Composites Flashcards
The success of a restoration depends on (2)
Operator and technique
What do we consider with the selection of restorative material? (3)
- Age: time it’ll be in the mouth
- Risk of caries: risk of filtration and secondary caries
- Child cooperation: moisture control
What is composite resin?
Polymeric material
What is the structure of composite resin? (5)
Methacrylate polymers –> monomer with doble
bond –> polymerization –> breaking of the doble bonds –> unión in long chains of polymers
Composite resin: obturation material adheres _____ to the tooth surface, not …. (2)
- micromechanically
- not depending on a specific design
Clinical success of composite resin depends on? (3)
- Process of adhesion
- Interphase sealing
- Avoids bacterial invasion
Define adhesion
State where 2 surfaces stay together through forces based
on chemical and/or mechanical mechanisms with the mediation of an adhesive.
Composite resin: 2 types of adhesive?
1-They need acid etching (conditioning of the surface with
orthophosphoric acid)
2-Self-etching adhesive
Composition of composite resin? (4)
- Organic matrix(resine).
- Inorganic matrix. Filler particles.
- Agent of Union (Silane)
- Photosensible molecules and starters of the polymerization
Composite resin organic matrix? (2)
• Matrix does not differ much between different
composites. Most use Bowen´s resin or the BisGMA (bisphenol A-glycidyl methacrylate).
• TEGMA added due to the great viscosity of the BisGMA.
Composite resin inorganic filler and fractures?
Gives physical resistance to fractures
Composite resin inorganic filler reduces…? (2)
- Contraction of polymerization
- Coefficient of thermal expansión
Composite resin inorganic filler usually made of? (5)
- Quartz
- Silica
- Boron
- Barium
How are composite resins classified? (3)
Size, shape and amount of the
filler
Composite resin classification depending on size of particle? (4)
- Macrofiller (no longer sold)
- Microfiller
- Nanofiller
- Hybrid
Composite resin classification depending on amount of filler? (3)
- Fluid composite
- Condensable composite
- Bulk composite
Size of macrofiller particles?
10-100 um
Size of microfiller particles?
0.1-1 um
Properties of hybrid particles in composite resin? (3)
- It contains macro and microfiller
- Bigger resistance than microfiller
- Better polishing than macrofiller
Size of nanofiller particles?
0.0005 - 0.01 um