Tooth Colour Restorative Materials in Ped Dent

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Tooth colour restorative
materials in pediatric
dentistry

Contents
• Ideal characteristics of
restorative material
• Glass ionomer cements
• Resin based composite
material
• Ormocers
• Compomers
• Giomers

Ideal characteristics of restorative
materials

Kenneth J Anusavice. Phillips’ science of dental materials. 11 th edition. Elsevier. 2004.

Glass-ionomer cement
• Developed in Britain, and firstly described
by Alan Wilson and Brian Kent in 1972
• Conserve tooth structure, assist in
remineralization while maintaining appeal.
• ƒƒFormed from the reaction of an ion-leachable calcium alumino-silicate glass
powder and a poly-alkenoic acid.
• “Glass polyalkenoate cements”
• Types (1) Conventional
(2) Resin
Modified
Harry F. Albers. Tooth-colored
restoratives principles and
techniques. Ninth edition. 2002

Classification by use








Type I

Type II

Type III

Type IV

Type V

Type VI

Type VII –
command set
• Type VIII –
treatment
• Type IX

cements

Luting
Restorative
Liner/base
Pit & fissure sealant
Luting for orthodontic purpose
Core buildup material
High fluoride releasing
Atraumatic restorative
Pediatric Glass Ionomer

Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth
edition

Advantages of glassionomers









Form a rigid substance on setting
Good fluoride release (bacteriostatic, inhibit caries)
Coefficient of thermal expansion similar to dentin
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
• High compressive strength
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth
edition

Disadvantages







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
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth
edition

Composition of GIC

Kenneth J Anusavice. Phillips’
science of dental materials. 11th
edition. Elsevier. 2004.

CERAMIC-METAL GLASS IONOMERS
• In 1987, McLean and Gasser developed
the first cermet (ceramic + metal)
glass ionomer, Ketac-Silver® (ESPE),
was introduced.
• This improved abrasion resistance and
compressive strength
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth
edition

RESIN-MODIFIED GLASS IONOMERS
• 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.
Harry F. Albers. Tooth-colored restoratives principles and techniques. Ninth
edition

• Antonucci 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

luting
PROPERTY

VALUES

1.Setting time(min)

7.0

2.Film thickness(µm)

24

3.24 hr compressive strength(Mpa)

86

4.24 hr diametrical tensile
strength(Mpa)

6.2

5.Elastic modulus(Gpa)

7.3

6.Solubility in water(Wt%)

1.25

7.Pulp response

Mild to moderate
Kenneth J Anusavice. Phillips’
science of dental materials. 11th
edition. Elsevier. 2004.

12

Restorative cements
PROPERTY

GLASS
IONOMER II

CERMET

HYBRID
IONOMER

1.Compressive
strength(Mpa)

150

150

105

2.Diametrcal
tensile
strength(Mpa)

6.6

6.7

20

3.Knoop
hardness(KHN)

48

39

40

4.Pulp response

mild

mild

mild

Resin-based
Composite Material
• 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.
• The filler gives the composite wear resistance
and translucency.
• A coupling agent such as silane is used to
enhance the bond between these two
components.
• An initiator package begins the polymerization
reaction of the resins when external energy
(light/heat,
etc.) is applied.
Harry F. Albers. Tooth-colored restoratives principles and
techniques. Ninth edition. 2002

Composition
• Resin matrix – BisGMA , UDMA , TEGDMA
• Fillers - used in dental composites to provide
strengthening, increased stiffness , reduced
dimensional change when heated and cooled ,
reduced setting contraction , enhanced esthetics,
and improved handling. Quartz , silica , barium
glass
• Coupling agent - silanes
• Activator –initiator systems – camphoroquinone
• Inhibitors – butylated hydroxide toluedene
• Optical modifiers/coloring agents – titanium and
aluminum oxides
Kenneth J Anusavice. Phillips’
science of dental materials. 11th
edition. Elsevier. 2004.

15

ADVANTAGES
1. Strong and durable
2. Tooth colored
3. Single visit for fillings
4. Resists breaking
5. Maximum amount of
tooth preserved .
6. Does not corrode
Frequency of repair
or replacement is low

DISADVANTAGE
S
1. Tooth sensitivity
2. Technique
sensitive
3. Costs more than
dental amalgam
4. Shrinkage
Leakage over
time

Harry F. Albers. Tooth-colored
restoratives principles and
techniques. Ninth edition. 2002

16

Kenneth J Anusavice. Phillips’
science of dental materials. 11th
edition. Elsevier. 2004.

17

Kenneth J Anusavice. Phillips’
science of dental materials. 11th
edition. Elsevier. 2004.

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

• The organic constituent of Ormocers is
used for cross linking the network whilst
the inorganic component improves
mechanical properties and other
properties such as thermal and chemical
stability.
• Another advantage of these materials is
that the large size of the monomer
molecule minimises polymerisation
shrinkage.
Rosin et al 2002; Kournetas et al.,
2004 and wear (Lutz and Krejci,
2000; Manhart et al. 2002)

• In a recent study, Ormocer-based
material demonstrated the lowest
decrease in hardness following immersion
in solvent for a period of time compared
with dimethacrylate-based composites
and as a result it has been proved to be
more resistant to solvent degradation
than any other material tested

(Cavalcante et al., 2011).

Compomers
• A type of translucent hybrid dental resin which has the benefi
ts of composites and of glass ionomers which are used foresto
rations of molars and cosmetic procedures
• Introduced in 1990s
• Compomer is a polyacid-modified composite resin.
• 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 polyacidmodified molecule.
• They have normal adhesion to tooth structure and are always
attached with resin dentin bonding agents
Harry F. Albers. Tooth-colored
restoratives principles and
techniques. Ninth edition. 2002

• Consequently, the material shrinks, initially
due to polymerization contraction, and
expands subsequently as water is absorbed.
• The addition of a polyacid-modified
molecule makes the material more
hydrophilic.
• Compomers are, therefore, relatively easy
to handle and apt for preparation.
• A dentin-bonding agent is required for their
successful placement.
Harry F. Albers. Tooth-colored
restoratives principles and
techniques. Ninth edition. 2002

• Physically, their properties are similar
to those of a composite.
• The wear rates and fracture resistance
are less than for a composite.
• Compomers and composites have the
same advantages .
• Additional advantages of compomers
include fluoride release and ease of
handling.
Harry F. Albers. Tooth-colored
restoratives principles and
techniques. Ninth edition. 2002

Giomers

• The material unites the chemistries of composite and
GIC in an effort to combine the advantages of both
materials, whilst minimizing the limitations of each.
• Giomers are newly introduced hybrid aesthetic
restorative materials for dental restorative therapy.
• They are based on pre-reached glass-ionomer (PRG)
technology.
• Chemically, they consist of fluoroalumino silicate glass
reacted with polyalkenoic acid in water prior to
inclusion into the silica-filled urethane resin.
• Giomers contain both of the essential components of
glass-ionomer cements and resins but they cannot be
classified as compomers, in which a variable amount
of dehydrated polyalkeonic acid is incorporated in the
Kenneth
J Anusavice.
Phillips’
resin matrix and the
acid
does
not react with the glass
science of dental materials. 11
edition. Elsevier. 2004.
until water uptake occurs.
th

• Giomers can be subdivided into two distinct
groups of materials, namely those in which
the glass ionomer particles have been
surface reacted and those which have been
fully reacted.
– Surface pre-reacted glass ionomer giomers are
suitable for composite indications
– Fully pre-reacted glass ionomer giomers are
used in dentin adhesive systems, fissure
sealants, and as restorative material for
nonloaded-bearing areas
Kenneth J Anusavice. Phillips’
science of dental materials. 11th
edition. Elsevier. 2004.

References

• Kenneth J Anusavice. Phillips’ science of
dental materials. 11th edition. Elsevier.
2004.
• Harry F. Albers. Tooth-colored restoratives
principles and techniques. Ninth edition.
2002
• Manappallil Basic Dental materials 3 rd
Edition
• : "Where and When Is It Appropriate to
Place Monolithic vs. Layered
Restorations," Inside Dentistry, August
2012, Vol. 8, Issue 8, E. McLaren, R.
Margeas, N. Fahl.

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