Modern Restorative Materials

1. NAVODAYA DENTAL COLLEGE
DEPARTMENT OF PEDODONTICS
STAFF NAME – Dr VINOD KUMAR
Professor and Head of department
TOPIC NAME –Modern restorative materals

2. GLASS-METAL IONOMER
MIXTURES
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition
In 1957, Massler published an article about using a
restorative of amalgam powder mixed with zinc
phosphate cement for pulp capping.
In 1962, Mahler and Armen showed that adding amalgam
alloy to zinc phosphate cement improved the transverse
strength, solubility, and disintegration of the resulting
material compared with using zinc phosphate cement
alone.

3. In the early 1980s, prior to the introduction of
radiopaque glass ionomers, lucent glass ionomer
powders were mixed with amalgam powders to produce
glass-metal ionomer mixtures that are radiopaque yet
maintain many of the favorable properties of the glass
ionomers.
These restoratives are called admixtures. And, some
clinicians call this combination “miracle mix” and have
made metal-ionomer mixtures popular as core buildups,
bases, retrofills, endodontic sealers, and crown repairs.
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition

4. The major material disadvantage of the glassmetal
ionomer mixture is the difficulty of achieving a
homogeneous mix of silver and glass throughout the
restorative.
In addition, the metal particles are not well bonded to
the set material, which results in erosion and increased
wear as the poorly attached metal particles are plucked
from the surface.
Clinical problems also result from moisture
contamination during setting.
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition

5. CERAMIC-METAL GLASS
IONOMERS
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition
In 1987, the first cermet (ceramic + metal) glass
ionomer, Ketac-Silver® (ESPE), was introduced.
ESPE researchers McLean and Gasser developed these
ionomers filled with sintered metal and glass
compositions.
Their intention was to improve the bond between the
metal filler and the glass cement powder and produce a
material with better wear properties.
Using a silver-impregnated coating around the
aluminosilicate glass powder lowered the coefficient of
friction, thereby significantly improving abrasion
resistance.

6. Cermet ionomers are prepared by sintering (at 800°C)
compressed pellets made from a mixture of fine metal
powders and ion-leachable glass fillers.
The bond between these metals and glass particles
results in a seal that is similar to that of a
porcelainfused-to-metal restoration.
The resulting metalfused- to-glass filler particles can be
reacted with polyacid copolymers to form an ionomer
restorative.
The most suitable metals for these cermet ionomers are
gold and silver.
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition

7. RESIN-MODIFIED GLASS
IONOMERS
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition
Resin-modified glass-ionomer materials attempt to
combine the best properties of composite resins and
glass ionomers.
They have some cariostatic properties, a low thermal
expansion, and the hydrophilic qualities of the glass-
ionomer cements.
The polymerizing resin matrix of resin-modified glass
ionomers improves the fracture toughness, wear
resistance, and polish of these materials compared with
conventional glass ionomers.

8. Antonucci and co-workers introduced the lightcured
glass-ionomer cements in 1988. Vitrebond, the first
commercially viable cement of this type, was developed
by Mitra in 1989.
These early modified resin ionomers had two setting
mechanisms: a lightintiated polymerization reaction and
a glass ionomer acid–base reaction.
In 1992, Mitra added the first autocured resin
capabilities to resin-modified glass-ionomer cements.
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition

9. Classification by use
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition
There can be eight classes formed
1. Glass-ionomer luting cements used as luting agents.
They are autocured.
2. Glass-ionomer restoratives used as restorative
materials. The major difference between luting and
restorative glass ionomers is that the restorative is
available in more shades, has a higher filler load, and
has a much higher film thickness. They are autocured.
3. Glass-metal ionomer mixtures are intended for bases
and buildups. These are sometimes called admixtures.
They are autocured.

10. 4. Cermet-ionomers are ionomers containing metal-fused-to-glass
particles. Neither the glassmetal nor the cermet-ionomers are
tooth-colored. They are autocured.
5. Glass-ionomer liners are rapid-setting radiopaque materials for
dentin liners under composites and amalgams. They are light-
cured.
6. Glass-ionomer bases intended as bases under other restoratives.
7. Glass-ionomer sealants for sealing pits and fissures. They are
autocured.
8. Resin-modified glass ionomers include light- and dual-cured
glass ionomers.
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition

11. Advantages of glass ionomers
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition
Form a rigid substance on setting
Good fluoride release (bacteriostatic, inhibit caries)
Low exothermic reaction on setting
Less shrinkage than polymerizing resins
Coefficient of thermal expansion similar to dentin
No free monomers
Dimensional stability at high humidity
Filler–matrix chemical bonding
Resistant to micro-leakage
Non-irritating to pulp
Good marginal integrity
Adhere chemically to enamel and dentin in the presence of moisture
Rechargeable fluoride component
Good bonding to enamel and dentin
High compressive strength

12. Disadvantages
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth edition
• Susceptible to dehydration over lifetime
• Sensitivity to moisture at placement
• Poor abrasion resistance
• Average esthetics
• Less tensile strength than composites
• Technique sensitive powder-to-liquid ratio and mixing
• Less color-stable than resins
• Contraindicated for Class IV or other stressbearing
restorations
• Poor acid resistance

13. Resin-based Composite
Material
Dental composites, also called "white fillings", are a group
of restorative materials used in dentistry.
Composite typically consists of a resin-based matrix, such
as a bisphenol A-glycidyl methacrylate (BISGMA) resin
like urethane dimethacrylate (UDMA), and an inorganic
filler such as silica.
Compositions vary widely, with proprietary mixes of resins
forming the matrix, as well as engineered filler glasses and
glass ceramics.
The filler gives the composite wear resistance and
translucency.
A coupling agent such as silane is used to enhance thebond
between these two components.
An initiator package begins the polymerization reaction of
the resins when external energy (light/heat, etc.) is
applied.
Wikipedia

14. Composition of Composite
Resin
(Feilzer and Dauvillier, 2003; Gonçalves et al., 2010; Gonçalves et al., 2011).
Enamel and dentin are good examples of natural
composite materials as both consist of organic and
inorganic materials, predominately hydroxyapatite
crystals.
Enamel consists of 5% organic and 95% inorganic
materials, while dentine consists of 25% organic and
water and 75% inorganic material.
Like enamel and dentine, resin composite is mainly
composed of an organic phase (resin matrix) and an
inorganic or dispersed phase (filler particles).
In addition, resin composite also contains and another
component which is a coupling agent (interfacial
phase).

15. Hybrid resin composites
Most currently available commercial resin
composites are hybrid composites.
Hybrid composites contain more than one size of
filler particle in order to maximise filler loading
and result in better mechanical properties.
Macro-filler particles are interspersed with smaller
silica micro-filler particles.
These glass spheres are of the magnitude of
0.04μm (later 0.05 – 0.1μm).
(Jorgensen and Asmussen, 1978; Braem et al., 1989; Bayne et al., 1992; Venhoven et
al., 1996).

16. Nano-resin composites
(Sharma et al., 2010). (Ferracane, 2011).
More recently, developments in nanotechnology have
produced potentially clinically superior resin composites
for use in both aesthetic and load-bearing situations.
Nanotechnology permits the uses of nanoscale (1-
100nm) level of filler size. Thus microfilled composite
could have been called nanofilled composite, but they
were not due to lack of detection of nanotechnology at
that period.
Nanometre-sized filler particles and larger groups of
fused nano-particles (nano-clusters) are dispersed in a
resin matrix to produce a nanocomposite.

17. Combining individual particles and
clusters allows for increased filler
loading without increased viscosity
imparting improved physical properties
and good handling characteristics.
The material is highly polishable and
since nano-clusters will breakdown
under force as opposed to becoming
dislodged
(Sharma et al., 2010). (Ferracane, 2011).

18. http://www.slideshare.net/biancawilda/composite-resin

19. http://www.slideshare.net/biancawilda/composite-resin

20. Organically Modified Ceramics
(Ormocers) Restorative
Materials
Organically Modified Ceramic [Ormocers] is a hybrid
material which is made by special processing based on
nanoscale technology, mixing organic and inorganic
components at a nanoscopic scale rather than by
conventional means of physical mixing of different
component of a matrix.
Ormocers have been developed as an alternative to the
dimethacrylate based composites
The chemical structure of Ormocers is based on
organically modified alkoxides and functionalised
organic oligomers/polymers
Moszner and Salz, 2001

21. Silorane Restorative
Materials
Weinmann et al., 2005
The name silorane is derived from the combination of
its chemical building blocks siloxanes and oxiranes
The siloxane block acts like a backbone for the silorane
structure and also it improves the physical properties of
composite by providing hydrophobicity to the silorane
thus reducing the water sorption.
Moreover this hydrophobic nature tends to absorb less
stain from a normal daily diet.

22. Composition
Braem M. J., Davidson C. J., Lambrechts P., Vanherle G. (1994), In vitro flexural
fatigue
Filtek Silorane Posterior Restorative:
• Silorane resin
• Initiating system: camphorquinone, iodonium salt,
electron donor
• Quartz filler
• Yttrium fluoride
• Stabilizers
• Pigments

23. Silorane System Adhesive Bond:
• Hydrophobic dimethacrylate
• Phosphorylated methacrylates
• TEGDMA
• Silane-treated silica filler
• Initiators
• Stabilizers
Available in A2 , A3 , B2 , C2
Braem M. J., Davidson C. J., Lambrechts P., Vanherle G. (1994), In vitro flexural
fatigue

24. Compomers
A type of translucent hybrid dental resin which has the ben
efits of composites and of glass ionomers which are used fo
restorations of molars and cosmetic procedures
Introduced in1990s
Compomer is a polyacid-modified compositeresin.
Compomer is made predominantly from resin composite
(90%) with the addition of a polyacid-modified molecule
similar to that found in traditional GIC.
Compomers are initially light-cured, but subsequently
absorb water, allowing for an acid-based reaction to set the
polyacid-modified molecule.
They have normal adhesion to tooth structure and are
always attached with resin dentin bonding agents
Wikipedia ,Harry F. Albers