3. INTRODUCTION
Composite resins are a class of mature and well
established restorative materials that have their
own indication in anterior and posterior teeth.
Dental composites have continued to evolve with
the development of smaller particle sizes, better
bonding systems, curing refinements and sealing
systems. Although composites are now well
accepted in general practice, the complex steps
involved have hindered their full success.
4. HISTORICAL DEVELOPMENT
During the first half of the 20th century, silicates
were the only tooth coloured esthetic material
available for cavity restoration.
Acrylic resins similar to those used for custom
impression trays and dentures replaced silicates
during the late 1940s and the early 1950s because of
their tooth like appearance , insolubility in oral fluids,
ease of manipulation and low cost.
5. In 1956, Dr. R.L. Bowen developed a polymer based on
dimethacrylate chemistry.
This polymer was generally known as Bis-GMA or
Bowen resin, was made up from the combination of
bisphenol – A and glycidyl methacrylate.
7. DEFINITIONSKINNER’S
A highly cross linked polymeric material reinforced by a
dispersion of amorphous silica, glass, crystalline or organic
resin filler particles and/or short fibers bonded to the matrix
by a coupling agent.
DCNA
A 3 dimensional combination of at least two chemically
different materials with a distinct interface separating the
components.
8. STURDEVANT
In materials and science word composite refers to
a solid formed from two or more distinct phases
that have been combined to produce properties
superior to or intermediate to those of individual
constituents.
9. INDICATIONS
Class I, II, III, IV, V, VI
core buildups
Sealants and preventive resin
restorations
Esthetic enhancement
procedures
Cements
Veneering metal
crowns/bridges
Temporary restorations
Periodontal splinting
Non carious lesions
Enamel hypoplasia
Composite inlays
Repair of old composite
restoration
Patients allergic to metals
15. STURDEVANTClassification of composites based on the filler particle
size
Megafill- in this one or two large glass inserts 0.5 to 2 mm
in size are placed into composites at points of occlusal
contact.
Macrofill- particle size range between 10 to 100 µm in
diameter
Midifill - particle size range between 1 to 10 µm in
diameter, also called traditional or conventional
composites.
Minifill - particle size range between 0.1 to 1 µm in
diameter
Microfill - particle size range between 0.01 to 0.1 µm
Nanofill - particle size range between 0.005 to 0.01 µm
18. According to CRAIG:
TYPE I:
Class 1 – Macrosized particles – 8-25µ
Class 2 – Mini size particles – 1-8µ
Class 3 – Micro size particles – 0.04-0.2µ
Class 4 – Blend of macro and micro – 0.04-10µ
TYPE II
Class 1: Macrosized 10-20µm (organic particles
in unreinforced resin matrix).
Class 2: Macrosize unreinforced particles 10-
20µ (organic in reinforced resin matrix 0.04-
0.2µ organic).
30. Filler particles are most commonly produced by
grinding or milling quartz or glasses to produce
particles ranging in size from 0.1-100um.
Submicron silica particles of colloidal size
(0.04um),referred to as microfillers, are obtained
by a pyrolytic or precipitation process.In these
processes a silicon compound is burned in an O2
and H2 atmosphere to form macromolecule
chains of SiO2.
32. Classification of fillersi): Quartz: It is made by grinding or milling quartz, was used in
early composites.it is chemically inert.
Because of its hardness it was difficult to grind to a finer size &
was difficult to polish, causes abrasion of opposing tooth
structure.
ii) SILICA :obtained by a pyrolytic or precipitation
process.Apart from reinforcing the composite ,it also helps in
high scattering and light transmission.
Forms of silica:Forms of silica:
- Pure silica.
- Fused silica.
- colloidal silica.
33. iii) GLASSES: Aluminosilicates & Borosilicates.provides
radiopacity.
Other fillers:
Tricalcium phosphate & Zirconium
dioxide.
Recently fluoridefluoride fillers like: Yittrium trifluoride &
Yitterbium trifluoride are introduced.
- to ensure acceptable esthetics of composite translucency
of fillers should be similar to tooth structure.
37. HEAT ,LIGHT AND SOME CHEMICALS CAUSES
DECOMPOSITION OF BP RESULTING IN FREE
RADICALS THAT INITIATE POLYMERISATION .
HENCE IT IS RECOMMENDED THAT COMPOSITE
SHOULD STORED IN COOL ,DARK ,CLEAN
ENVIORNMENT .
USES-RESTORATIONS AND LARGE FOUNDATION
STRUCTURES THAT ARE NOT EASILY CURED WITH A
LIGHT SOURCE.
38.
39. THESE COMPOUND ABSORBS
LIGHT(VISIBLE AND UV) AND
GENERATE FREE RADICALS .
FOR SYSTEM USING
ULTRAVIOLET LIGHT
INITATION BENZION ALKYL
ESTER IS USED AS
INITIATORS.
FOR SYSTEMS USING VISIBLE
LIGHT A DIAKETONE SUCH
AS CAMPHOROQUINONE
(APP.0.2%) IS USED .
CQ ABSORBS BLUE LIGHT
(400-500NM),PRODUCES AN
EXCITED STATE OF
CQ+AMINE FREE
RADICALS.
40. INHIBITORS
Butylated hydroxytoluene (BHT)-0.01%
4 –Methoxy phenol (PMP)
Extends storage life and provides sufficient working
time
THESE COMPOUNDS ARE USED IN AMOUNTS OF
0.1 % OR LESS
OPTICAL MODIFIERS
Pigments-metal oxides
Opacifiers-titanium dioxide & aluminum oxide-0.001-
0.007%
Darker shade & opacifier-thin layers
UV light absorbers
51. Nanofilled Composites
These particles are extremely small (0.005- 0.01 µm)
and virtually invisible.
Their particle size is below range of wavelength of light
and thus they do not absorb or scatter visible light.
Nanofiller offers means of incorporating
radiopacifiers that do not interfere with esthetic
properties
52. THANK YOU
“The world hates change, yet it is the only thing
that has brought progress.”
-Charles Kettering
53.
54. FLOWABLE
COMPOSITES
Created for special handling properties– Fluid
injectibility.
Introduced in 1996, theflowablecompositesare
characterized by thepresenceof filler particlesthat
haveaparticlesizesimilar to hybrid compositebut
thefiller content isreduced which resultsin
viscosity
They werelaunched to improvehandling
characteristicsof existing composites
57. PACKABLE COMPOSITES
Based on newly introduced concept called
PRIMM(Polymer rigid inorganic matrix material)
System consist of aresin and aceramic component
Filler phaseinstead of being incorporated areground
particlespresent asacontinuousnetwork of ceramic fibers
Fibers composed of alumina& silicawhich are
superficially fused to each other at specific sitesto
generateacontinuousnetwork of small components
58. Silanization of thefibrousnetwork isdoneby infiltration with
BiSGMA resin
Consistency of PRIMM based compositeissimilar to freshly
triturated massof amalgam
PROPERTIES
Inorganic filler 65-81 wt %
Compressivestrength 220-300 MPa
Flexural strength 85-100 MPa
Tensilestrength 40-45 MPa
Elastic modulus3-13 GPa
Depth of cure6 mm
59. Antibacterial Composites
Compositesthat offer antibacterial properties arepromising
sinceseveral studieshaveshown that agreater amount of
bacteriaand plaqueaccumulateon thesurfaceof resin
compositethan on thesurfaceof other restorativematerial /
enamel surface.
Imazato et al 1994 incorporated anon-releasing newly
synthesized monomer MDPB with anti-bacterial properties
into resin composites.
60. MDPB ismethacryloxy decyl pyridinium bromide. It was
found to beeffectiveagainst variousstreptococci
However, itsactivity against other important species in
plaqueformation likeActinomycesstill needsto be
investigated
Silver hasalso been added in compositesto makeit
antibacterial
61. NANOCOMPOSITES
Inorganic Phase– nanosized – 0.1 to 100 nm.
Increased overall filler level.
Areunableto scatter or absorb visiblelight.
Nanofillers - usually invisible and offer the
advantageof optical property improvement
-Mitraet al., 2003
62. ORMOCERS
“Organically Modified Ceramics.”
Chemically- MethacrylateSubstituted Alkosilanesie.,
Organic -Inorganic Copolymers.
Based on organically modified heteropolysiloxanes.
Filler particlesareincorporated into thiscross-
linked inorganic and organic network matrix.
63. PROPERTIES
Compressivestrength: 410 MPa
Filler Content: 77-80%
Polymerization shrinkage: 1.97 Vol. %
Elastic modulus: 13-14 GPa
Polish ability: high gloss
Color stability: no discoloration ISO 4049
64. COMPOMERSPolyacid modified resins:
Mc Lean & Nicho lso n defined it as:
“Materials that may contain either or both of the
essential components of a glass ionomer cement
but at levels insufficient to promote the acid-base
curing reaction in thedark.”
Compomer monomerscontain acidic functionalacidic functional
groupsgroupsthat can participatein an acid/base glass
ionomer reaction following polymerization of the
resin molecule
65. A resin polymerization takesplaceresin polymerization takesplacewith the compomers
after thematerial hasset completely. The glass-glass-
ionomer reaction(acid/base) may then occurionomer reaction(acid/base) may then occur in thepresence
of water. In thepresenceof water from theoral cavity, the
acid functional groups, which areattached to themonomer
units, and havenow becomepart of thepolymerized material
areableto react with thebase(glass) to stimulatetheglass
ionomer reaction. FluorideisreleasedFluorideisreleased asaresult of this
reaction.
66. Pastecontaining Ca, Al, F silicateglassfiller in
dimethacrylatemonomerswith acrylic acid like
molecules.
Set by polymerization & then delayed acid/basereaction.
Good strength, biocompatible, low solubility.
Havehigher wear than composite, lower F releasethan
conventional GIC.
67. INDICATIONS:INDICATIONS:
Sealing and filling of occlusal pitsand fissures.
Restoration of deciduousteeth.
Minimal cavity preparation or tunnel preparation
Asaliner - cariostatic action isrequired.
Core-build – up.
Repair of defectivemarginsin restorations.
ClassV repairs.
Erosion
Retrogradefiling materials
68. GIOMERSHybrid of GlassIonomers& composites.
Advantagesof both.
Resin based & Contain Pre-reacted Glass Ionomer
particles.
FlourosilicateGlass+ Polyacrlylic acid & resin.
Giomers employ the use of (PRG) technology to form a
stable phase of GIC in the restoration and are also
known as PRG composites
69. Giomersarelight polymerized and require bonding
system for adherenceto enamel and dentin. Thebonding
system currently availableisknown asReactmer bond
(Shofu Inc. Kyoto, Japan).
Reactmer bond istheglassionomer based,
tricurable, all-in-one, filled adhesivebased on PRG
technology and consistsof UDMA, HEMA, PRG filler,
fluoroaluminosilicate glass, acetone, water and initiator.
70. SMART COMPOSITES
Ivoclair introduced a material in 1998 named
Ariston pHC (pH control).
Releases Fluoride & Ca Hydroxide when the
pH in restoration in thematerial islessthan 5.5
71. Smart compositeswork based on thenewly developed
alkalineglassfiller which will reducesecondary caries
formation at themargin of arestoration by inhibiting
bacterial growth. Thisresultsin areduced
demineralization and abuffering of theacid produced by
cariesforming microorganisms
72. Composition
Thepasteconsistsof mixtureof different typesof
dimethacrylate(20.8 wt %),
Inorganic fillers Ba, Al and F silicateglassfiller (1 μm)
Ytterbium triflouride
Silicon dioxide
AlkalineCasilicateglass(1.6 μm) in dimethacrylate
monomers.
It isfilled 80% by weight and 60% by volume.
73. CEROMERS
Ceramic Optimised Resins
Laboratory processed inlays, onlays.
Somemanufacturers– with fiber reinforcement for
short span bridges
Three-dimensionally loaded fillersin a
polymer matrix of which two arefluoride
releasing
77. MODE OF SUPPLY
For chemical cure-
syringes/tubs
For light cure-
spills/syringe/compules
78. CURING
CHEMICAL ACTIVATION
cold curing or self curing
Advantages
Even polymerization-75%
Disadvantages
Oxygen inhibition
No control over Working time
79. LIGHT
ACTIVATION
UV light
Visible light
Advantages
Easy to use, single paste
Less porosity
Less sensitive to oxygen
Command polymerization
Colour stability, colors can be
optimized
Better mech properties
Setting time –faster cure
– Disadvantages
• Increments
• Time consuming
• Poor accessibility
• Variable exposure
• Sensitive to ambient light
• Shrinkage
• Ocular damage
• Cost
80. Comparison
Chemical Light cure
Polymerization is central Peripheral
Curing is one phase Is in increments
Sets within 45 seconds Sets only after light activation
No control over working time Working time under control
Shrinkage towards centre of bulk Shrinkage towards light source
Air may get incorporated Less chance of air entrapment
More wastage of material Less wastage
Not properly finished Better finish
81. DUAL CURING
2 light cure pastes-syringes/tubs
Combines chemical and light curing
Disadvantages- air inhibition,porosity
Use-cementation of bulky ceramic inlays
EXTRAORAL CURING
Use- a chemical or light cured composite used to
produce an inlay on a tooth or die
88. LED units
ADVANTAGES
Cordless,light weight
Long lasting
No heat
Moderate curing time
Quiet
DISADVANTAGES
New technology
Slower than PAC
Batteries must be recharged
Higher cost
Low intensity
Narrow emission spectrum
440-490 nm
peak at 470 nm
near absorption max activation
of camphoroquinone
efficient
89. First
generation
high cost
low
irradiance
< 300
mW/cm2
increase
exposure
time
Second
generation
Single large
surfaced emitting
LED chips
lower cost
higher irradiance
> 600 mW/cm2
similar to
halogen
High heat
production
Third
Generation
1 or more low-
powered chips
that emit a
second
frequency
90. Optical Safety
Do not look directly at light
Protection recommended
glasses
Shields
May impair ability
to match tooth shades
91. Degree of conversion
% of C-C double bonds that have been
converted to single bonds to form
polymeric resin
Strength, wear resistance
Avg 50-60%, light cure-44-75%
Cross linked , pendant, free groups
Factors
Light curing: more shrinkage stress
Staining
Sensitivity
Secondary caries
92. polymerization shrinkage
Value: 1- 4% , stress: 17MPa
Prevents bonding to dentin-
strength required
Causes stress to develop
Externally: interface of restoration
& tooth
Internally: between filler and resin
93. Factors affecting stress development
Restorative technique
Modulus of resin elasticity
Polymerization rate
Cavity configuration
94. Cavity configuration [C-FACTOR]
BONDED WALLS
UNBONDED WALLS
C=
During curing, shrinkage leaves the bonded
surfaces in a state of stress, while the free surfaces
relax some of the stresses by contracting inward
toward the bulk of the material.
Use of incremental/layering technique
95. Two walled cavity Three walled cavity
C=
2 Bonded
4 Unbonded
C-FACTORC-FACTOR 0.50.5
CAVITY CLASSCAVITY CLASS IVIV
C=
3Bonded
3Unbonded
C-FACTORC-FACTOR 11
CAVITY CLASSCAVITY CLASS IIIIII
96. Four walled cavity Five walled cavityFour walled cavity Five walled cavity
C=C=
C-FACTORC-FACTOR 22
CAVITY CLASSCAVITY CLASS IIII
4Bonded4Bonded
2Unbonded2Unbonded
C=C=
C-FACTORC-FACTOR 55
CAVITY CLASSCAVITY CLASSII
5Bonded5Bonded
1Unbonded1Unbonded
97. REDUCTION OF RESIDUAL STRESS
Reduction in vol contraction by alteration of chemistry
Low shrink monomers
Clinical techniques
Curing rate control
Incremental build-up
Resin based composite systems
Dentin-enamel adhesive systems
Using material which flows
Material with low modulus of elasticity
Introduction of air bubbles
104. Tooth preparationCONVENTIONAL
DESIGN
Conventional Tooth Preparation
are those typical for amalgam
restoration
walls in butt joint junction (90º)
with the restorative material
Indications-
i. Preparations located on root
surfaces.
ii. Moderate to large class I
or class II restorations.
105.
106. MODIFIED
Scooped out preparation
Modified preparations are
indicated for the initial
restoration of smaller,
cavitated, carious lesions
usually surrounded by
enamel & for correcting
enamel defects.
107. This design is indicated when
only proximal surface is
faulty with no lesion present
on the occlusal surface.
• BOX-ONLY •FACIAL/
LINGUAL SLOT
• Design for restoring
proximal lesions on
posterior teeth.
108. Shade selectionShade selection
Composite shade is selected by working with a clean,
moist tooth prior to placement of a rubber dam.
Shade selection should be
done prior to prolonged
drying of teeth because
dehydrated tooth becomes
lighter in shade as result of
decrease in translucency.
109. Samples from the shade guide should be applied parallel with
the tooth whose color is being matched, not in front of it (it
will appear lighter), and not behind it (it will appear darker)
Shade selected acc. to
manufactures shade guide or
VITA shade guide.
Natural light is preferable.
Shade tab is holded near the
teeth to be restored & is partially
covered with lip or operator thumb.
110. To choose accurate color - small amt. of selected
color shade material is placed on the tooth, in close
proximity to the area to be restored & cured.
Isolation of operating field
a) Rubber dam
b) Cotton rolls with or without retraction cord
111. RESTORATIVE TECHNIQUERESTORATIVE TECHNIQUE
1.1. Preliminary steps for enamel & dentin bonding:Preliminary steps for enamel & dentin bonding:
Both liquid & gels etchants are available(32 to 37%).
Acidetchingisdonefor15-30secs.
Followingthisithastobethoroughly
rinsedwithawatersprayfor5-15secs.
Laterthesurfaceshouldbedriedwith
airorcottonpellets.Theetchedenamel
112.
113.
114.
115. Bonding
Use low viscosity resin which will flow into etched
enamel pores & dentinal tubules to form resin tags.
Act as intermediary between tooth and composite.
Thebondingagentisappliedusingamicrobrush.
Themanufacturer'sinstructionsarefollowedregardingtheno.ofcoatstobeappliedandthecuringtime.(usually20secs
labiallyandlinguallyeach) 20 - 30
sec.
Apply ampleApply ample
amounts,amounts,
leaveleave
undisturbedundisturbed
RemoveRemove
solvent withsolvent with
air-syringeair-syringe
117. The continuous cure refers to a light-cure sequence
in which the light is on continuously.
There are four types of continuous curing:
uniform continuous cure, step cure, ramp cure, and
high-energy pulse . Continuous curing is conducted
with halogen, arc, and laser lamps.
The discontinuous cure is also called soft cure,
which commonly uses a pulse delay.
Distance from a tooth to initiate a cure, and then
moving it close to the restoration for the duration of
appropriate exposure.
118. In uniform continuous curing intensity is kept
uniform over the time
119. In step curing intensity is increased in sudden step over
the time.
120. Ramp curing is where the intensity continuously
increases over the time
121. In high energy pulse the high intensity is
kept for shorter exposure time.
122.
123. 3. Insertion of composite3. Insertion of composite
Can be inserted with the help of hand instruments or syringe
or guns.
Material is inserted in increments in thickness of 1-2mm
124. Different designs of increment placementDifferent designs of increment placement
1.Three increment design
one flat increment at gingival &
occlusal wall & two oblique
increments both at proximal
box occlusal box.
1st
increment thinner than 1.00mm.
2. Horizontal layering design
small increments placed
horizontally one above the
other, starting from gingival wall
to occlusal wall.
125. 3. Oblique layering design
Each increment is placed obliquely
starting from any sides & curing
is done from all three sides.
4. U-shaped layering design
At base, both gingival & occlusal
gingival, U-shaped increment is given
126. 5. Vertical layering techq.
Increments are placed in vertical
fashion starting from one wall
& carried on to another wall & curing
is done from behind the wall.
6. Layering techq. in the proximal box
& curing each increment by inserting
the fiber-optic microtip into composite.
128. REPAIR OF COMPOSITES
OLDER
RESTORATION
Etch, primer,
adhesive, composite
Bond strength- 50%
FRESHLY
POLYMERIZED
If not yet contoured
Directly place
composite
If contoured and
polished
Re-etch, adhesive,
composite
129. TUNNEL RESTORATIONS
Jinks in 1963 introduced this as a conservative
approach for CLASS II.
Hunt & Knight modified the technique
INDICATIONS
Pt. with high esthetic demand, low caries rate with
small proximal caries without involvement of the
marginal ridge.
130. CONTRAINDICATIONS
Large proximal caries involving marginal ridges.
Marginal Ridges under excess occlusal loads.
Difficulty in access
Proximal
Caries
TunnelTunnel
Prep.Prep.
Round burRound bur
GICGIC
placedplaced ComposiComposi
te overte over
GICGIC
131. ADVANTAGES
Marginal ridge is preserved
Reduced microleakage
Adjucent tooth preserved
DISADVANTAGES
Poor visibility & lack of caries removal
Marginal ridge may be undermined
Prep. may extend closer to pulp than desired
132. SANDWICH TECHNIQUE
Developed by McLean.
Laminate or Bilayed technique.
Large Class III, IV, V & Class I, II.
COMPOSITECOMPOSITE
GICGIC GIC
COMPOSITECOMPOSITE
133. In close sandwich the GIC is placed over pulpal floor and
axial wall then composite is placed and cured on the GIC
In open sandwich the GIC is placed on the gingival seat
and on that
composite is cured till
the occlusal level
134. ADVANTAGES
Favourable pulpal response due to biocompatibility of
GIC.
Fluoride release minimizes recurrent caries.
Less composite, less polymerisation shrinkage.
DISADVANTAGES
Time consuming.
Technique sensitive.
Adhesion of composite with GIC is a worry.
135. CONCLUSION
Composites have acquired a prominent place among the
filling materials employed in direct techniques. Their
considerable aesthetic possibilities give rise to a variety of
therapeutic indications, which continue to grow as a result
of the great versatility of the presentations offered.
Nonetheless, it should not be forgotten that they are
highly technique-sensitive, hence the need to control
certain aspects: correct indication, good isolation, choice
of the right composite for each situation, use of a good
procedure for bonding to the dental tissues and proper
curing are essential if satisfactory clinical results are to be
achieved.
136. REFERENCES…
Phillips’: Science of dental materials
Sturdevant : Art and science of operative dentistry
Vimal Sikri : Textbook of operative dentistry
Marzouk : Operative dentistry - modern theory and practice
Craig: Dental marterials
Charbeneau : Principles & practice of operative dentistry
Goldstein : Esthetics in dentistry
Hinweis der Redaktion
Fluoride Release & fluoride recharge of GIC
Excellent esthetics, easy polishability & biocompatibility.