Resin Composites Flashcards
What are the four components of composites?
- Matrix made of ORGANIC polymers
- Fillers made of inorganic particles such as glass or cermaics
- Coupling agents: Inorganic compound that bonds matrix and filler
- Initiator-Accelerator Systems
Ceramic have very ______ while polymers have very ______.
This makes resin composites fall ________ in terms of mechanical strength.
very high mechanical properties
Very low mechanical properties
Resin composites fall right between ceramic and polymers
What are the two most common resins?
Both of these are ________ and _________liquids.
Dimethacrylate (Bis-GMA)
Urethane dimethacrylate (UDMA)
Oligomers and viscous liquids
How do we reduce viscosity of __________ and ____________ ?
Bis-GMA ,UDMA
Add low molecular weight dimethacrylates such as TEGDMA and Bis-EMA6
Why is it important to reduce viscosity of resin composites?
To facilitate manipulation
What is the advantage of acrylic resins?
Lower polymerization shrinkage
Fillers can make up _________ to _____ in weight of the composite.
They control the ________ such as _______ and are usually particles of _______.
30-70% in weight of the composite
properties of the composite such as mechanical, water sorption, shrinkage
Particles of Glass
What glass is used in fillers?
Ceramics such as quartz, lithium aluminum silicate
What controls the properties of the composite?
Fillers
Radiopaque fillers include
barium
strontium
zinc
borosilicates
aluminosilicates
Fillers can reduce _________.
Shrinkage
What are the three categories of filler size?
Fine : 0.2 ro 3 micrometers/microns
Microfine : 0.04 microns
Nanofine: 1-100 NANOmeters
________ which are about _________ in size can agglomerate and form a ________
Nanofine, 1-100 NANOmeters, nanocluster
______ nanometers = _______ micrometer/micron
1000 = 1
The size-distribution of fillers can be split into _______ and _______.
Hybrids: Different Sizes
Filled: Similar sizes
What are two other options of fillers?
- Fiber-reinforced
Glass Fibers or Polyethylene or Aramid
- Nano-tubes
Carbon
Halloysite
Ceramics, Carbides, Zinc Oxide ..
Fiber-reinforced fillers include ______, ______ and ________.
_________ are ______ cost and have good adhesion
______ have __________ and poor adhesion
glass fibers, polyethylene fibers and aramid fibers
Glass , low cost, good adhesion
Polyethylene Fibers , enhanced mechanical properties, poor adhesion
Macrofill
10-50 micrometer sized particles
Microfill
40-50 NANOmeter sized particles that agglomerate
Hybrid
Some Macrofill (10-50 microns)
Some Microfill (40-50 nm)
Midifill
1-10 microns
40 nanometer
Minifill
0.6-1 microns
40 nanometer
Nanofill
5-100 NANOmeters
We can classify composites by consistency
________ composites have better ________/______. It reduces _________ but also reduces __________.
_________ allows formation of ____________ and has modified ___________ or other types of ________.
Flowable, adaptation/dispensing
Filler content but also reduces mechanical properties
Packable , tight interproximal contacts
filler size distribution or other types of fillers
