents
increased from childhood to adulthood.

More precise prediction of individual growth
could be made by applying genetic data
obtained from similarities in craniofacial
characteristics between children and their
parents
• The face of the offspring often resembles that of
at least one of his or her parents.

• If the face of a young offspring resembles the
face of either parent, it will continue to
resemble that parent when the offspring
becomes an adult. That is, the phenotype of
facial appearance does not change with
growth.
• If the craniofacial type of an offspring
resembles that of the father or the mother in
the early growing stage, its adult craniofacial
type will be nearly like that of the same
parent. Thus the craniofacial form of offspring
can be predicted from parental data.

There is high correlation between the
craniofacial form of an offspring and that of
his or her parents. The relationship becomes
closer with growth, so it is better to use the
parental information than to use average
growth curves when the individual growth of a
child is to be determined.

CRANIOFACIAL TEMPLATES
FOR ORTHODONTIC ANALYSIS
In recent years, direct comparison of patients
with templates derived from various growth
studies has become a reliable method of
analysis, with the considerable advantage that
compensatory skeletal and dental deviations
within an individual can be observed directly.

The measurements for comparison with the norms
should have several characteristics:
• It should be useful clinically in differentiating
patients with skeletal and dental characteristics of
malocclusion.
• It should not be affected by the size of the patient.
• It should be unaffected by the age of the patient.

Templates exist in two forms :
• Schematic – it shows the changing position of
landmarks with age on a single template.
• Anatomically complete- it is a different one for
each age, they are convenient for direct visual
comparison of a patient with reference group while
accounting for age.

• While selecting a template, two things have to
be kept in mind:
– Patient’s physical size
– Developmental age

• Cranial base superimposition, which allows
the relationship of the maxilla and mandible
to the cranium to be evaluated.

• Second superimpostion is on the maximum
contour of the maxilla to evaluate the
relationship of the maxillary dentition to the
maxilla.

• The third superimposition is on the symphysis
of the mandible along the lower border, to
evaluate the relationship of the mandibular
dentition to the mandible.

Thank you
For more details please visit

Growth predictions /certified fixed orthodontic courses by Indian dental academy

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