By
Dr. RASHID HASSAN
BDS(de’ Mont) MSc (QMUL.UK)
Hod Science of Dental Materials
Overview \
2
USES:
Class III & V cavities.
Luting agent.
Orthodontic bracket adhesives.
Pit and fissure sealants.
Liners and bases.
Core buildups.
3
GLASS IONOMER CEMENT
GLASS IONOMER CEMENT
Unique features
Biological adhesion with Enamel & Dentin.
Fluoride releasing ability.
Disadvantages
Low fracture toughness.
Low flexural strength.
Low wear resistance.
Relatively poor esthetics.
Surface roughness.
Poor polishability.
4
5
100000 NANOMETERS 25 ,400 ,000 NANOMETERS 6
Nano Technology
7
8
NANO TECHNOLOGY
(SIMPLEST EXAMPLE)
9
NANO TECHNOLOGY
(SIMPLEST EXAMPLE)
In 1959 Faynman postulated that
”we can someday
manipulate material at an atomic
scale, as there is always room at the
bottom”
10
NANO TECHNOLOGY
1 1
POWER
OF
NANO
SCALE
NANOTECHNOLOGY
Defects Defects are known to exist in
materials.
Inglis in 1912 showed how stress
changes around a defect.
12
Smaller scale = Smaller defects
SCANNING TUNNELING
MICROSCOPE
ATOMIC FPRCE
MICROSCOPE
13
MICROSCOPIC ANALYSIS OF
NANO MATERIALS
1 4
Tests Performed
15
MECHANICAL PROPERTIES
16
* Tancan Uysal etal ,2010, Oxford Journals,
Medicine,European Journal of Orthodontics.Volume
32, Issue 1,Pp. 78-82
Richard Van Noort, Introduction to Dental Materials, 2007.3rd Edition, Elsevier, P 142.
Range of
GIC
Shear Bond
Strength
(Mpa)
Compressive
Strength
(Mpa)
Tensile
Strength
(Mpa)
Nano
ionomers *
8.26 265 58
Conventional
GIC
4.3 202 16
THREE BODY WEAR TEST
17
Atomic Force Microscopy
(AFM)
International parameter
for measuring surface
roughness.
Range from angstroms to
100 microns.
NANO IONOMERS TOPOGRAPHIC
ANALYSIS
NANO IONOMERS TOPOGRAPHIC ANALYSIS
19
MICROSCOPIC ANALYSIS
20
NANO IONOMERS
INDICATIONS
Primary teeth restorations.
Small Class I, Class III and V.
Temporary restorations.
Filling defects and undercuts,
“Sandwich” technique.
Core build-ups.
21
STORAGE & USE
1. Shelf life at room temperature is 24 months.
2.Recommended storage 2-27 C (36-80 F)
3.The Ketac N100 system is to be used at room
temperature of approximately 21-24°C(70-75°F).
22
NANO IONOMERS
.
23
Future work
Investigating other mechanical
properties
Relevance With oral environment
Fluoride Recharge
Biochemical Stability
Dr. RASHID HASSAN
BDS(de’ Mont) MSc (QMUL.UK)
Hod Science of Dental Materials
FOR VIDEO LECTURES ON DENTAL MATERIALS
VISIT dmbydrrashid on Facebook