1. Innovations in dental composites
Present by:Dr Tahere Sanei

2. Composite !!! What does it mean?
Materials made up of 2 /+ distinct, chemically different phases
The resulted material (composite) combine the properties of the phases included
Examples
Jell-o & fruits
Concrete
Tooth enamel and dentine
Resin composite

3. + Polymerization-associated additives Organic phase (matrix)
Dispersed phase
(fillers)
Matrix phase
Coupling phase
Polymerization-associated additives
Coloring additive
Ultraviolet stabilizers
Radioopacifiers
Organic phase (matrix)
Inorganic dispersed phase (fillers)
Coupling phase +

4. Organic Phase (Resin Matrix )
Monomer system
- BIS-GMA or UDMA. (viscous monomers)
- Silorane resins (in the most recent, minimal-shrink type)
2. Diluents
- TEGDMA & HEMA
Function
Hold all ingredients in one mass
Able to polymerize (Responsible for material’s setting )
Accept pigments (Responsible for material’s color )
Responsible for the setting contraction

5. Dispersed Phase (Fillers )
1. Inorganic fillers
- Quartz, glass, barium and lithium alumino-silicates, barium fluoride
- Zinc (Zn), Boron (B), zirconium (Zr) and yttrium (Y) ions are added to produce radioopacity
2. Pre-polymerized organic fillers
- Ground resin composites
3. Alternative fillers
- fibers, tri-modal, non-slumping fillers, fluoride-releasing – Nano-sized fillers
Function
 Mechanical Prop.
 Wear resistance
 Coeff. of th. Exp.
 Poly. shrinkage

6. Classification based on filler size and loading
Types
Filler size
Filler load
Traditional types
1. Macro-filled
8-12 µm
75-80 wt%
2. Small particle
1-8 µm
70-85 wt%
3. Hybrid
0.4-1 µm
70-75 wt%
4. Micro-filled µm
50-60 wt%
Recent types
5. Nano-hybrid
(Av 0.6) µm
6. Nano-filled
Culsters µm (5-20 nm)
Macro-filled
Small-particle
Hybrid
Micro-filled

7. Polymerization associated additives
Polymerization initiator…..
Benzoyl proxide in case of chemical and heat-cured materials
Camphroquinon in case of light-cured materials
Polymerization activator…Tertiary amine in case of chemically-cured materials
Polymerization inhibitor… (hydroquinon) prevents material’s polymerization on storage

8. Innovations in dental composites
1.monomer systems
2.Molecule-sized reinforcing filler phase
3.photocuring

9. monomer systems
A)polycarbonate dimethacrylate: cured polymer is a polyester using carbonate, packable like amalgam, photocurable in bulk system, readily curable without generation high residual shrinkage stress.
"Alert" is a polycarbonate dimethacrylate product (Pentron)

10. monomer systems
B)HMW urethane with a rigid central section and flexible end groups.
Provide rodlike shapes that facilitate self assembly into compact molecular structure, due to HMW: reduce curing shrinkage with the flexible end groups promote reactivity and enhance monomer-polymer conversion.
Kalore also known as DX-511(GC)

11. monomer systems
C)Dimethacrylate with a bulky, space filling central group
The bulky three-ring central groups hold the monomer apart and thus slow the rate of polymerization. This lengthens the time needed for the cross-linking reaction and relieves developing stresses, result in lower curing-stress resins.
Venus Diamond (Heraeus Kukzer)

12. monomer systems
D)HMW phase separating dicarbonate with hydrophobic side chains
This monomer is analogous to TDC-urethane dimethacrylate and having a HMW similar to that of DX-511, provide double bond dilution and hence reduce shrinkage and greater conversion.
A further advantage is the hydrophobic nature of the center group, which restrict water absorption and solubility with the other dimethacrylate in the formulation. Formation of two separate phases during polymerization led to a small expansion.
N̛ Durance (Septodont)

13. monomer systems E)Silorane
These tetra functional silorane monomers cured with low shrinkage via a cationic cross-linking mechanism by means of ring opening, result in expansion.
Filtek LS (3M)

14. The development of minimal-shrink composites was based on ….
1. Increasing the filler load
Using prepolymerized composite fillers
Using nano-sized fillers (Tetric Evoceram, Ivoclar-Vivadent)
2. Using organic matrices with lower polymerization shrinkage
Spiro-orthocarbonate, can produce composites with no setting contraction,
Oxy bis-methacrylates (bifunctional monomer) shows also a reduced rate of the polymerization contraction
Oxirane and silorane-based monomers (Feltick LS, 3M-ESPE)

15. Polymerization shrinkage of new minimal-shrink composites

16. reinforcing filler phase
2.Molecule-sized reinforcing filler phase
A)Originally modified ceramic oligomers (ormocer)
They are considered to be molecule-sized hybrid structures consisting inorganic-organic copolymers. These nanoparticles do not produce separate phase. High molecular weight, flexible, relatively low viscosity, crosslinkable molecules produce.

17. reinforcing filler phase
The large spacing between crosslinks resulting from curing produces a low level of polymerization shrinkage, while the inorganic network provides abrasion resistance through its hydrophpbicity.
Advantage: limited cure shrinkage, very high biocompatibility, good manipulation properties and excellent esthetic.
Definite , Admira (Voco) Ceram-X (Dentsply)

18. reinforcing filler phase

19. reinforcing filler phase
B)Polyhedral oligomeric silesquioxane (POSS)
POSS molecules and 12-sided silicate cages produce from silane and functionalized to composite polymerized with other monomers. POSS is a molecule sized hybrid organic-inorganic oligomeric compound that can disperse homogenously in compatible monomer and become covalently incorporated into cross-linked networks upon curing. Like the ormocer-type material, the silicate cage structure provide a reinforcing function, but filler particles must also be included to achieve the balance of mechanical and other properties required for adequate performance.

20. reinforcing filler phase
POSS-based resins are characterized as being highly polishable and having excellent polish retention, mechanical properties, and wear resistance.
Artiste Nano-Hybrid composite (Pentron)

21. Nano-filled Flowable Composites
Utilizes nano-sized fillers.
Still flows readily
Excellent aesthetics
Low wear
Available in capsules

22. Smart Composites

23. It is a kind of ion-releasing composites
It releases fluoride, hydroxyl and calcium ions, when the pH in areas adjacent to the restoration drops down (e.g. plaque accumulation)
Recent materials are based on alkaline glass fillers. The release of alkaline ions helps in;
1. Inhibiting bacterial growth
2. Buffering the acids produced by bacteria
3. Reduce the incidence of recurrent caries (Reduce the demineralization)

24. self adhesive composite

25. bulk fill dental composite

26. photocuring 3.photocuring training, evaluation, and process management
The MARC (acronym for: managing accurate resin curing) device and training system.
Measure both the irradiance and the energy received by the simulated preparations in a mannequin head

27. MARC

28. photocuring
The device can use to determine: spectral irradiance, total energy delivered over a given exposure duration, estimated exposure duration needed to deliver a specific energy dosage and ability of various lamps to deliver adequate energy level between different tooth location.

29. Compomers (Polyacid-modified composites)

30. To have a kind of modified composite having the main advantages of glass ionomer cement.
Compositional modifications
Certain liquid monomer (HEMA) is modified by polyacrylic acid grafts
Filler particles similar to the powder of glass ionomer cement (calcium- fluoro-alumino-silicate- glass)
Drawbacks:
Using bonding systems still mandatory
Lower wear resistant < regular composites
Insignificant release of fluoride

31. Flexure strength Taher NM
Flexure strength Taher NM. Comparative study of composite, compomer and ormocer bi-axial flexural strength. Saudi Dent. J. (2002) 14:7-10.

33. To overcome some drawbacks of compomers
The filler particles are a kind of pre-polymerized glass ionomer agglomerates
Giomers are fluoride releasing light-cured restoratives. They show a true hybridization of glass ionomers and composites as they have the fluoride release and recharge of glass ionomers and the aesthetics, handling and physical properties of composite resins.

34. Fiber-reinforced composites

37. THANK YOU