2. Introduction
History
Definition
Indication and contraindication
Advantages and disadvantages
Classification
Composition
Mode of supply
Polymerization of composite
Properties of composite
journal review
Conclusion
3. The search of beauty can be traced to earliest
civilization.
Dental art has long been a part of the quest to
enhance the esthetics of teeth and mouth.
The constant desire of dental profession to
achieve a natural appearance has led to
development of various tooth colored materials,
one among them being dental composites
4. In the past, teeth were most commonly repaired with amalgam
(silver) fillings or gold restorations.
Teeth can be restored with a more aesthetic and natural
appearance
Tooth colored restorative materials have increasingly been used
to replace missing tooth structure and to modify tooth color and
contour, thus enhancing facial esthetics.
The simplest form of 'white filling' is technically called a
Composite.
5. 1855-vulcanite/ebonite
1868-John Wesley Hyatt- “celluloid”
1878-Thomas Fletcher – Silicate cement
1937-Dr Walter Wright-methyl methacrylate resin (acrylic resins)
1955 Michael Buonocore
1962 Dr Rafael Bowen – BisGMA
1972- Light Curing
1976 - Microfilled Composites
6. 1981 Hybrid composites
1991 – Beta quartz inserts
1995 – Compomer was introduced to improve the handling
and fluoride release.
1996 – Flowable composite; ceromer
1997 – Packable composite
1998 – Ormocers; ion-releasing composites; fiber –reinforced
composites
1999 – Single crystal-modified composites
2000-nanofill composites
7. By Anusavice
Composite – in material science, a solid formed from
two or more distinct phases that have been combined to
produce properties superior to or intermediate to those
of the individual constituents.
Dental composite is defined as 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 .
8. Class III, IV, V, VI
Core buildups
Esthetic enhancement procedures
Luting Cements
Temporary restorations
Periodontal splinting
Non-carious lesions
Enamel hypoplasia
Repair of old composite /ceramic restorations
Patients allergic to metals
10. Esthetics
Conservation of tooth structure
Less complex when preparing the tooth
Insulation to pulp
Used almost universally
Bonded to tooth structure
Repairable
No corrosion
12. 1. Skinner’s classification (10th edition) (mean particle size of major filler)
Traditional composites (Macrofilled) 8-12m
Small particle filled composite – 1-5m
Microfilled composite – 0.04 – 0.4 m
Hybrid composite – 0.6 – 1 m
13. Based on range of filler particle size
Megafill-β quartz , large size
Macrofill – 10-100 m
Midifill – 1-10 m
Minifill – 0.1-1 m
Microfill – 0.01-0.1 m
Nanofill – 0.005-0.01 m
14. Based on method of curing
Chemical curing
Light curing
UV light
Visible light
Dual cure
15. Based on consistency
Light body – Flowable composite
Medium body – Homogeneous microfills, macrofills
and midifills
Heavy body – Packable hybrid minifills
17. PRINCIPAL MONOMERS
◦ BIS-GMA-aromatic-1962-”BOWEN’S RESIN”
◦ Modified BIS-GMA
◦ UDMA(urethane dimethacrylate)- 1974 (Foster and Walker)
DILUENT MONOMERS
◦ TEGDMA(Triethylene glycol dimethacrylate)-aliphatic
◦ UDMA
NEW MONOMERS
18. Bis-GMA structure –
The bis-phenol A nucleus:
Terminal methacrylate groups –
Hydroxyl groups –
19. To overcome the high viscosity of Bis-GMA;
diluent was added
Diluent is any fluid methacrylate – TEGDMA
Ratio of Bis-GMA to TEGDMA – 3:1
Functions of the diluent –
Reduce the viscosity
Results in higher filler loading.
Results in higher degree of conversion.
Increase the number of cross-linking
reactions.
20. Benefits
Reinforcement of matrix resin resulting in increased
hardness, strength and decreased wear.
Reduction in polymerization shrinkage.
Reduction in thermal contraction and expansion.
Improved workability by increasing the viscosity.
Reduction in water sorption.
Increased radiopacity and diagnostic sensitivity through
the incorporation of strontium (Sr) and barium (Ba) glass
and other heavy metal compounds that absorb X-rays.
Contribute to esthetics.
21. Materials used for fillers:-
Type of glass
Quartz, silica, barium glass
22. Filler loading
Between 30 and 70 volume% or 50 to 85 wt% of a
composite.
Filler surface area
50-400 m2/gm
23. Essential for bonding of fillers to the resin matrix.
Functions:-
Bind filler particles to resin.
Allow more flexible polymer matrix to transfer stresses to the higher
modulus (more stiffer & stronger) filler particles
Impart improved physical & mechanical properties
Inhibit leaching by preventing water from penetrating along the resin-
filler interface.
Types :-
Organosilanes – γ-methacryloxypropyl trimethoxysilane (MPS).(most
commonly used)
Titanates.
Zirconates
24. Chemically activated
supplied as two pastes
Benzoyl peroxide initiator (universal paste)
Aromatic tertiary amine activator (N,N, dimethyl-p-toluidine)(catalyst paste)
p-toluidine sulfinic acid
Light activated
supplied as single paste contained in a light proof syringe.
Camphorquinone -0.2%-1%( photosensitizer)-Absorbs blue light with
wavelength between 400 and 500 nm
Organic aliphatic amine –dimetylaminoethyl methacrylate (DMAEMA)-0.15%,
ethyl-4-dimethylaminobenzoate (EDMAB), or N,N-cyanoethyl- methylaniline
(CEMA)
25. “Butylated hydroxytoluine” (BHT), which is used in
concentration of 0.01 wt%. inhibitors have two functions –
They extend the storage life time for all resins
They ensure sufficient working time
Optical modifiers
To match the appearance of teeth
commonly titanium dioxide and aluminum oxides are added as
opacifiers in minute amounts – 0.001 to 0.007 wt%.
27. Also called cold curing or self curing.
Initiated by mixing two pastes just before use.
Advantages –
◦ Even polymerization throughout the restoration to maximum
75%
Disadvantages –
Impossible to avoid incorporation of air into the mix forms
pores and weakens the structure.
Oxygen inhibition of polymerization during curing
No control over the working time
Both insertion and contouring must be completed quickly once
the resin components are mixed and placed into the cavity
Often discolors after 3-5 yrs of intraoral service.
28. Developed to overcome the problems of chemical
activation.
Light curable composites are supplied as a single paste
system.
Camphorquinone (CQ) is photosensitizer - absorbs blue
light with wavelengths between 400 and 500nm
Amine activator is Dimethylaminoethylmathacrylate
(DMAEMA) in case of visible light and
Benzoylmethylether in case of UV light polymerization
29. Advantages –
Easy to use, single paste system
Less porosity
Color stability
Command polymerization
Allow operator to complete insertion and contouring before
curing is initiated
They are not as sensitive to oxygen inhibition as the chemical
cured systems
Better mechanical properties
Setting time – faster cure; an exposure of 40 seconds or less is
required to light cure a 2mm thick layer.
30. Disadvantages –
They must be applied incrementally when the bulk exceeds approx. 2 – 3mm
Limited depth of light penetration
Time consuming
Relatively poor accessibility in certain posterior and interproximal locations
Variable exposure times because of shade differences, resulting in longer exposure
times for darker shades and/or increased opacity
Sensitivity to room illumination – leads to formation of a skin or crust when an
opened tube is exposed too long to room light.
light curing unit is expensive
Shrinkage towards light source
Ocular damage – can cause retinal damage if one looks directly at the beam.
31. 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
32. Consists of two light curable pastes, one containing
benzoyl peroxide and the other paste containing the
aromatic tertiary amine.
When these two pastes are mixed and then exposed to
light, light curing is promoted by the amine/CQ
combination and the chemical curing is promoted by
the amine/BP interaction
33. INDICATIONS
Any situation that doesn’t allow sufficient light
penetration to produce adequate monomer
conversion.
DISADVANTAGES
Air inhibition and porosity.
36. Quartz-tungsten halogen lamps:-
Have a quartz bulb with a tungsten filament that
irradiates both UV and white light that must be
filtered to remove heat and all wavelengths
except those in the violet-blue range (~400 to
500 nm)
Typically, the intensity ranges from 400 to 800
Mw/ cm2
Wavelength varies among the units from 450 to
490nm
A typical resin composite requires an energy
density of 16J/cm2 (400 mW/cm2 X 40 seconds
=16,000mWs/ cm2) for polymerization.
37. Advantages of the QTH:-
◦ Cost is less than the other light systems
◦ They generate little or no heat
◦ They are time proven
Disadvantages of the QTH
They have a slower cure time (about 15 sec) than PAC
lights (about 3 sec) or some LED lights (a range of 10 to 20
sec)
Most devices must be plugged into the house electricity
The units are relatively large and cumbersome
The bulbs decrease in output over a period of time
38. Contain two tungsten electrodes
seperated by a small gap in which a
large voltage potential is generated.
This ionize a gas (Xenon gas) to
produce a conductive gas(plasma)
The PAC light produces a high intensity
limited spectrum light that is filtered to
blue light in the range of 460 – 490 nm
Able to cure composites with photo-
initiators other than Camphorquinone.
Typically an exposure of 10 seconds
from a PAC light is equivalent to 40
seconds from a QTH light. Use of 2
mm increments is still required.
39. Advantages -
Shorter polymerization time (6-10 seconds)
Shorter curing times makes overall procedures shorter
and more integrated
Disadvantages –
increased heat production .
Expensive.
Most of the devices are large, heavy and bulky.
Rapid polymerization can increase the polymerizatin
shrinkage.
40. Argon laser emit a monochromatic coherent
light in wavelength (488nm) that cover the
blue light region of the visible light spectrum.
Does not employ filters.
Five seconds argon laser exposure results in
a resin composite cure at 2mm depth
laser curing light
41. Advantages
Increased degree of polymerization compared to standard
QTH units.
Greater depth of cure.
Polymerization is uniform even if light guide is at a distance
from the material.
Disadvantages
Adjacent restorations may be affected by lasers.
Rise in temperature may damage the pulp.
Rapid polymerization can increase polymerization shrinkage.
42. Solid state LEDs use junctions of doped semiconductors based
on gallium nitride to emit blue light.
Spectral output of blue LEDs falls between 450 and 490 nm,
which is in the absorbance range of camphoroquinone.
43. Generations of LED’S –
First generation - relatively low-powered chips offering a
comparative low output and poor curing performance
compared with conventional QTH lights
Second generation - have a single high-powered diode
with multiple emission areas E.g. Elipar Freelight 2
Third generation - they have two or more diode
frequencies and emit light in different ranges to activate
CQ and alternative photo-initiators. E.g. – UltraLume 5
Elipar Freelight 2 Jetlite 5000
44. Advantages -
Consistent output, with no bulbs to change
No need for filter systems
Low power consumption (battery-operation is possible)
Long service life of LEDs(10,000 hrs)
Quiet
Cordless, light weight
Disadvantages -
Due to the narrow emission spectrum LEDs can only
polymerize materials with an absorption maximum
between 430 and 480 nm (camphorquinone as
photoinitiator)
Slower than PAC
Batteries must be recharged
Cost more than halogen lamps
47. Developed during the 1970s
filler used - finely ground amorphous silica
and quartz.
The average particle size is 8 - 12µm,
Filler loading generally is 70 – 80 wt% or 60 –
70 vol%
Indication – used in class II and class IV
48. Clinical considerations
Produce rough surface
Restorations tend towards discolouration.
Poor resistance to occlusal wear
Can be used for stress bearing class 4 cavities.
Advantages Disadvantages
Compressive, tensile
strength
Stiffness
Hardness
Polymerization shrinkage
Water sorption, thermal
expansion
Polishability
Surface roughness
Staining, plaque
Occlusal wear
Poor esthetics
49. Introduced to overcome the disadvantages of traditional
composite
Inorganic fillers are ground to a size range of
approximately 0.5 to 3µm, but with a fairly broad size
range distribution
Contain more inorganic filler (80 wt% to 90 wt% and 65
to 77 vol%) than traditional composites
Use amorphous silica as filler, but most incorporate
glasses that contain heavy metals for radiopacity. Colloidal
silica added in amounts of approximately 5 wt% to adjust
the viscosity of paste.
Silane-coated
silica or glass
(1-5 u)
Polymer
matrix
50. Clinical application –
Indicated for application in which large stresses and
abrasion might be encountered
Attain a reasonably smooth surface for anterior application
but not as good as hybrid or microfilled composites.
Advantages Disadvantages
Good mechanical
properties
Good smoothness
Less polymerization
Shrinkage
Radiopacity
Prone to wear and
deterioration.
51. Introduced in late1970s
Individual particles are approximately 0.04 µm (40nm) in
size - Colloidal silica particles
Inorganic filler content - 35 to 60% by wt.
The greater surface area per unit volume of these
microfine particles, the microfill composites cannot be
heavily filled
Approaches to increase the filler loading
Sintering the colloidal silica
Organic filler –prepolymerized particles.
Final inorganic filler - 50 wt%; if composite particles
counted as filler particles, the filler content is closer to 80
wt% (approx 60 vol %)
Ground
polymer
with
colloidal
silica (50 u)
Polymer
matrix
with
colloidal
silica
52. Clinical consideration –
In stress-bearing situation, the potential for fracture is greater
Diamond burs rather than fluted tungsten-carbide burs are
recommended for trimming
Low modulus of elasticity – suitable for restoring class V
cervical lesions or defects where cervical flexure can be
significant
Smoothest surface finish among all composite resins.
Indications
Esthetic anterior restorations.
Restoring sub-gingival areas.
Carious lesion on smooth surface (Class 3 and 5)
53. Advantages Disadvantages
Best surface finish
Excellent wear resistance
Decreased tensile strength
Higher Water sorption and
CTE
fracture resistance is les
54. Developed to combine properties of conventional and
microfilled composites
Contain two kinds of filler particles - colloidal silica and
ground particles of glasses containing heavy metals
Content of approximately 75 to 80 wt%.
Average particle size of about 0.4 to 1.0 µm
Colloidal silica represents 10 – 20 wt% of total filler
content.
Silane-coated
silica or glass
Polymer
matrix with
colloidal
silica
55. Clinical considerations –
Surface smoothness and reasonably good strength – used in
anteriors including Class IV
Provides a smooth “Patina-like” surface texture in finished
restoration.
Currently are the predominant direct esthetic restorative
material used.
Have almost universal clinical applicability
Advantages Disadvantages
Good physical properties
Improve wear resistance
Superior surface
morphology
Good esthetics
Increased surface
roughness with time
58. PHYSICAL PROPERTIES
WORKING & SETTING TIME
Light cure: surface hardens in 60-90 sec
Chemical cure: 3-5 min
Polymerization shrinkage –
Microfill composite – 2 to 3%
Packable composite – 0.6 to 0.9%
Macrofilled composite – 1.2 to 1.3%
Small particle filled composite – 2 to 3%
Thermal properties –
The thermal conductivity of composites with fine particles (25 to 30 ×10-4
cal/sec/cm2[0C/cm]) is greater than that of composites with microfine
particles (12 to 15 ×10-4 cal/sec/cm2[0C/cm]).
59. Water sorption – (in mg/cm2)
Traditional composite – 0.5 to 0.7
Small particle composite – 0.5 to 0.6
Hybrid composite – 0.5 to 0.7
Microfilled composite – 1.4 to 1.7
Color stability:-
Stress cracks within the polymer matrix and partial
debonding of the filler to the resin as a result of hydrolysis-
increase opacity and alter the appearance.
Discolouration can also occur by oxidation.
Chemical cure less than light cure.
61. Wear –
Ability to resist surface loss
Wear resistance of
composite are of at least
five types –
Wear by food (CFA wear)
Impact by tooth contact in centric
contacts (occlusal contact area
wear) (two-body concept)
Sliding by tooth contact in function
(functional contact area wear)
Rubbing by tooth contact
interproximally (proximal contact
area wear)
Wear from oral prophylaxis
methods (toothbrush or dentifrice
abrasion)
62. Marginal integrity
exhibit good marginal adaptation when the
margins are on enamel and dentin.
Poor adaptation to root surfaces.
To enhance the marginal adaptation, reducing the
microleakage of composite restorations - 5 ways
(Cheung, J prosth Dent,1990)
Acid etch technique
Dentin bonding
Cavity design
Incremental technique
Sealing the margins-unfilled resin
63. Radiopacity
important requirement for composite resins.
imparted by certain glass filler particles containing heavy metal
atoms .
Even at highest volume fraction of filler, the amount of radiopacity
is less than amalgam.
64. Biocompatibility
Direct biological risk
Post-placement tooth sensitivity
Local immunological effects
Long-term pulpal inflammation.
estrogenic in in vitro studies.
May elicit allergic reactions, or may possibly
Even act as carcinogens
Indirect biological risk –
◦ Post-operative sensitivity, pulpitis, and secondary caries
resulting from microleakage/nanoleakage.
65. FLOWABLE COMPOSITES
Introduced in 1996
Resin matrix- TEGDMA( Triethylene glycodimethacrylate)
Fillers - silica(0.02- 0.05µm)
- 60% by weight
Indicated in low stress bearing areas where increased flow of
composite resins is desirable.
Clinical consideration:
Pit& fissure sealants
Preventive resin restorations
Small class III & v restorations
Liners in class I & II cavities(especially in proximal box)
Repair of ceramic crown bridge
66. Matrix consists of ceramic polysiloxane(silicon-
oxygen chains) instead of bis-GMA
Low shrinkage on polymerization(only 1.8%)
Versatile in application in both anterior and
posterior regions of the mouth.
Has high abrasion resistance.
Also releases fluoride, calcium & phosphate ions
67. Have nanofillers(Size: 0.005-0.01µm)
These particles are extremely small & virtually
invisible.
Incorporation of 90-95 % fillers by weight-high
filler levels result in good physical properties and
esthetics.
Commercially available: Filtek™ Supreme Plus
68. Chlorhexidine-
toxic effects of the released material
Antibacterial activity is short lived
Deterioration of the properties of the material
Imazato et al(1994)-
MDPB (methacryloxydecyl pyridinium bromide)=
hydroxydodecyl pyridinium bromide+ meth acryloyl group
- Antibacterial effect even after long term immersion in water
- Also no adverse effects on properties of resin matrix.
- Effective against streptococci
Silver
“Oligodynamic action” on bacteria's.
69. Calcium phosphate and its modified varieties are being
used as fillers in recent composites.
serve as bioactive liners and bases to enhance
remineralization.
When ph of saliva drops, ca and po4 ions are released.
Amorphous calcium phosphate hybridized with glass
forming agents are also used as filler.( Ariston pH control)
‘smart composite’
70. Developed in 1998.
Fibers of glass or polyethylene & resin matrix
being coupled during manufacture.
end result is fibres uniformly impregnated with the
matrix.
71. Properties
Very high compressive strength and tensile strength.
High flexural strength
Uses
Inlays, onlays, full veneer crowns.
Restoration of endodontically treated teeth.
Metal free composite crowns.
3-unit bridges.
Splinting .
72. Composites have provided clinicians with wide range
of restorative options. Since last two decades these
materials have risen exponentially and have enabled
the dentist to implement preventive & minimally
invasive techniques. Today, aesthetics and
restorative dentistry are unthinkable without
composite resins. The most important aspect , is
that patients retain their teeth longer with better
esthetics. Interest in the scientific background,
development and performance of these restorative
materials is a must to avoid being snared by
advertising promises.
Editor's Notes
Mps-most commonly used.
Light activated-initially uv light..today visible blue light activated systems.-greatly improved depth of cure, controllable working time.
Studies hav shown that greater amount of bacteria & plaque accumulates on the surface of the resins composites/ enamel surface. The more the plaque, greater is the incidence of secondary caries.
