2. Glass Ionomer Cement (GIC) is a dental restorative
material used in dentistry for filling teeth and luting
cements.
The early conventional glass-ionomer materials were
technique-sensitive,slow setting,opaque when set and
sensitive to both dessication and hydration during setting.
This led to premature surface deterioration.
3. Most of these problems have (more or less) been
solved in newer generations of glass-ionomer
cement. Setting has been accelerated and
hydration problems have been reduced.
However,unlike composites,their use in stressed
situations is still questionable.
The most common indication of the newer,heavily
filled,reduced particle size glass-ionomer cements
is in non-stress bearing build-ups,root
caries,tunnel restorations and long term
provisional restorations in primary and adult
dentitions.
4.
5. Resin modified glass-ionomer cements are
materials in which a hydrophilic polymerizing
resin is added to the glass-ionomer matrix.
The resin-modification of glass-ionomer cements,
introduced to obtain command set glass ionomer
cements, did not contribute to higher wear
resistance.
The admixed resin improves initial aesthetics,
tensile strength and fracture toughness.
Desiccation and hydration problems are reduced.
6. Resin-modified glass-ionomer cements set partly through
an acidbase reaction and a polymerization of the resin
component of the matrix.
The resin component can be light cured.
Another portion of the setting process involves the typical
acid base process between the filler and the poly-acid
matrix.
The hydrophilic character of the resin component also
contributes to osmotic swelling.
7. One of the factors affecting the strength of glass ionomers
is the chemical composition of the polymer matrix.
Most of the conventional glass ionomers contain
homopolymers or copolymers of unsaturated mono-, di -,
and tri – carboxylic acids. With these formulations, the
major problem lies in that the acrylic acid homo or
copolymers have –COOH groups which are directly
attached to the backbone and are closely oriented to each
other, resulting in a rigid polymeric structures.
It is presumed that strength or fracture resistance of the
ionomer material is weakened due to this steric hindrance.
8. So acrylic acid copolymers were modified with N – acryloyl
or N- methacryloyl amino acids, such as N –methacryloyl –
glutamic acid, providing a possible path to improved
conventional glass ionomers.
These newly formulated polyacids have flexible side chains
tethering the carboxylic acid groups at various distances
from the main chain polymer backbone, allowing for more
freedom and less steric hindrance when the carboxylic acid
groups are undergoing chemical reactions.
This type of modification has improved the fracture
toughness of the glass ionomer cement.
The copolymers with pendant amino acid residues have
also been developed for preparing visible light cure
formulations.
9.
10. Another step in merging the characteristics of resin-
based composites with those of traditional glass-
ionomer cements was the introduction of the poly-
acrylic acid modified composite resins, also called
compomers.
Compomers were intended as to optimally combine
the properties of glass-ionomers and resin-based
composites.
If regarded as a more or less temporary restorative,
compomers can replace resin-based composite in
anterior proximal restorations and have become in
many countries the material of first choice in
paediatric dentistry.
11. In almost all other applications, traditional
composites and glass-ionomer cements are
preferred because of greater strength and wear
resistance and better dimensional stability.
A disadvantage of compomers is that ease of
handling was obtained at the cost the established
specific properties of hybrid resin-based
composites and a proper glass-ionomer reaction.
12. GIOMER is a new group of direct restorative materials
and adhesives that offers aesthetics, handling and
physial properties of composite resins with added
benefits of high radiopacity, anti plaque effect,
fluoride release & recharge.
The GIOMER concept is based on the novel PRG(Pre
Reacted Glass-ionomer) technology, where special
PRG fillers are included in the resin matrix.
The initial GIOMER group of restorative materials
(BEAUTIFIL) contained the Surface Reaction Type
PRG fillers (S-PRG) and adhesive systems (FL-BOND)
contained the Full Reaction Type PRG fillers (F-PRG).
13. Among the GIOMER products, "BEAUTIFIL", an
aesthetic direct restorative material for anterior and
posterior teeth and "FL-BOND", a 2-step self-etching,
consisting of self etching primer and fluoride releasing
bonding agent have been clinically proven and
researched extensively worldwide.
Their excellent long-term clinical performance has
given GIOMER recognition as a unique group of direct
aesthetic restorative materials.
Properties of S-PRG Technology-
-Maintaining the property of multifunctional glass.
-High level of radiopacity.
-Properties of glass-ionomer (Fluoride release and
recharge,Biocompatibility).
-Long term clinical stability.
-Shade conformity (optical property)-Aesthetics close to natural
teeth.
-Resistance to wear of posterior teeth.
-Anti-plaque effect
14.
15. Both Giomer and Compomer are a true hybrid of two
compounds, Glass Ionomer and Composite.
The difference of Giomer from Compomer is, in Compomer
variable amount of unhydrated polyacrylic acid is added to the
resin matrix and the acid base reaction wont takes place until
water comes in contact with compomer.
The main disadvantage of COMPOMER is less amount of
Fluoride release and absence of Fluoride recharging ability.This
makes the GIOMER more preferable then compomer.
GIOMER uses PRG( Pre Reacted Glass ionomer )
TECHNOLOGY by which it differs from compomer, in giomer
the glass filler particles used are pre reacted with polyacrylic
acid.
18. Glass ionomer have been modified by addition of
filler particles ,to improve strength ,fracture
toughness & resistance to wear.
Silver alloy admix / miracle mix:-
This is made by mixing of spherical silver amalgam
alloy powder with glass ionomer powder.
Cerment:-
Bonding of silver particles to glass ionomer
particles by fusion through high temperature
sintering.
20. Unique processing of the glass component and
polyalkenoic acid(PAA) component.
Finely controlled particle size micronisation for
optimum properties.
Careful formulation for optimum
physical,aesthetic and handling properties.
It has ample wear resistance and all round strength
to easily rival composites and amalgams.
21. Designed to match the strength and durability of
amalgam.
Sustained high level of fluoride release.
Natural adhesion to tooth structure
Good biocompatibility with hard set and good
working time.
Minimal cavity preparation required.
Mercury and metal free.
Indications-
-Class III and class V cavities (particularly erosion lesions)
-Posterior cavities in deciduous teeth.
-Pits and fissure sealant.
22.
23. It is also known as Amalgomer CR or Posterior
Amalgomer.
Amalgomer CR is in a class of its own amongst
glass ionomers.
It uses Amalgomer Technology to exceed 300 MPa
compressive strength combined with unique
ceramic reinforcement for added durability and
high radiopacity.
24. ACTA wear tests indicate a much lower wear rate
than conventional GIC,compomers and most
composites.
Erosion rates and also very low as indicated by the
lactic acid jet erosion test specified in ISO 9917
(The Glass Ionomer narmative standard)
The all round strength of Amalgomer Technology
also gived it excellent resistance to fracture or
cracking and the high modulus allied to chemical
adhesion to the tooth struture ensures low
interfacial stresses.
Hence Amalgomer CR is well capable of
withstanding all the stresses of the oral
environment for long lasting restoration.
25. Class I and II cavities.
Repair of Amalgam restored teeth.
Base under amalgam and composite restorations.
All classes of cavity where radiopacity is a prime
requirement.
Core build up.
Long term temporary replacement for cusps.
Minimal intervention treatment.
ART technique.
Repair to crown margins.
26.
27. Since the development of glass ionomer cements nearly
three decades ago, these materials have found increasing
applications in clinical dentistry.
Clinical experience has defined the practical advantages
and disadvantages of glass ionomer cement system.
This has resulted in improved formulations and more
controlled techniques.
Of course it is difficult to produce an ideal material, but
with the current level of intensive research on glass
ionomers, the deficiencies that exist can be eliminated, or
at least reduced, resulting in an ever – improving range of
materials of this type.
28. Advances in Glass-ionomer cements
-Carel L. Davidson
Glass Ionomer Cement – The Different Generations
-Nagaraja Upadhya P and Kishore G.
(Department of Dental Materials,
Manipal College of Dental Sciences, Manipal)
Online Dental Journal-article on Giomer (Published in
Aug,2008)