1) Dental composites are resin-based materials reinforced with filler particles that are used for tooth-colored restorations. They have evolved from large macrofilled particles to smaller microfilled and nanofilled particles for improved esthetics. 2) Modern composites come in various types depending on their handling properties, including packable, flowable, and bulk-fill versions. They are also classified based on their filler sizes as macrofilled, microfilled, or hybrid. 3) Resin composites offer esthetic, conservative restorations but have disadvantages like polymerization shrinkage, sensitivity to technique, and relatively lower wear resistance compared to other materials. Continual development aims to improve their mechanical properties and

1. COMPOSITE RESTORATIVE MATERIALS
Dr Shrimant Raman
DEPARTMENT OF PROSTHODONTICS

2. DEFINITION
• A 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 short fibers bonded to the matrix by a
coupling agent.
• A 3 dimensional combination of at least two chemically
different materials with a distinct interface separating
the components.

3. Time Line of Development of Composites

4. CLASSIFICATION
Accordingly to the particle size
Megafillers- contains very large filler particles.
Macrofillers- 10-100 µm
Midifillers - 1-10 µm
Minifillers- 0.1-1 µm
Microfillers- 0.01-0.1 µm
Nanofillers- 0.005-0.01 µm
Hybrid

6. Homogenous Composite
• It is a composite that simply consists of filler and uncured matrix
material. It contains only microfillers.
Heterogeneous Composite
• It is a composite that consists of microfillers and pre-cured matrix
material.
Based on handling characteristics / viscosity
• Packable Composites
• Flowable Composites
Based on polymerization method
• Self curing
• UV- light curing
• Visible light curing
• Dual curing

7. Based on applications and commercial availability
• Restorative composites: direct intraoral restorations
- Hybrids
- Microfilled
- Flowable
- Packable
- Nano composites
• Core build up composites
• Prosthodontic composites (veneers, crowna and FPD’s)
• Provisional composites (temporary crowns, restorations)
• Luting composites

8. INDICATIONS FOR COMPOSITES
1. For esthetically pleasing restorations.
2. As a provisional restoration in teeth with doubtful prognosis.
3. Ceramic crowns, posts, inlay, onlay and laminates
4. erosion and abrasions lesions
5. Provisional splinting.
6. Post & core
7. Midline diastema closure
8. Pit & fissure sealant

9. CONTRAINDICATIONS
1. Improper isolation of operating site.
2. All occlusal contacts will be on composite material
3. Heavy occlusal stresses
4. Deep sub-gingival areas that are difficult to prepare or restore.
5. Poor oral hygiene.

10. Advantages
• Show high esthetics
• Minimal tooth preparation
• Possess low thermal conductivity and shows bonding
with enamel and dentin
• Finishing and polishing can be done immediately after
curing the restorations
• No galvanism, as it doesn’t contain any metal

11. Disadvantages
• Polymerization shrinkage leads to gap formation on the
margin resulting in secondary caries and staining.
• More expensive
• Requires proper isolation and have multiple steps
• Technique sensitive in comparison to other materials
• Low-wear resistance

12. IDEAL REQUIREMENTS
• Should have CTE closer to that of enamel
• Should not absorb water
• Should have minimum or no polymerization shrinkage
• Should have good wear resistant
• Should have smooth surface texture
• Should be radiopaque
• Should have high modulus of elasticity
• Should be less soluble in oral fluids

13. Supplied as :
• Composite resin – either
chemical or light cured
• Etching liquid (37%
phosphoric acid)
• Bonding agent

14. COMPOSITION
Filler
Coupling
agent
Resin
matrix

15. In addition they contain :
• Activator-initiator system – to activate setting mechanism, chemical or
light curing chemicals
• Polymerization inhibitor (0.01%) – prevents premature polymerization,
thus, increasing working time for chemically activated resin. Eg.
Butylated hydroxytoluene (BHT) 0.01 wt%
• UV stabilizers/absorbers – to improve color stability, prevent discoloration.
Eg. 2-hydroxy-4 methoxybenzophenone
• Opacifiers – titanium oxide and aluminium oxide
• Color pigments – to match tooth color

16. 1) Resin Matrix
Used earlier – BIS-GMA (Bowen's resin)
(Bisphenol-A glycidyl dimethacrylate)
USED NOW A DAYS-
• UDMA (Urethane dimethacrylate)
• TEGDMA ( Triethylene Glycol dimethacrylate)
• HEMA (Hydroxy Ethyl methacrylate)
• EGDMA (ethylene glycol dimethacrylate)

17. 2) Fillers
Added to increase
-
Addition of fillers decreases
- Thermal Expansion & Contraction

18. Factors affecting role of filler :
a) Amount of filler added (b) Size of particles and its distribution
(c) Shape of fillers (d) Refractive index (e) Radiopacity (f) Hardness

19. Types of fillers:
• Quartz: extremely hard, difficult to grind in filler particles
• Silica : as pure, fused, colloidal
• Glasses or ceramic containing heavy metal
• Other such as tricalcium phosphate and zirconium
dioxide
• Fillers containing fluorides – Ytterbium trifluoride (YbF₃)

20. 3) Coupling agents
• Chemical bond between filler particle and resin matrix.
• If not incorporated or use then it leads to microscopic defects
• Microleakage of fluids into these defects led to surface
staining and failure.
• Organosilane (3-methacryl-oxypropyl-trimethoxysilane)
• Other are zirconates and titanates

21. Functions :
• Transfer of stresses
• Prevent water penetration into filler resin interface
• Bond fillers to the matrix thus reducing wear

22. Polymerization Mechanisms
• This process is carried out by initiators and activators
by addition polymerization process.
• Based on mode of activation of polymerization, there
are 3 main types :
- Chemically activated resins
- Light-activated resins
- Dual cure

23. Chemically activated composite resins :-
• Two paste system
- Base paste - benzoyl peroxide (initiator)
- catalyst paste – tertiary amine activator

24. Light activated composite resins :-
• Under normal light they don’t interact
• Photoinitiator(Camphorquinone) is activated under light
of wavelength 400-500nm
UV light activated system – used initially to activate free
radicals, but it have certain drawbacks

25. Visible light – activated systems –
• Improved depth of cure and a controlled working time
• Single paste system – camphorquinone 0.25 wt% and amine
accelerator DMAEMA(dimethylaminoethyl-
methacrylate)0.15wt%
Dual Cure Resins :- combination of above two curing systems

26. Curing lamps
• These are handheld devices, which are capable of
emitting light
• Consists of small & rigid light guide, which is made up of
fused optical fibers
• Filtered to transmit light only in visible range (400-500
nm) activate the photoinitiator, camphorquinone in
light cure resins, by releasing free radicals to begin the
polymerization

27. Factors influencing polymerization process:
- Wavelength
- Intensity
- Time of exposure
• Maximum curing – 16,000mJ/cm² is required to cure
2mm thick layer of resin
• Light emitting 400mW/cm² - 40 seconds
• Light emitting 800mW/cm² - 20 seconds

28. Types of lamps used for curing :-
1) LED lamps:
- light-emitting diodes
- 440-480nm,blue part of visible spectrum
- Don’t require filters
Benefits -
• Require low voltage,
• battery operated,
• don’t generate heat,
• don’t require cooling fan,
• long life span
Drawback – produce low intensity radiation

29. 2) QTH lamps :
• quartz-tungsten-halogen lamps
• Earliest and most common forms of
light cure systems
• Use quartz bulb with a tungsten
filament
• Light source emits white light, which
is filtered to remove heat and all
wavelengths except those in the
violet-blue range b/w 400-500nm

30. • Intensity of bulb reduces with use, so calibration meter is
required to measure the output intensity
• Power density : 300-1200 mW/cm² in the violet spectrum
Eye protection –
• protective eye device for direct visual during curing
procedure
• Direct and continuous observation of tip can cause retinal
damage to the eyes.

31. Factors influencing reduction of intensity of light
from QTH lamps:
• Light tip is chipped off
• Resin is deposited on the light tip
• Distance of the tip to resin is increased
• Lack of uniformity across the light tip
• Burn out of the bulb filament
• Change in line voltage

32. 3) PAC lamps :
• Plasma arc curing lamps
• Use xenon gas ionization to
produce plasma that forms
b/w two tungsten electrodes
under pressure
• High intensity white light
filtered to remove heat and
to allow blue light to be
emitted

33. • Light intensity light is obtained at the lower
wavelength
• Exposure from PAC light for 10 sec is equal to
40 sec exposure from QTH
• Therefore, save time in procedures

34. 4) Argon laser lamp :
• Highest intensity
• Emit at a single wavelength of 490nm
• Designed to emit light in only blue spectrum, which lies
in the photo absorption range of camphorquinone
• Therefore, don’t require filters

35. Macrofilled Composites
• Also known as traditional or conventional composites
• Large size of filler particle size
• Rarely used now a days
• Composition – ground quartz (8-12μm)
- as large as 50μm may also be present
• Filler loading 70-80 wt% or 60-70 vol%

36. Properties :
• All mechanical properties like strength, modulus,
hardness have improved in comparison to unfilled
restorative resin. Also water resorption is less than that
of unfilled resins
Drawbacks :
• Polishing results in rough surface compromised esthetics
• Poor resistance to wear
• Tendency to discolour – rough surface tends to stain

37. Microfilled Composites
• Also known as microfine composites
• Overcome the disadvantage of surface roughness
• Inferior mechanical properties than conventional due to
less filler content
• So used in stress free area for esthetic purpose and
where smooth finish is required for reduced plaque
accumulation

38. • Composition: colloidal silica (0.04 to 0.4 μm)
• 200-300 times smaller
• 70 wt% or 60 vol% (organic fillers)
• Inorganic actual filler is 50 wt%
Manufacturers tried to overcome it:
• Using pre polymerized or organic fillers, heterogeneous

39. Hybrid Composite
• Contain 2 types of filler particles – colloidal silica and ground
particles of glasses containing heavy metals.
• Filler content is approx 75-80 wt%. Or 60-65 vol%
• The glasses have an average particle size of about 0.4 to 1 µm.
• Multipurpose composite
• E.g Clearfill APX, Profill, and NV

40. Packable Composites
• Based on the newly introduced concept called PRIMM (polymer rigid
inorganic matrix material). This system consists of a resin and a ceramic
component.
• The fillers are incorporated as a continuous network/scaffold of
ceramic fibers.
• Include elongated, fibrous, filler particles of about 100 µm in length,
and/or textured surfaces that tend to interlock and resist flow causing
the uncured resin to be stiff and resistant to slumping, yet moldable.
• (i)Solitaire
(ii) Alert
(iii) Surefill
(iv) Filtek P60

41. Flowable Composites
• Low-viscosity resin composites for the first increment.
• Flow more readily than standard hybrid formulations and will therefore easily
and thoroughly adapt to all areas of the cavity preparation.
• Lower filler content (30-55 vol%) than hybrid and reduced elastic modulus
• High polymerization shrinkage and low wear resistance than micro hybrid
composites
• FloRestore
• Flow-it
• Tetric Flow (Vivadent)

42. Manipulation of Composite Resins

43. THANK YOU