Development of palate /certified fixed orthodontic courses by Indian dental academy

DEVELOPMENT OF
PALATE

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

FERTILIZATION

BLASTOCYST

MORULA

2 CELL STAGE

4 CELL STAGE

16 CELL STAGE


PRENATAL DEVELOPMENT
3 – 7 weeks

first 2 weeks

3

STAGES

GERMINAL

EMBRYONIC

8 wks – 9 mths

FETAL

3 WEEKS

4

5 WEEKS

WEEKS

6 WEEKS

7 WEEKS

IN FOCUS . . .

The normal …. at a glance.


The Hard Palate . . .

MID PALATINE ZONE
GLANDULAR RAPHE
INCISIVE PAPILLA
FATTY ZONE
RUGAE


Two sides of the
same coin . . .
NASAL SIDE

COLUMNAR CILIATED

ORAL SIDE

STRATIFIED SQUAMOUS


The Bony Palate . . .

HORIZONTAL PLATE
PALATINE PROCESS
PALATO MAXILLARY
INTERMAXILLARY
INTERPALATINE
F F.LESSER FORAMEN
.GREATER PALATINE
PREMAXILLA
INCISIVE PALATINE
OF PALATINE BONE
OF SUTURE
SUTURE
MAXILLA
SUTURE


Nerve Supply . . .
Blood

LESSER PALATINE
NASOPALATINE
GREATER PALATINE
ARTERY
NERVE
NERVE
NERVE


Soft Palate . . .

REDDISH MUCOSA
TASTE BUDS

NON KERATINISED


Soft Palate muscles . . .
Tensor veli palatini

Levator veli palatini
Palatoglossus
Palatopharyngeus
Musculus uvulae


Functions . . .

Separation of the two system
Swallowing
Breathing
Phonation
Mastication
Hearing
Taste


The Process of
Development . . .


PALATE DEVELOPMENT

PRIMARY

SECONDARY


PRIMARY PALATE

4 th week of intrauterine life

Fusion of medial nasal process
Forms intermaxillary segment

PRIMARY PALATE
FRONTAL VIEW

VENTRAL VIEW

Medial nasal
process

INTERMAXILLARY SEGMENT
PRIMARY PALATE

PRIMARY PALATE

Intermaxillary segment forms the primary palate
which becomes the future premaxilla,
bearing the four incisor teeth

SECONDARY PALATE

Starts at the 6 th week
Palatine shelves emerges laterally
from maxillary process
First descends vertically
downwards due to presence of tongue
Tongue drops, shelves ascends to a
horizontal position
Moves towards each other
Fuses with each other

Secondary palate . . .
FRONTAL SECTION
NASAL SEPTUM
MAXILLARY
PROCESS

PRIMITIVE MOUTH
TH
MOU

Stark compares . . .

O

UE
NG

T
Shelves fuse with each other,
With base of the shelves assume a
Tongue drops & nasal septum
Vertically downward orientation
& With primary palate anteriorly
Horizontal position. www.indiandentalacademy.com
of shelves.

BASSET HOUND

SECONDARY PALATE
VENTRAL VIEW

Coordinated formation of the primary palate,
secondary palate & nasal septum

SEM view of various stages
Downward shelf
orientation

PRIMARY
PALATE

7 WEEKS

Horizontal
orientation
8 WEEKS

Fused shelves

9 www.indiandentalacademy.com
WEEKS
22 WEEKS

Behind The Scene . . .


Shelf elevation . . . ?
Tongue depression . . .?
Shelves meet . . . ?
Shelf fusion . . . ?
Shelf position . . . ?

Shelf elevation . . . ?
Hydration & Polymerization
Hyaluronic acid
Seratonin & Acetylcholine release
Swelling of extra cellular matrix
Biosynthetic activity
Pushed by the tongue
Epithelial plug of external nares

Tongue depression . . . ?
Growth of Meckel’s cartilage
Myoneural activity of tongue
Maxilla – Cranium
Growth of head
Muscle traction
Swallowing & Hiccups
Withdrawal of head from heart

Shelves meet . . . ?
Rapid cell proliferation
Muscle segment homeobox
Bone morphogenic protein
Sonic hedge hog


Shelf fusion . . . ?
3 mechanisms

...

Necrosis of MES due to
lysosomal autolysis
Transformation of basal MEE
to mesenchyme
Migration of epithelial cells
nasally or orally

ADHESION OF SHELVES

SURFACE EPITHELIUM

BASAL EPITHELIUM

GLYCOPROTEIN RICH SEAM
MEDIAN EPITHELIAL COAT
BEFORE

24-36 HOURS - DNA SYNTHESIS STOPS

EPITHELIAL - MESENCHYMAL
TRANSFORMATION

II

I
TßR

TßR

Serine – Threonine
Kinases
Indispensable

TGF-ß
Betaglycan

III

Direct modulator

TßR

II

TGF-ß3
I

TGF-ß3

II

I

III
TGF-ß3

TGF-ß3

III

III

III

III
TGF-ß3 I

II

II

I

III

TGF-ß3

III III

I

TGF-ß3
I

III

II

I

II

II

I

III

TGF-ß3

TGF-ß3

III

I

TGF-ß3

I

II

I

III

II

III

IIII

I
TGF-ß3

I

II

II

II

III

I
TGF-ß3
I

III

II

III

II

I

II

III
III

II

III

SMAD PROTEINS

I

VERTICAL POSITION

HORIZONTAL POSITION
WITH MEE

HORIZONTAL POSITION
WITHOUT MEE

Shelf position . . . ?
Growth of the mandible
Swallowing of amniotic
fluid


Back to basics . . .


Origin of mesenchyme . . .
Neurulution
From mid &
hindbrain
into branchial
arches
Pluripotent Cells
Facial mesenchyme
Homeobox genes

Differentiates . . .
OSTEOBLASTS
MYOBLASTS

Bone formation
Muscle development

HAEMOCYTOBLASTS
LYMPHOBLASTS

Blood vessels
Lymphoid tissue


Muscle development of
soft palate…


Tensor Veli Palatini 40 days
Palatopharyngeous 45 Days
Levator Veli Palatini 8th week
Palatoglossus
Uvular

9th week
11 week
th


Origin….

Levator Veli Palatini Palatopharyngeus
&

Palatoglossus
Tensor Uvular
Veli Palatini

Ossification of Palate …


INTRAMEMBRANOUS OSSIFICATION
LOOSE MESENCHYME

COLLAGEN FIBRES

MESENCHYMAL CONDENSATION

COLLAGEN
FIBRE
OSTEOID
BUNDLES
GELATINOUS
MATRIX

OSTEOBLASTS

OSTEOCYTES

OSSIFICATION OF PALATE
At end of 7th week . . .
At the junction of vertical plate & horizontal plate
Tiny cresent places antero-posteriorly
with concavity towards medial
Extends upward to form vertical plate
& medialward to form horizontal plate

During the 8th week . . .
spreads backward to form
pyramidal process
downwards to form
tuberosity


At the 9th week . . .
the two branches of the pyramidal process
are widely seperated for internal pterygoid plate
vertical plate is at 45°
later stages at right angles to the
horizontal plate

In the 10th week . . .
the sphenoidal & orbital
process develops
at the junction bone extends
forwards & overlaps
maxillary bone
vertical plate – fan
horizontal plate – www.indiandentalacademy.com
pyramidal

Dimensions . . .
Horizontal more than vertical- fetal
Equal in length – at birth
Vertical more than horizontal – after birth


Mesenchymal condensation . . .
Reorientation of the Golgi bodies
Fibronectin for cluster formation
Polysaccharide prevents aggregation
Hyaluronidase breaks down
inhibitors

Sutures . . .


Sutures . . .
Site of cellular proliferation &
fibre formation
Appositional osteogenesis
Growth occurs as compensation
to separating forces
Alternating oscillatory movement
Responds towww.indiandentalacademy.com and tension
pressure

Mid palatal suture . . .
Plane or butt-end type
First evident at 10 ½ weeks i.u
Growth ceases between
1 and 2 years
Obliteration starts in
adolescence
Complete fusion rare until

INFANCY


Y

CHILDHOOD


T

ADOLESENCE

HIGHLYwww.indiandentalacademy.com
INTERDIGITATED

Ossifying centres . . .


DISPUTES IN OSSIFYING
CENTRES

Kölliker

One centre

Albrecht

Two centre


More disputes . . .

Callender

–

no centre of

Schwink
Piersol
Rambaud & Renault

1

its own

centre

3 centres
Frasetto 5 centres
Jarmer

–

–

Fawcett

–

Prevomerine

centre

Essential facts . . .
Premaxilla – 8 weeks
Palatine bone – 9 weeks

The centers fuse into a single mass
before the 25 mm stage (CRL)
Premaxilla contributes to anterior
nasal process after fusion

GROWTH


CRANIAL Vs FACIAL GROWTH

POSTNATAL – MORE FACIAL THAN CRANIAL

REMODELING
Vs

DISPLACEMENT


REMODELING
Resorption & deposition
Genic tissues
Inferior direction
Resorption on oral side
& deposition on nasal side
Relocation of the palate

REMODELING
Changes bone size
Relocates bone
Shapes the bone
Fine tune fitting of bone
Adapts the bone

FETAL SKULL

ADULT SKULL

Relocation
Increase in vertical dimension

REMODELING

Resorption

Nasal side
Oral side

Deposition

Downwards

REMODELING
Resorption
outer side
Deposition
inner side

ds
ar
ow d
t
g en
in r
ov ide
M W

Change in position
Change in size

V

rin
P

ple
ci

Palate becomes wider

DISPLACEMENT
Physical movement as a whole
Expansive force of soft tissues
Simultaneously remodels
Primary / Secondary
Forwards & Downwards

DISPLACEMENT

1

2
3

REMODELLING
DISPLACEMENT


GROWTH ROTATION
Compensatory
remodeling
rotation
Fields
reversed

Displacement
rotation

Drift . . .
drift is the movement of bone in space by virtue of
apposition on one side of a cortex or surface & resorption
on the other
palatal drift - classic example
nasal floor – resorptive &
roof of mouth - depository


VERTICAL DRIFT or ERUPTION
Takes place in addition to eruption
Occurs by resorption & deposition
periodontal connective tissue membrane

Provide adjustments for palatal
displacement rotations to level
the occlusal plane

COUNTERPART PRINCIPLE
growth of any given facial or cranial part
relates specifically to other structural &
geometric counterparts
if each regional part & its counterpart enlarge
to the same extent , balanced growth results


COUNTERPART PRINCIPLE

Anterior cranial
palate
fossa

Palate

Maxillary base

THEORIES OF GROWTH
SICHER’S THEORY

SCOTT’S THEORY

MOSS THEORY

Sicher’s Sutural dominance theory . . .

Reasons for failure . . .
Growth site

Vs

Growth centre

After transplantation
tissue did not grow
Suture are areas that react
to stimulus


Compare man . . .
. . . & his best friend !

...A

Axis .
Maxillo mandibular apparatus . . .
Cranium . . .
Less
Big prominent
Vertical
More
Smallprominent
Horizontal

Human skull

Dog skull

Striking differences . . .

Reasonable hypothesis . . .

Feature
s

Pronograde – four footed
Olfactory sense – the first sense !
Tactile sensation of the snout
Eating style
Other functions – tactile, holding, breaking, fighting etc.


Reasonable hypothesis . . .
Plantigrade – two footed
Well developed brain – frontal lobe
Liberty of limb movements
Eating style & defence
Cooked food – weaker muscles
Speech – broader arches ,forward chin

Feature
s

Evolution of Palate . . .
d
ape
- sh

UA. Afarensis

3

7

4

DEEP . . .
Homo Erectus

H.Neanderthalensis
12

P.Robustus

P.Boisie

A. Africanus

14

SHALLOW . . . for speech.

8

Homo sapiens
15

c
boli
a
Par

Foramen . . .
Constant remodeling throughout life
Decreases in size – physiological or pathological
contents are not affected in physiologic change
compressed in pathologic conditions
eg.cervical stenosis (intervertebral foramen)
appears to change in position due to changes in
neighboring structures
eg. Mental foramen

The debated Premaxilla . . .


PARTICIPANTS . . .

Separate . . .

VERSALIUS 1543
COLUMBUS 1559
FALLOPIUS 1561
CAMPER 1778
KOLLIKER 1882
FAWCETT 1911
ALBINUS 1746

Fused . .
WOODJONES 1929
.
LAWRENCE 1838

ROUSSEAU 1858 - 59

GOETHE 1786
KOSENMUELLER 1804


Premaxilla . . . A Problemaxilla?

Separate . .
Suture line
- Fetal

Fused . .
No suture line
- Adult

Suture on palate

Ossification defect

Ossification time Later fuse
All mammals

Humans exception


BAT

AUSTRALOPITHECUS
AFARENSIS

PE
A

-

CHIMPANZEE

AUSTRALOPITHECUS
AFRICANUS

GORILLA

HOMO SAPIENS

E
K
LI

3RD BRANCH

4TH BRANCH


15TH BRANCH

The difference of opinions . .
Separate ossification centres

Maxillary bone grows & spreads
over the facial surface of
premaxilla

No separate centre for premaxill
c – shaped maxillary centre

Convincing Proof . . .
Histological evidence . . .

Distinction between calcified bone
of maxilla and osteoid of the
premaxilla


Premaxilla . . . Problemaxilla?

The argument continues . . . . .

Dimensional changes . . .


CHANGES IN UTERUS
7 - 18 WEEKS

4 MONTHS

Length increases Width increases

CHANGES OUT OF UTERUS
AT BIRTH

Equal

POST NATAL

Length increases


The factors influencing. . .


Genetics . . .
IGF-II R / TGF-ß2 / cdK4
- Break In circuit
TGF –ALPHA A2
MUTATION OF OSR-2 & TBX22
GENE FOR GAD67

Environmental . . .
DRUGS
Corticosteroids
Anticonvulsants
Benzodiazepines
Methotrexate
Thalidomide
Phenobarbitones

HABITS
Smoking –

Maternal smoking
leads to cleft

Thumb sucking
Mouth breathing

- leads to narrowing of palate

DIETARY AGENTS
Vitamin A
Folate

INVESTIGATIONS
Radiation
CVS testing

L
GU

F

AR
W

CVS TEST
( CARDIOVASCULAR SYSTEM ? )
(CHORIONIC VILLI SAMPLING)

Detects chromosomal abnormalities
Done at 10 – 12 weeks of
pregnancy
The sample is removed
by suction
Risk of miscarriage

The abnormalities . . .


CLEFT PALATE

CROUZAN’S
PIERRE ROBIN
TREACHER COLLINS
SPRENGEL’S
MARFAN’S
APERTS

TREACHERROBINSYNDROME
PIERRE COLLINS’ SYNDROME
KLIPPEL FEILSYNDROME
CROUZON’SSYNDROME
MARFAN’S SYNDROME
DOWN’S SYNDROME
APERT’S
SYNDROME

Epstein’s pearls
Bohn’s nodules
Dental lamina cysts
Nasopalatine duct cyst
Torus platinus

. . .of soft Palate
muscle hypoplasia of
musculus uvulae
Paralysis


Orthodontic
perspectives….

Occlusion
Landmark in cephalometrics
Spongy bone
Nasorespiratory function
Mid Palatal suture
Onplants
Support www.indiandentalacademy.com
baseplate

Concluding . . .

“If the rate of growth of the first month
of embryonic life were to be maintained
until adulthood, the resultant individual
would be 1,28,350 to the 1,100 power of
light years in length.”
-Robert Bean
( Anatomist)

4 years . . .

6 years . . .

Adult . . .


Thank you . . .

For the patience!

Development of palate /certified fixed orthodontic courses by Indian dental academy

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