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RECENT ADVANCES IN
COMPOSITES
By sathwik
CONTENTS
• Introduction
• Briefly on composites
• Research on advances in composites
• Direct composites
• Packable
• Flow...
Smart composites
Siloranes
Glass inserts
Anti bacterial composites
Chitosan composites
Bio active composites
Flouride rele...
• Indirect composites
• Art glass
• Bell glass HP
• sinfony
• Ceromer
• Fiber-reinforced substructure
• Other important ad...
INTRODUCTION
• This highly competitive market continues to evolve, with the major emphasis in the past being to produce
ma...
DEFINITION
According to Anusavice
• It may be defined as a compound of two or more distinctly different materials with pro...
HISTORY
• 1955: Buonocore – acid etch technique
• 1956: Dr.Bowen formulated Bis GMA
• 1962: Silane coupling agents
• 1970:...
HISTORY
• Early 1980’s : hybrid composite
• Mid 1980’s: First generation indirect composites
• Early 1990’s: Second genera...
COMPOSITE RESINS
3 structural components – matrix, fillers & coupling agent
Matrix - BIS-GMA, TEGDMA, UDMA
TEGDMA- Diluent...
• Coupling agent :
• Organosilanes (-methacryloxypropyltrimethoxy silane) It contains Silanol group and methacrylate grou...
•shrinkage
•flouride
•Bio compatability
•polishability
•strength
Why
POLYMERIZATION INDUCED SHRINKAGE
• Failure in composite restoration
• Several generalized approaches have been attempted
•...
ADVANCES IN CURING PROTOCOL
1. photoinitiation
In this visible-light-activated initiator system, camphorquinone (CQ) absor...
• naturally occurring 1,3-benzodioxole and its derivatives were evaluated as potential replacements for
conventional amine...
2.ALTERNATIVES TO CAMPHORQUINONE/AMINE SYSTEMS
• Phosphine oxide initiators
• benzoylgermanium derivatives have been synth...
3.SOFT-START CURING
• The soft-start curing method originated with work by (Unterbrink and Muessner, 1994, 1995) (Braga et...
ADVANCES IN MONOMER FORMULATIONS
• The resin phase is composed primarily of dimethacrylate monomers typically selected fro...
1.MULTI METHACRYLATES
• Bile acids were utilized as starting materials to form multimethacrylate monomers (Gauthier et al....
2.ULTRARAPID MONOMETHACRYLATES
• Inclusion of monovinyl monomers into dental resins was changed with the development by De...
3.ACIDIC MONOMERS
• Incorporating acidic monomers in relatively small mole fractions into methacrylate resins may enable a...
NOVEL POLYMERIZATION MECHANISMS
1.POLYMERIZATION-INDUCED PHASE SEPARATION
• In one creative approach, specific methacrylat...
2.THIOL-ENE PHOTOPOLYMERIZATION
• The thiol-ene polymerization reaction proceed via a step-growth polymerization mechanism...
3.HYBRID POLYMERIZATION REACTIONS
• Hybrid polymers are formed from co-monomers with different reactive groups that polyme...
4.RING-OPENING POLYMERIZATION
• unique shrinkage behavior observed in these polymerizations.
• ring-opening reaction relie...
FILLER AND FILLER MODIFICATION
• A study on the influence of mono-,bi-, and tri-modal distributions of fillers on the wear...
SILANE TREATMENT OF INORGANIC FILLERS
• Surface modification of most fillers used in dental composites is necessary:
• (a)...
Packable
• Introduced as amalgam alternatives.
• Supplied:
• Unit-dose, compules or in syringes.
• Higher filler loading:
...
• Non sticky
• Easily transferable and packable.
• Moisture tolerant
• High critical shear bond strength
• Has excellent v...
Polymeric rigid inorganic
matrix material
• Inorganic phase:
• Continuous network or scaffold of ceramic fibers-
Alumina a...
Advantages :
Produce acceptable class II restorations.
• High depth of cure possible.
Reduced polymerization shrinkage.
As...
Disadvantages
• 1. Less polishable.
• 2. Limited shades.
• 3. Increased post- op sensitivity.
• 4.  Sensitivity to ambien...
PRODUCT MANUFACTURER
Solitaire Heraeus Kulzer
ALERT Jeneric-Pentron
SureFil Dentspl y/Ca u I k
Prodigy Condensable KerdSyb...
Solitaire
67% filler volume
Releases fluoride.
34
• 70% filler volume.
• Very good for
proximal Contacts.
80% filler vol E...
BulkFill composites
Reduced polymerization
shrinkage-Changes in
filler composition-
shrinkage stress relievers
or polymeri...
Flowable composites
• Introduced in late 1996
• Similar to resin cements &pit and fissure sealants with filler loading + ...
Advantages
 Low viscosity
 Easy to use
 Improved marginal adaptation
 High wettability
 High depth of cure
 Penetrat...
Artiste® nano-hybrid Flowable composite
40
Exceptional polish ability
Reduce shrinkage
Increase wear resistance
ENA HRi flow
No bubbles formulation
• HRi features breakthrough technology - a light refractive index (1.62) that is
ident...
• An aesthetic gingiva-shaded light-cured composite resin recently
introduced, providing practitioners with the option of ...
Cervical area,
including composite
restorations in
gingival colours
V-shaped defects
Exposed cervical
areas
Aesthetic
corr...
Esthet x flow
• Pseudo plastic handling - flows on command
• Superb strength and wear resistance
• Highly radiopaque
• Low...
• Low stress applications but not in class I and II in premolars and molars.
• Resurfacing composite or GIC restorations o...
• Contains the major ingredients of both composites (resin component) and glass
Ionomer cements (Polyalkenoate acid and gl...
Strength and Wear Performance:
GIC – 140 MPa,
composite- 300 MPa,
compomer 200 – 250 Mpa
• Dyract has 3 times the wear rat...
Indications
Indications
Sealing
occlusal pits
and fissures
Restorations
of primary
teeth
Minimal
cavity
preparations
Linin...
Advantages:
• Superior working characteristics to RMGIC
• Ease of use
• Easily adapts to the tooth
• Good esthetics
EX: DY...
• GIOMER is basically a modified GLASS IONOMER.
• It is a true hybrid of two compounds, Glass
Ionomer and Composite
• The ...
COMPOSITION of GIOMER :
• Bisphenol A glycidyl
dimethacrylate&TEGDMA
• Inorganic glass filler-Aluminuoxide, silica
• Pre-r...
• Reactmer bond is the glass ionomer based, tricurable, all -in-one, filled
adhesive based on PRG technology
52
Indications:
Restoration of Class I.
II. III. IV, & V
Restoration of cervical
erosion and root caries
Laminate veneers and...
Limitations:
• Giomers are not as beneficial as GIC’s in
patients who are at risk for recurrent
caries
• Long term fluorid...
• Dr. Herbert Wolters from Fraunhofer Institute for Silicate Research introduced
this class of material in 1994
• acronym ...
• Smart Composites are active dental polymers that
contain bioactive amorphous calcium phosphate (ACP)
filler capable of r...
Based on a newly developed alkaline glass filler and is expected
to reduce the formation of secondary caries at the margin...
• Smart composites work is based on the newly developed alkaline glass. The paste
contains Ba, Al, and F silicate glass fi...
Smart nano composites
• In 2007,Hockin Xu used nanosized(25-100nm)Dicalcium phosphate with reinforcing
nanofillers – Load ...
Siloranes
• Guggenburger and Weinmann (2000)
• Siloxane + oxiranes
• Siloxane backbone – hydrophobic nature
• Ring opening...
As silorane-based composite
polymerizes, “ring-opening”
monomers connect by opening,
flattening and extending toward
each ...
Filtek™ P90 low shrink posterior restorative
system
• Combines the lowest-shrinking
silorane-based composite with a
dedica...
Glass inserts
• An alternative to conventional composites has been developed (Bowen et al, 1991)
known as "Megafilled" com...
65
Available insert systems:
Beta quartz: glass ceramic inserts:
• Beta quartz inserts are manufactured of a cast glass ceram...
Ceramic leucite reinforced Ceramic inserts:
• Cerafil inserts consists of a dental ceramic reinforced by leucite crystals....
Antibacterial composites
• Chlorhexidine has been tried in an attempt to reduce plaque accumulation on the
surface of fill...
Imazato et al (1994) attempted to make the composite antibacterial by
incorporating a non releasing newly synthesized mono...
• Silver has also been added in the composites to make it antibacterial - ‘oligodynamic
action’
• Silver can be added eith...
Antibacterial activity of dental composites containing zinc
oxide nanoparticles.
June 2010 in J Biomed Mater Res B appl bi...
Chitosan composites
• Chitosan and chitosan derivatives appear to be good candidates for the
elastomeric matrix. These nat...
• Bioactive formulations:
• -ACP (amorphous calcium phosphate)-2000
• -ACP + BIS-GMA /TEGDMA/HEMA with Zirconyl methacryla...
Amorphous calcium phosphate (ACP)
• Replace missing/decayed tooth structure by remineralization-Antonucci , Skrtic
• Inter...
Hydroxyapatite (HAP)
• As a reinforcing filler
• Synthetic HAP- hardness similar to tooth- Improved wear
• Intrinsic radio...
Flouride releasing composites
• Tanaka et al used methacryloyl fluoride – methyl methacrylate copolymer in
pit and fissure...
• Compobonds exploit the benefits of SE DBAs and nanofilled resins, eliminating the
precursory bonding stage necessary to ...
Trade name :- vertise flow
First compo bond introduced in
2009 by (Kerr Corp., USA)
Self adhering flowable combining
a res...
Preoperative view showing the existing
amalgam restorations which were in need
of replacement.
Amalgam restorations were r...
The completed self-etching, self-
bonding flowable composite
restorations.
Application of the flowable composite
into the ...
Fusio™ liquid dentin
• It is a 4-META (4-methacryloxyethyl trimellitic acid) based flowable composite
featuring nano-sized...
Characteristics and properties of compo bonds
•Acts as a Shock Absorber beneath resin-based composite
restorations.
Incorp...
• Because Compobonds function both as a dentine adhesive and a
resin restorative material, a Longer Curing Time Is Necessa...
• Nanotechnology consists of reducing components of a material to the nanometric
scale for use in a new material to improv...
Nanoparticles
• Particles of size  1-100 nm in diameter exhibit unique electronic, optical,
photonic and catalytic proper...
Advantages of nano fillers
Does not thicken the
resin
Size (0.4-0.8µ).
Enhance the
polishability of resin.
An extreme surf...
• Nano hybrid composites have nanometer sized
particles combined with more conventional filler
technology.
• Nanofilled re...
Nanomer
Discrete non-agglomerated and
non-aggregated particles of 20-75
nm
Nanotubes
Nanotubes have remarkable
tensile str...
TRADE NAMES TYPE OF NANO COMPOSITES IMPORTANT POINTS
Tetric EvoFlow NANO-OPTIMIZED FLOWABLE Class V restorations , fissure...
TRADE NAMES TYPE OF NANO COMPOSITES IMPORTANT POINTS
Ceram·X™ duo+ Nanohybrid
Double Translucency System
•highly esthetic ...
TRADE NAMES TYPE OF NANO COMPOSITES IMPORTANT POINTS
Filtek™ Z350 Universal
Restorative
NANOHYBRID •Low polymerization shr...
TRIMODAL APPROACH TO NANOTECHNOLOGY
Premise Universal
Indirect composite resins
• Three type of composite materials are available for use in indirect
technique,microfilled resi...
 Early 1980s, Mormann and Touati Composite resins for the fabrication of indirect
inlays and onlays
 Mid 1980Touati an...
• Launched in 1995 by Heraeus-kulzer
COMPOSITION
Silica-reduces slumping, improve sculptability, high degree of conversion...
Bell glass HP
Bell de in 1996
The opaceous dentin material of BelleGlass HP
incorporates a specific filler size and partic...
Sinfony
• Introduced by 3M ESPE
Matrix Filler
Polyfunctional
metharylate
polymer
Pyrogenic silica
0.05µ Visco alpha
haloge...
Ceromers:
• The term ceromer stands for Ceramic Optimized Polymer and was introduced by
Ivoclar.
• Composed of specially d...
Ceromers combine the advantages of ceramics and composites
• Durable esthetics
• High abrasion resistance
• High stability...
• Ivoclar in 1996
• Provided –base, dentin and
incisal shades
Targis
101
Matrix Filler
BisGMA Ceromer (ceramic –
optimized...
Laboratory based, Preimpregnated fiber reinforced
systems
Targis/vectris:
• Highly filled Targis Ceromer (ceramic optimize...
Sculpture/fibrekor:
• Involves veneering a composite resin (Sculpture) to a resin
preimpregnated glass fiber network (Fibr...
Single crystal modified composites
• Have symmetric shapes like long plates and behave like fibers.
• An experimental indi...
105
fiber reinforced composites
Properties of FRC:
• Geometrical arrangement of fibers
Wave, Braided, Unidirectional, Mesh...
106
Forms
• Short staple:
Reduces matrix volume
Improves wear resistance
• Long lengths:
Can improve strength and stiffnes...
107
Classification
• Pre- Impregnated Lab Products ( ex: vectris)
• Pre- Impregnated chairside products ( connect – kerr)
...
Advantages
• Single visit immediate treatment
• Suitable for transitional& long term replacement.
• Suitable for young pt
...
Disadvantages:
• Potential wear of overlying veneering composite—pt with para
functional habits
• Excellent moisture contr...
Clinical applications
• Reinforced resin based composites.
• Individual restorations (inlay, onlay, full veneer crown).
• ...
GC EVEREX posterior:
The short fibres used in everX
Posterior provide a fracture
toughness equal to collagen-
containing d...
113
• They are available as:
• Light cure
• Dual cure
• Self cure
Core build up composites
• Ti-Core EDS
• Core paste Den-...
114
Composite splints
• Resins along with the reinforcement of
fibers can also be used as splints for
esthetic purposes.
•...
115
Root posts
• Resin reinforced with carbon or quartz fibers have been
used to produce black or white root posts with st...
Future advances
• Carbon Nanotubes- Applications of carbon nanotubes
reinforcement of composites
• Boron nitride Nanotubes...
Liquid crystals
• Liquid crystals are structurally
intermediate between liquids and solids
• Transforming from a highly or...
Quantum dot materials
• Quantum dots are a unique
class of semiconductor
particles, ranging from 2-10
nanometers (10-50 at...
Quantum dot composites
• Quantum dots exhibit high fluorescent brightness, stable, long
lasting, and have narrow emissions
Self-repairing Composites:
• One of the first self-repairing synthetic materials reported,
interestingly shows some simila...
Conclusion
• The field of composite dental restoratives continues to propose and
achieve significant and exciting advances...
• Properties of packable dental composites. J Esthet Dent. 2000;12(4):216-26.
• Dental Ceramics and Ormocer Technology - N...
• Dental materials(2005),21,68-74
• Dental materials(2002).18,413-421
• Journal of esthetic dentistry (2000)12,216-226
• J...
recent advances in composites
recent advances in composites
recent advances in composites
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recent advances in composites
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recent advances in composites

  1. 1. RECENT ADVANCES IN COMPOSITES By sathwik
  2. 2. CONTENTS • Introduction • Briefly on composites • Research on advances in composites • Direct composites • Packable • Flow able • Compomers • Giomers • Ormocers
  3. 3. Smart composites Siloranes Glass inserts Anti bacterial composites Chitosan composites Bio active composites Flouride releasing composites Compo bonds Nano-composites
  4. 4. • Indirect composites • Art glass • Bell glass HP • sinfony • Ceromer • Fiber-reinforced substructure • Other important advances • Future advances
  5. 5. INTRODUCTION • This highly competitive market continues to evolve, with the major emphasis in the past being to produce materials with adequate strength, and high wear resistance and polishability, retention. • The more recent research and development efforts have addressed the issue of polymerization shrinkage and its accompanying stress, which may have a deleterious effect on the composite/tooth interfacial bond. • Current efforts are focused on the delivery of materials with potentially therapeutic benefits and self- adhesive properties, the latter leading to truly simplified placement in the mouth.
  6. 6. DEFINITION According to Anusavice • It may be defined as a compound of two or more distinctly different materials with properties that are superior or intermediate to those of the individual constituents
  7. 7. HISTORY • 1955: Buonocore – acid etch technique • 1956: Dr.Bowen formulated Bis GMA • 1962: Silane coupling agents • 1970: First photo cured composites using UV light • 1972: Visible light curing unit was introduced • 1976: Micro filled composites
  8. 8. HISTORY • Early 1980’s : hybrid composite • Mid 1980’s: First generation indirect composites • Early 1990’s: Second generation indirect composites • 1996: Flowable composites & Ceromer indirect composites was introduced • 1997: Packable composites • 1998: Ormocers was developed • 2003: Nano filled composites resins • 2009: self adhesive composites
  9. 9. COMPOSITE RESINS 3 structural components – matrix, fillers & coupling agent Matrix - BIS-GMA, TEGDMA, UDMA TEGDMA- Diluent monomer , cross- linking Fillers - ↑ comp strength, tensile strength, stiffness, abrasion resistance, hardness ↓ wear, poly shrinkage, thermal exp & contr, water sorption Quartz or glasses, amorphous silica {0.1 – 100 µm},30- 70 vol % or 50 –85% wt Refractive index: BIS-GMA – 1.5, TEGDMA – 1.46, Quartz – 1.55
  10. 10. • Coupling agent : • Organosilanes (-methacryloxypropyltrimethoxy silane) It contains Silanol group and methacrylate group Activator – initiator system: • Chemically activated resins- Benzoyl peroxide + Tertiary amine • Visible light activated resins – camphoroquinone(0.2wt%) +DMAEMA(0.15 wt%)(N ,N -dimethylaminoethyl methacrylate) Inhibitor – Butylated hydroxytoluene(0.01 wt%) Optical modifiers – TiO 2, Al 2O3 (0.001 – 0.007 wt %)
  11. 11. •shrinkage •flouride •Bio compatability •polishability •strength Why
  12. 12. POLYMERIZATION INDUCED SHRINKAGE • Failure in composite restoration • Several generalized approaches have been attempted • (i) manipulating the curing protocol and timing to allow for relaxation and flow of the network prior to gelation • (ii) altering the amount of shrinkage that occurs through changes in the monomer or functional group density • (iii) changing the polymerization mechanism from conventional radical chain-growth polymerization of methacrylates to alter the network structural evolution.
  13. 13. ADVANCES IN CURING PROTOCOL 1. photoinitiation In this visible-light-activated initiator system, camphorquinone (CQ) absorbs a photon to generate a short- lived excited-state species that complexes with the tertiary amine to promote a sequential electron and proton transfer that creates the active α-aminoalkyl-initiating radical. ethyl-4-dimethylaminobenzoate (EDMAB), including N,N-dimethylaminobenzyl alcohol, 4- (N,Ndimethylamino)phenethyl alcohol (DMPOH), and N,N-3,5-tetramethylaniline (TMA) (Schroeder et al., 2007a, b,2008; Schroeder and Vallo, 2007)
  14. 14. • naturally occurring 1,3-benzodioxole and its derivatives were evaluated as potential replacements for conventional amine co-initiators and were found to be effective co-initiators, resulting in kinetics and polymer properties similar to those of equivalent systems initiated by CQ/EDMAB (Liu et al., 2007; Shi and Nie, 2007; Shi et al., 2007).
  15. 15. 2.ALTERNATIVES TO CAMPHORQUINONE/AMINE SYSTEMS • Phosphine oxide initiators • benzoylgermanium derivatives have been synthesized and demonstrated to be efficient visible light photoinitiators. • Some commercial formulations have included other photoinitiators, such as PPD (1-phenyl-1,2-propanedione), Lucirin TPO (monoacylphosphine oxide), and Irgacure 819 (bisacylphosphine oxide), which are less yellow than CQ and thus potentially more color stable. • Additional photoinitiators, such as OPPI (p-octyloxyphenyl-phenyl iodonium hexafluoroantimonate) have been proposed based on encouraging experimental results. • (Guo et al., 2008 • (Ganster et al., 2008a,b; Moszner et al., 2008b, 2009) • (Ogunyinka et al., 2007; Schroeder et al., 2007a, b, 2008; Felipe et al., 2008; Schneider et al., 2009
  16. 16. 3.SOFT-START CURING • The soft-start curing method originated with work by (Unterbrink and Muessner, 1994, 1995) (Braga et al., 2005; Ferracane, 2005) • Reduced irradiation intensity during the early stages of polymerization is hypothesized to allow stress relaxation to occur prior to vitrification • Extensive research has gone into and will continue to be devoted toward evaluating curing conditions and the subsequent effects on conversion, mechanical properties, and shrinkage stress.
  17. 17. ADVANCES IN MONOMER FORMULATIONS • The resin phase is composed primarily of dimethacrylate monomers typically selected from BisGMA, BisEMA, and/or UDMA. • monomers such as these generally result in low methacrylate conversion, which leads to significant amounts of unreacted monomer that may be leached from the restoration over time, resulting in concerns regarding long-term biocompatibility.
  18. 18. 1.MULTI METHACRYLATES • Bile acids were utilized as starting materials to form multimethacrylate monomers (Gauthier et al., 2009) • Polyhedral oligomeric silsesquioxane methacrylates (POSS-MA) were evaluated as alternatives to BisGMA (Fong et al., 2005), and it was found that small amounts of POSS-MA (2-10 wt%) did indeed improve the mechanical properties of these resins • Methacrylated beta-cyclodextrin derivatives have also been evaluated as alternatives to BisGMA and were found to exhibit flexural strength and volume shrinkage comparable with those of BisGMA/TEGDMA (Hussain et al., 2005).
  19. 19. 2.ULTRARAPID MONOMETHACRYLATES • Inclusion of monovinyl monomers into dental resins was changed with the development by Decker of a novel class of monovinyl (meth)acrylate monomers that exhibited greatly enhanced polymerization kinetics and significantly improved mechanical properties. • These materials showed great promise when utilized as diluents, and several monomethacrylates were evaluated as alternatives to TEGDMA (Lu et al., 2005; Kilambi et al., 2009)
  20. 20. 3.ACIDIC MONOMERS • Incorporating acidic monomers in relatively small mole fractions into methacrylate resins may enable a separate adhesive layer to be eliminated and result in improved overall performance. • Current acidic resins do not exhibit the necessary mechanical properties to function as resin-based composites, and hence research has focused on developing acidic monomers with improved mechanical properties. • (López-Suevos and Dickens, 2008).
  21. 21. NOVEL POLYMERIZATION MECHANISMS 1.POLYMERIZATION-INDUCED PHASE SEPARATION • In one creative approach, specific methacrylate monomers, chosen to be miscible as liquids but phase- separated at higher conversions, were incorporated into conventional methacrylate resins and composites. • When phase separation occurs, the volume expands, eliminating a portion of the volume shrinkage that arises from the methacrylate polymerization. • In particular, the use of dimer-acid-derived dimethacrylate (DADMA) monomers in novel dental resin formulations is examined as a potential means to address the combined aims of high conversion and low shrinkage and shrinkage stress.
  22. 22. 2.THIOL-ENE PHOTOPOLYMERIZATION • The thiol-ene polymerization reaction proceed via a step-growth polymerization mechanism in which propagation and chain transfer alternate (Cramer and Bowman, 2001; Hoyle et al., 2004, 2010; Lu et al., 2005; Hoyle and Bowman, 2010). • The step-growth nature of the polymerization results in uniform polymer networks with narrow glass transition regions and reduced brittleness. • Also, the gelpoint conversion is significantly higher in thiol-ene networks as compared with methacrylate networks. and • hence thiol-ene systems exhibit significant reductions in polymerization shrinkage stress (Carioscia et al., 2005; Lu et al., 2005; Cramer et al., 2010).
  23. 23. 3.HYBRID POLYMERIZATION REACTIONS • Hybrid polymers are formed from co-monomers with different reactive groups that polymerize via different curing mechanisms and are often utilized to synergistically achieve desired properties. • The order of the reactions can be controlled by the selective addition of inhibitors of each polymerization type or through manipulation of the initiating wavelength-initiator combination.
  24. 24. 4.RING-OPENING POLYMERIZATION • unique shrinkage behavior observed in these polymerizations. • ring-opening reaction relies on the opening of a cyclic structure to facilitate intermonomer bonding and crosslinking. • A recent exciting development in ring-opening polymerization is the commercial release of the cationically photopolymerizable silorane material (Filtek LS) by 3M/ESPE (Weinmann et al., 2005).
  25. 25. FILLER AND FILLER MODIFICATION • A study on the influence of mono-,bi-, and tri-modal distributions of fillers on the wear properties of composites showed that filler size and shape significantly influence wear resistance, with the inclusion of nano-sized filler a critical feature, often leading to enhanced properties (Turssi et al., 2005). • A method was developed to prepare single-walled carbon nanotubes (SWCNT) with suitable compatibility and polymerizability such that they could be introduced into dental composites as a secondary filler. • A good dispersion of the SWCNT in the composite was demonstrated, along with a significant increase in flexural strength compared with that of the unaltered composite material (Zhang et al., 2008).
  26. 26. SILANE TREATMENT OF INORGANIC FILLERS • Surface modification of most fillers used in dental composites is necessary: • (a) to reduce the filler surface energy such that composite paste consistency and hydrophilicity are reduced while filler dispersion within the resin is enhanced; and • (b) to provide a functional interface that permits covalent attachment between the polymer matrix and the reinforcing higher-modulus filler. • methacryloxypropyltrimethoxysilane (MPS) remains the most widely used surface treatment for the inorganic fillers used in dental composites
  27. 27. Packable • Introduced as amalgam alternatives. • Supplied: • Unit-dose, compules or in syringes. • Higher filler loading: • Fibers • Porous filler particles • Irregular filler particles • Viscosity modifiers.
  28. 28. • Non sticky • Easily transferable and packable. • Moisture tolerant • High critical shear bond strength • Has excellent visible light depth of cure • Cures rapidly to final hardness but with minimal residual stress • Little shrinkage on curing • Easily carved, burnished (smoothened).
  29. 29. Polymeric rigid inorganic matrix material • Inorganic phase: • Continuous network or scaffold of ceramic fibers- Alumina and silica dioxide fibers. • Fiber diameter is 2.0 um or smaller. • Cross-sectional dimension of scaffolding 150-200 um. • Silanation is completed with addition of BIS-GMA OR UDMA resin.
  30. 30. Advantages : Produce acceptable class II restorations. • High depth of cure possible. Reduced polymerization shrinkage. As low as 2%. • Filler loading: > 80% by weight. • Medium to high strength. • High stiffness. • Low wear rate: 3.5 um per year. • Modulus of elasticity: similar to amalgam 31
  31. 31. Disadvantages • 1. Less polishable. • 2. Limited shades. • 3. Increased post- op sensitivity. • 4.  Sensitivity to ambient light. 32 Recommended uses: • 1. Class I restorations. • 2. Class II restorations (2-3 surfaces).
  32. 32. PRODUCT MANUFACTURER Solitaire Heraeus Kulzer ALERT Jeneric-Pentron SureFil Dentspl y/Ca u I k Prodigy Condensable KerdSybron Filtek P60 3M Dental Products Pyramid Bisco, Inc. Glacier Southern Dental Industries Synergy Compact Coltene-Whaledent Definite Degussa
  33. 33. Solitaire 67% filler volume Releases fluoride. 34 • 70% filler volume. • Very good for proximal Contacts. 80% filler vol Easy to finish and polish Insensitive to ambient light
  34. 34. BulkFill composites Reduced polymerization shrinkage-Changes in filler composition- shrinkage stress relievers or polymerization modulators Increased depth of cure-Novel photo initiators,polymerizati on boosters or by increasing translucency Ease of flow& adaptability Higher strength & Better wear resistance Good esthetic properties
  35. 35. Flowable composites • Introduced in late 1996 • Similar to resin cements &pit and fissure sealants with filler loading + particles size less than hybrid composites resulting in a material of low viscosity. • Filler content less than 50% by vol polymerization shrinkage will be greater than for more heavily filled materials. 38
  36. 36. Advantages  Low viscosity  Easy to use  Improved marginal adaptation  High wettability  High depth of cure  Penetration  High flexibility 39 Disadvantages  wear  poor mechanical properties More polymerization shrinkage Sticks to the instrument
  37. 37. Artiste® nano-hybrid Flowable composite 40 Exceptional polish ability Reduce shrinkage Increase wear resistance
  38. 38. ENA HRi flow No bubbles formulation • HRi features breakthrough technology - a light refractive index (1.62) that is identical to natural enamel, with optical properties that can't be found in any other composite. • The ENA HRi Flow formulation eliminates air bubbles, resulting in superior physical properties. 41
  39. 39. • An aesthetic gingiva-shaded light-cured composite resin recently introduced, providing practitioners with the option of correcting gingival recession with a minimally invasive and less costly procedure. • Pink-colored composite  available in one translucent gingival color and 3 pink flowable opaquers  mixed together to better match an individual's gingival shade Gingival masking composites
  40. 40. Cervical area, including composite restorations in gingival colours V-shaped defects Exposed cervical areas Aesthetic corrections of the gingival area, Primary splinting, and the correction of red/white aesthetics Ability to mask exposed crown margins to improve aesthetics and patient satisfaction.
  41. 41. Esthet x flow • Pseudo plastic handling - flows on command • Superb strength and wear resistance • Highly radiopaque • Low shrinkage & porosity • 8 VITA shades plus 1 opaque and 1 bleach shade • Excellent polish & Fluoride release 44
  42. 42. • Low stress applications but not in class I and II in premolars and molars. • Resurfacing composite or GIC restorations or for rebuilding worn composite contact areas. • Areas of difficult access or areas that require greater penetration, amalgam, composite or crown margin repairs, pit and fissure sealant or preventive resin restoration. • As liner or base in class II proximal box. • Cementing porcelain veneers. • Restoration of air abrasion preparation, class v lesions, porcelain repairs, enamel defects, incisal edge repair in anteriors, class III lesions. Uses 45
  43. 43. • Contains the major ingredients of both composites (resin component) and glass Ionomer cements (Polyalkenoate acid and glass fillers component) except for water • Resin component  bulky macro-monomers, such (bisGMA) or UDMA with viscosity-reducing diluents, such as Triethylene glycol dimethacrylate (TEGDMA). • Fillers  fluoride containing glasses Compomers 46
  44. 44. Strength and Wear Performance: GIC – 140 MPa, composite- 300 MPa, compomer 200 – 250 Mpa • Dyract has 3 times the wear rate of a hybrid composite. 47 Fluoride Release : Dyract shows fluoride release for more that 12 months and maintains the same rate of diffusion. It is shown that more fluoride is released in acidic solution
  45. 45. Indications Indications Sealing occlusal pits and fissures Restorations of primary teeth Minimal cavity preparations Lining and Core build- up Repair of defective margins in restorations Class III, Class V, Erosion lesion - Restorations Sealing of root surface Potential root canal sealers Retrograde filing materials
  46. 46. Advantages: • Superior working characteristics to RMGIC • Ease of use • Easily adapts to the tooth • Good esthetics EX: DYRACT Ap, Compo glass F, Compo glass flow, F2000, Hytac
  47. 47. • GIOMER is basically a modified GLASS IONOMER. • It is a true hybrid of two compounds, Glass Ionomer and Composite • The properties of GIOMER is fluoride release and fluoride recharging of glass ionomer and esthetics, easy of polishing, and strength of composite. Giomers 50
  48. 48. COMPOSITION of GIOMER : • Bisphenol A glycidyl dimethacrylate&TEGDMA • Inorganic glass filler-Aluminuoxide, silica • Pre-reacted glass ionomer filler • DL-Camphorquinone 51
  49. 49. • Reactmer bond is the glass ionomer based, tricurable, all -in-one, filled adhesive based on PRG technology 52
  50. 50. Indications: Restoration of Class I. II. III. IV, & V Restoration of cervical erosion and root caries Laminate veneers and core build-up Ideal for pedodontic restorations Other dental applications  repair of fractured porcelain and composite restoration
  51. 51. Limitations: • Giomers are not as beneficial as GIC’s in patients who are at risk for recurrent caries • Long term fluoride release is questionable • Auj Yap etal (2002) hardness value (VHN) for Giomer was less than composite 54 Advantages: • Fluoride release • Biocompatibility • Clinical Stability and Durability • Excellent aesthetics • Smooth Surface Finish • Excellent Bonding
  52. 52. • Dr. Herbert Wolters from Fraunhofer Institute for Silicate Research introduced this class of material in 1994 • acronym of Organically Modified Ceramic • described as 3-dimensionally cross-linked copolymers. Composition: Ormocer 56 Silicon oxide, a filler--basic substance It is modified originally by adding polymerisable side chains in the form of methacrylate group Filler 1-1.5 µm in size material contains 77% filler by weight and 61 % by vol essential difference between ORMOCER and the previously available composites is found in the matrix The matrix, consisting of ceramic polysiloxane (siliconoxygen-chains) Ormocer was formulated in an attempt to overcome the problems created by the polymerization shrinkage of conventional composites because the coefficient of thermal expansion is very similar to natural tooth structure.
  53. 53. • Smart Composites are active dental polymers that contain bioactive amorphous calcium phosphate (ACP) filler capable of responding to environmental pH changes by releasing calcium and phosphate ions and thus become adaptable to the surroundings. • These are also called as Intelligent composite Smart composites 57
  54. 54. Based on a newly developed alkaline glass filler and is expected to reduce the formation of secondary caries at the margins of the restorations due to inhibition of bacterial growth, reduced demineralization and buffering of acids produced by cariogenic micro-organisms
  55. 55. • Smart composites work is based on the newly developed alkaline glass. The paste contains Ba, Al, and F silicate glass filler (1m) with Ytterbium trifluoride, silicon dioxide and alkaline glass (1.6 m) in dimethacrylate monomers • Ivoclar 1998 named Ariston pHC (pH control) which was claimed to release:Fluoride • Hydroxyl Calciumif PH falls in the vicinity of the restoration < 5.8 • This was said to neutralize acid and counter act the decalcification of enamel and dentine. 59
  56. 56. Smart nano composites • In 2007,Hockin Xu used nanosized(25-100nm)Dicalcium phosphate with reinforcing nanofillers – Load bearing, decay inhibiting ability • Nanofillers-Small fibres fused at high temp with Nanoscale silica particles • This material can buffer tooth against decay caused by acid producing bacteria by “Smartly” increasing ion release in presence of acids
  57. 57. Siloranes • Guggenburger and Weinmann (2000) • Siloxane + oxiranes • Siloxane backbone – hydrophobic nature • Ring opening monomers, cationic cure
  58. 58. As silorane-based composite polymerizes, “ring-opening” monomers connect by opening, flattening and extending toward each other. As methacrylate-based composites cure, the molecules of these “linear monomers” connect by actually SHIFTING closer together in a linear response.
  59. 59. Filtek™ P90 low shrink posterior restorative system • Combines the lowest-shrinking silorane-based composite with a dedicated two-step, self-etching bonding system.
  60. 60. Glass inserts • An alternative to conventional composites has been developed (Bowen et al, 1991) known as "Megafilled" composite restorations are produced by filling the bulk of the cavity preparation with beta-quartz glass inserts. • The inserts are surrounded by lightcured composite, which bonds to the insert via a silane coupling agent. The inserts are produced in a variety of shapes and sizes to fit most cavity preps. • When fitted into the cavity, they minimize the volume of shrinking composite and reduce curing contraction (George and Richards, 1993). The integration of inserts reduces the polymerization shrinkage stress and lowers the overall coefficient of thermal expansion. 64
  61. 61. 65
  62. 62. Available insert systems: Beta quartz: glass ceramic inserts: • Beta quartz inserts are manufactured of a cast glass ceramic based upon a lithium aluminium silicate with the addition of iron, sulphur. The surface of inserts is presilanized. Beta quartz silane liquid is available for the chairside resilanization of contaminated inserts 66 SDS feldspathic inserts: • SDS inserts ( Schumacher Dental Systems, Germany) consists of a feldspathic ceramic with a flexural strength of upto 10-20% greater Other insert systems
  63. 63. Ceramic leucite reinforced Ceramic inserts: • Cerafil inserts consists of a dental ceramic reinforced by leucite crystals. The cerafil system offers conical, symmetrical ceramic inserts of various sizes with matching preparation instruments and finishing diamonds. Sonic Sys leucite-reinforced ceramic inserts: • Sonic Sys inserts (Vivadent) are made of leucite reinforced glass ceramic. The Sonic sys inserts allows the finishing preparation and restoration of a non symmetrical proximal cavity. Cerena glass ceramic inserts: • Cerena inserts (Noediska Dental, Sweden) are manufactured of a translucent glass ceramic material without any addition of color pigments. 67
  64. 64. Antibacterial composites • Chlorhexidine has been tried in an attempt to reduce plaque accumulation on the surface of filling materials. However, this was not successful since the release was not uniform and lead to certain disadvantages like: • -toxic effects of the released materials • -population shift of microorganisms • - short-lived antibacterial activity • -deterioration of physical and mechanical properties of the materials. 68
  65. 65. Imazato et al (1994) attempted to make the composite antibacterial by incorporating a non releasing newly synthesized monomer, MDPB with antibacterial properties into the composite resin. Metacryloyloxydodicylpyridinum bromide MDPB was found to be effective against important species in plaque formation like actinomyces, Neisseria and veilonella 69
  66. 66. • Silver has also been added in the composites to make it antibacterial - ‘oligodynamic action’ • Silver can be added either: • Silver ions are incorporated into inorganic oxides like silicon dioxide • silver ions may be hydrothermally supported into the space between the crystal lattice network of filler particles. • Silver ions may be incorporated into the silica gel and the thin films are coated over the surface of composites. 70 1wt%halo(active against S.mutans and A. viscous for 10 wks).
  67. 67. Antibacterial activity of dental composites containing zinc oxide nanoparticles. June 2010 in J Biomed Mater Res B appl biomater, 94(1): 22-31. • It is demonstrated here that zinc oxide nanoparticles (ZnO-NPs) blended at 10% (w/w) fraction into dental composites display antimicrobial activity and reduce growth of bacterial biofilms by roughly 80% for a single-species model dental biofilm. • ZnO-NP-containing composites (10%) qualitatively showed less biofilm after 1- day-anaerobic growth of a three-species initial colonizer biofilm after being compared with unmodified composites, but did not significantly reduce growth after 3 days.
  68. 68. Chitosan composites • Chitosan and chitosan derivatives appear to be good candidates for the elastomeric matrix. These natural biopolymers are biocompatible ,biodegradable and osteoconductive. They have been used in surgical interventions for the reduction of periodontal pockets. • Biocompatibility , biodegradable, muco adherent • CPC–chitosan composites are stable in a wet environment and had sufficient physical strength for many clinical applications. The strength did not decrease with time under simulated physiological conditions. 72
  69. 69. • Bioactive formulations: • -ACP (amorphous calcium phosphate)-2000 • -ACP + BIS-GMA /TEGDMA/HEMA with Zirconyl methacrylate • Fluorinated Bis-GMA analogues • Liquid crystalline monomers Bioactive composites
  70. 70. Amorphous calcium phosphate (ACP) • Replace missing/decayed tooth structure by remineralization-Antonucci , Skrtic • Intermediate in hydroxyapatite formation • Single solid phase precursor • Biocompatible with hard & soft tissues • Sustain Ca & PO4 release • Effective remineralising agent – sealants, adhesives, bases, liners
  71. 71. Hydroxyapatite (HAP) • As a reinforcing filler • Synthetic HAP- hardness similar to tooth- Improved wear • Intrinsic radio opacity • Enhanced polish ability • Less expensive • Biocompatible • High refractive index
  72. 72. Flouride releasing composites • Tanaka et al used methacryloyl fluoride – methyl methacrylate copolymer in pit and fissure sealant where fluoride delivery lasted for 2 years (MF-MMA). • Kwan et al used Lewis acid i.e. BF3 and Lewis base i.e. diethylaminoethyl methacrylate into dental resin system fluoride is released by hydrolysis at a rate of 2-5µg/cm2/day for 1 year. • Other experiments are still under progress using – morpholinoethyl methacrylate hydrofluoride – tetrabutyl ammonium tetrafluoroborate.
  73. 73. • Compobonds exploit the benefits of SE DBAs and nanofilled resins, eliminating the precursory bonding stage necessary to adhere a resin to tooth substrate, and are termed Self-adhering Composites. COMPOBONDS
  74. 74. Trade name :- vertise flow First compo bond introduced in 2009 by (Kerr Corp., USA) Self adhering flowable combining a resin-based composite and a SE bonding agent based on the 7th generation DBA, OptiBond®All- in-One It is a light-cured composite with similar properties to conventional flowables but with the added advantage of eliminating the bonding stage. Self-etching/self-bonding restorative composites
  75. 75. Preoperative view showing the existing amalgam restorations which were in need of replacement. Amalgam restorations were removed Vertise (Kerr) flowable composite was dispensed onto a microbrush in order to accurately place it into the conservative preparation The cleaned-out preparations. A 37% phosphoric acid etchant (Kerr) was used on the cavo-surface margin.
  76. 76. The completed self-etching, self- bonding flowable composite restorations. Application of the flowable composite into the preparation. The restorative material was scrubbed onto the prepared tooth and then light- cured for 20 seconds.
  77. 77. Fusio™ liquid dentin • It is a 4-META (4-methacryloxyethyl trimellitic acid) based flowable composite featuring nano-sized amorphous silica and glass fillers. 81
  78. 78. Characteristics and properties of compo bonds •Acts as a Shock Absorber beneath resin-based composite restorations. Incorporates the properties of the 7th generation DBA, OptiBond® •1) Chemical adhesion by the phosphate function group of the GPDM& 4-META monomer uniting with the calcium ions within the tooth •2) Micromechanical adhesion by formation of the hybrid layer composed of resin impregnation with the collagen fibres and the dentine smear layer. The bonding mechanism to dentine is two-fold.
  79. 79. • Because Compobonds function both as a dentine adhesive and a resin restorative material, a Longer Curing Time Is Necessary to ensure that both constituents are fully polymerised. Light curing reaction also halts the etching process of the SE agent Increasing its pH from approximately 2 to 7 So that continual acidity does not erode the dentine bond.
  80. 80. • Nanotechnology consists of reducing components of a material to the nanometric scale for use in a new material to improve the final characteristics. • To estabilish polish of a microfill but the strength and wear resistance of hybrid composites (Swift, J Esth Rest Dent, 2005). Nanofilled composites
  81. 81. Nanoparticles • Particles of size  1-100 nm in diameter exhibit unique electronic, optical, photonic and catalytic properties. • Display properties intermediate between quantum and bulk material because of their intermediate size and large surface area-to-volume ratios. • Nanoparticles of different sizes and shapes exhibit different absorbance and fluorescence features
  82. 82. Advantages of nano fillers Does not thicken the resin Size (0.4-0.8µ). Enhance the polishability of resin. An extreme surface to volume ratio gives a high filler loading in a workable consistency. Increased wear resistance & hardness. 50% decrease in polymerisation shrinkage Reduced staining
  83. 83. • Nano hybrid composites have nanometer sized particles combined with more conventional filler technology. • Nanofilled resins have approximately 60% volume filler loading, making the Nanofilled resins as strong as the hybrid and micro hybrid resins. • Nanofillers have a refractive index of 1.508.
  84. 84. Nanomer Discrete non-agglomerated and non-aggregated particles of 20-75 nm Nanotubes Nanotubes have remarkable tensile strength Nanocluster Loosely bound agglomerates of nano-sized particles
  85. 85. TRADE NAMES TYPE OF NANO COMPOSITES IMPORTANT POINTS Tetric EvoFlow NANO-OPTIMIZED FLOWABLE Class V restorations , fissure sealing & adhesive cementation technique Filtek supreme XT NANOFILL COMPOSITES •Superior translucency and esthetics •Superior hardness, flexural strength and modulus of elasticity. •50% reduction in polymerization shrinkage. •Excellent handling properties.
  86. 86. TRADE NAMES TYPE OF NANO COMPOSITES IMPORTANT POINTS Ceram·X™ duo+ Nanohybrid Double Translucency System •highly esthetic restorations •Nano-Ceramic matrix in combination with the optimized filler particle size Ceram.X® mono+ Nano hybrid improved handling features; reduced stickiness and improved slump resistance. AELITE™ AESTHETIC ENAMEL Nano hybrid High strength Excellent polishability Easy manipulation and highly sculptable Low attrition and wear High flexural strength
  87. 87. TRADE NAMES TYPE OF NANO COMPOSITES IMPORTANT POINTS Filtek™ Z350 Universal Restorative NANOHYBRID •Low polymerization shrinkage. •High wear resistance •Anterior and posterior restorations, core- build-ups, splinting and indirect restorations Tetric EvoCeram (Ivoclar Vivadent) NANOHYBRID 3 types of nanoparticles - fillers, pigments and modifier. Anterior and posterior restorations. Aelite Aesthetic Enamel Bisco NANOHYBRID Filler 70 - 75% High strength,excellent polish ability Anterior and posterior restorations.
  88. 88. TRIMODAL APPROACH TO NANOTECHNOLOGY Premise Universal
  89. 89. Indirect composite resins • Three type of composite materials are available for use in indirect technique,microfilled resins (sr adoro ), small particle resins and hybrid resins. • New category of processed composite resin recently was introduced-polymer glass, polymer ceramic and Ceromer • All show excellent wear resistance & small particle composite resins and hybrid resins can be etched to produce micromechanical retention • They can all be silanated to increase bond strength 94
  90. 90.  Early 1980s, Mormann and Touati Composite resins for the fabrication of indirect inlays and onlays  Mid 1980Touati and Pissis developed the concept of metal composite inlays and bridges after the silanating technique  Disadvantages of direct composites:  Inadequate wear resistance  High incidence of secondary caries  Indirect composites:  Allow improved adaptation of the restoration to the cavity walls – better marginal integrity, less post operative sensitivity  Post-cure heat treatment (125° C or 275° F) increases double bond conversion- better polymerization, better wear resistance 95
  91. 91. • Launched in 1995 by Heraeus-kulzer COMPOSITION Silica-reduces slumping, improve sculptability, high degree of conversion (multifunctional monomers) xenon stroboscopic light ( high cross linking) Art glass 96 Matrix Filler Organic resin matrix Barium silicate glass 0.7µ
  92. 92. Bell glass HP Bell de in 1996 The opaceous dentin material of BelleGlass HP incorporates a specific filler size and particle distribution that helps to achieve thermal expansion, flexibility and stress response characteristics similar to natural dentin. • polymerized under pressure at elevated temperature 138ºc rate 20 min & in presence of Nitrogen , an inert gas. inc. polymerization &wear resistance.  Curing method- Light, heat and pressure  Improved D.C  Improved translucency 97 Matrix Filler Base : BisGMA Surface: TEGDMA Base : silanated microhybrid filler 0.6µ Surface: borosilicate
  93. 93. Sinfony • Introduced by 3M ESPE Matrix Filler Polyfunctional metharylate polymer Pyrogenic silica 0.05µ Visco alpha halogen lamp source 10sec Visco beta Fluorecent lamp source 15min
  94. 94. Ceromers: • The term ceromer stands for Ceramic Optimized Polymer and was introduced by Ivoclar. • Composed of specially developed & conditioned fine particle ceramic fillers - barium glass (< 1 µm), spheroidal mixed oxide, ytterbium trifluoride, and silicon dioxide (57 vol%) of submicron size ( 0.04 & 1.0 μm ), which are closely packed ( 75 – 85 weight %) & embedded in an advanced temperable organic polymer matrix-dimethacrylate monomers (Bis-GMA and urethane dimethacrylate. • Setting is by a polymerization of C=C of the methacrylate. 99 Advances in indirect composite resin systems
  95. 95. Ceromers combine the advantages of ceramics and composites • Durable esthetics • High abrasion resistance • High stability • Ease of final adjustment • Excellent polish ability • Effective bond with luting composite • Low degree of brittleness • Conservation of tooth structure
  96. 96. • Ivoclar in 1996 • Provided –base, dentin and incisal shades Targis 101 Matrix Filler BisGMA Ceromer (ceramic – optimized polymer) TARGIS gel TARGIS power curing unit Light emmision 10 min+ temp. 95ºC Cooling 5min
  97. 97. Laboratory based, Preimpregnated fiber reinforced systems Targis/vectris: • Highly filled Targis Ceromer (ceramic optimized polymer) composition, along with Vectris, a fiber reinforcing composite framework Consist of 2 major components 1. Targis - forms the bulk of the restoration 2. Vectris - fiber framework.
  98. 98. Sculpture/fibrekor: • Involves veneering a composite resin (Sculpture) to a resin preimpregnated glass fiber network (Fibrekor) • Fibers available in 15 cm lengths of various widths. • Sculpture is polycarbonate based composite resin. Ribbond: • It is a cross-linked leno stitch weave of polyethylene fibers. • Can be used chair side or in laboratory to fabricate composite resin bridges .
  99. 99. Single crystal modified composites • Have symmetric shapes like long plates and behave like fibers. • An experimental indirect composite system has been recently developed which uses silicon carbide single crystals as filler component. • These are silanized and incorporated into the resin matrix. 104
  100. 100. 105 fiber reinforced composites Properties of FRC: • Geometrical arrangement of fibers Wave, Braided, Unidirectional, Mesh • Nature of the fiber Stresses on the matrix are transmitted to fibers • Adequate adhesion of the fibers to the polymer matrix-Covalent bond Proper adhesion maximizes reinforcement and transfer of stresses Silane coupling agents – to improve adhesion
  101. 101. 106 Forms • Short staple: Reduces matrix volume Improves wear resistance • Long lengths: Can improve strength and stiffness • Woven material: Also improves strength and stiffness Assist in forming structure
  102. 102. 107 Classification • Pre- Impregnated Lab Products ( ex: vectris) • Pre- Impregnated chairside products ( connect – kerr) • Impregnation required- Chairside ( glaspan) • Preimpregnated prefabricated posts ( everstick )
  103. 103. Advantages • Single visit immediate treatment • Suitable for transitional& long term replacement. • Suitable for young pt • Metal free restoration • Improved esthetics • Easy to make • Can be frequently used with minimal or no tooth preparation • Less wear of opposing tooth as compared to traditional composites • Suitable for transitional and long term provisional restorations. • Readily repaired.
  104. 104. Disadvantages: • Potential wear of overlying veneering composite—pt with para functional habits • Excellent moisture control required– for adhesive technique • Space requirement greater in comparison to metal occlusal surfaces to allow sufficient room for fibers & adequate bulk for veneering composite onlay • May lack sufficient rigidity for long span bridges. • Uncertain longevity in comparison to traditional technique.
  105. 105. Clinical applications • Reinforced resin based composites. • Individual restorations (inlay, onlay, full veneer crown). • Periodontal splinting/ post trauma splint. • Immediate replacement trasitional-long term provisional bridges. • Fixed bridges-ant & posterior, 1. Simple cantilever 2. Implant supported • Reinforcing or repairing dentures. • Fixed orthodontic retainers.
  106. 106. GC EVEREX posterior: The short fibres used in everX Posterior provide a fracture toughness equal to collagen- containing dentine and almost double that of a conventional composite. composite restoration in large preparations.*
  107. 107. 113 • They are available as: • Light cure • Dual cure • Self cure Core build up composites • Ti-Core EDS • Core paste Den-Mat • Build-it J/P • Bis-core BISCO • Corestore Kerr • Fluorocore Caulk • Clearfil photocure J-Morita
  108. 108. 114 Composite splints • Resins along with the reinforcement of fibers can also be used as splints for esthetic purposes. • These fibers are strong and durable. • These are applied with flowable or hybrid composites. • They are available in different: • Thickness. • Breadth. • Pattern. System s Ribbond Ribbond Connect Kerr Splint-it J/P Glass span Glass Span
  109. 109. 115 Root posts • Resin reinforced with carbon or quartz fibers have been used to produce black or white root posts with stiffness similar to that of dentin. • Fiberglass resin posts – refracts and transmits light to the luting resin cements even after light curing cycle.
  110. 110. Future advances • Carbon Nanotubes- Applications of carbon nanotubes reinforcement of composites • Boron nitride Nanotubes Addition of small amounts of the carbon nanotube filler to a commercial composite (Durafill) yielded a material with good dispersion of the SWCNT, along with a significant increase in flexural strength compared with that of the unaltered composite material (Zhang et al., 2008).
  111. 111. Liquid crystals • Liquid crystals are structurally intermediate between liquids and solids • Transforming from a highly organized state at room or mouth temperature to an isotropic amorphous state when photocured, with sufficient expansion to offset the contraction that accompanies the formation of covalent bonds. • Used as Fillers as well as matrix in composites.
  112. 112. Quantum dot materials • Quantum dots are a unique class of semiconductor particles, ranging from 2-10 nanometers (10-50 atoms) in diameter. • The core-shell quantum dots have unique shells that stabilize the material, improve quantum yield and reduce photo-degradation.
  113. 113. Quantum dot composites • Quantum dots exhibit high fluorescent brightness, stable, long lasting, and have narrow emissions
  114. 114. Self-repairing Composites: • One of the first self-repairing synthetic materials reported, interestingly shows some similarities to resin-based dental materials , since it is resin based. • This was an epoxy system which contained resin filled microcapsules. If a crack occurs in the epoxy composite material, some of the microcapsules are destroyed near the crack and release the resin. • The resin subsequently fills the crack and reacts with a Grubbs catalyst dispersed in the epoxy composite , resulting in a polymerization of the resin and repair of the crack.
  115. 115. Conclusion • The field of composite dental restoratives continues to propose and achieve significant and exciting advances in resin formulation, filler loading and modification, and curing methodologies and mechanisms. • While most of the advances remain in the research stage, the future both in regards to research and in clinical practice remains bright with exciting new developments translated into practice at an ever- increasing rate 121
  116. 116. • Properties of packable dental composites. J Esthet Dent. 2000;12(4):216-26. • Dental Ceramics and Ormocer Technology - Navigating the Future!-A.Sivakumar • Polyacid-modified composite resins (“compomers”) and their use in clinical dentistry-John W. Nicholson∗ • Text book of operative dentistry:Summit • Text book of operative dentistry:Sturdvent • Esthetic Dentistry:Ascheim Dale:Second edition • Text book of operative dentistry-vimal .k .sikri • Jada-1997 • J am dent asso 132(5); 639-645,2001 122 References
  117. 117. • Dental materials(2005),21,68-74 • Dental materials(2002).18,413-421 • Journal of esthetic dentistry (2000)12,216-226 • J Am dent asso(1990),20;177 • Dental Materials Volume 20, Issuse 9, Pages 789-795, November 2004 • Journal of Esthetic and Restorative Dentistry Vol 11 issuse 5,pages 234–249, September 1999 • Dental Materials 19 (2003) 449–457 • Fiber-reinforced composites in clinical dentristry: Quintessence Books; 2000. • JDR:91- 1178-1783-December 2012 123

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