ENAMEL HYPOPLASIA
Introduction enamel
•Enamel formation is called Amelogenesis and its
started from cusps
• Origin: ectoderm
• Thickness:
• (incisors2mm __premolars 2.3_2.5& molars
2.5.3mm)
• Chemical composition: non organic 97% organic 3%
Definition of enamel
Characteristic of enamel
4.
CHARACTERISTIC OF
ENAMEL
• Enamelis the hardest substance of
the human body
• Enamel is a rigid,strong and brittle
• (high elastic modulus, high
compressive strength, and low tensile
strength)
• Dentin is more flexible, strong and
resilient (low elastic modulus, high
compressive strength, and high tensile
strength
5.
CHARACTERISTIC OF
ENAMEL
Intransverse section have a rounded
head or body section and a tail section
Rounded head(5 µm) tail(5 µm long)
The rods orientation
The rods number in tooth
Enamel rod diameter : 4 µm_8 µm
Composed of millions of enamel rods or
Prisma
6.
• enamel prismare made millions of
small, elongated apatite crystallite
• The crystallites are tightly packed in a
distinct pattern of orientation that
gives strength and structural identity
to the enamel prisms
• average length(160 nm )and average
width 20—40 nm
• Each apatite crystallite is composed of
thousands of unit cells
A
P
A
T
I
T
E
C
R
Y
S
T
A
L
L
I
T
E
S
GNARLED ENAMEL
• Gnarledenamel consists of bundles of enamel rods
which entwine in an irregular manner with other
group of rods, finally taking a twisted and irregular
path towards the tooth surface
• Gnarled enamel is not subject to fracture as much
as a regular enamel
development Stage
• Formationstage
• Calcification stage
• Maturation stage
• supports masticatory forces
• Mainly responsible for aesthetics
• Protects the underlying dentin and pulp.
Function of enamel
Functions & development Stage of enamel
Shafer’s textbook oforal
pathology
⦿ Calcium sucrose
phosphate gel- It involves
cleaning of the affected teeth
with pumice and glycerin and
rinsing with water and applying
37% phosphoric acid for 1.5-2
minutes. This treatment is
repeated , followed by
application of 2% sodium fluoride
for 4 minutes. Finally a thick
layer of calcium sucrose gel is
placed on the affected teeth .
The patient is instructed not to
eat anything or rinse for 30
minutes. It improves the colour
of the teeth.