Phillips Dental Materials Restorative Resins

Question 1

What are 3 structral components of dental Resin-Based Composites?

Answer 1

1 Matrix
2 Filler
3 Coupling Agent

Question 2

What is the most widel used monomers of dental composites?

Answer 2

bis-GMA

Question 3

What is the primary purpose of the filler material in dental composites?

Answer 3

To strengthen a composite and to reduce the amount of matrix material
To help prevent or reduce shrinkage

Question 4

What are commonly used filler particles?

Answer 4

quartz
glasses
silica

Question 5

As partical size decreases what happens to total filler surface area?

Answer 5

Increases

Question 6

What is a typical inhibitor found in resin systems and what are two general functions of inhibitors?

Answer 6

Butylated hydroxytoluene (BHT)
Extend storage lifetime
Ensure sufficient working time

Question 7

As shades of composite darker what are two things dentists must do to ensure correct curing?

Answer 7

Increase curing time
Thinner layers (less than the typical 2-3 mm)

Question 8

LED lamps emit what kind of light and in what spectrum?

Answer 8

Blue spectrum between 440-480 nm (this isn’t actually completely true any more)
Do not require filters and do not generate heat

Question 9

QTH lamps emit what kind of light and in what spectrum?

Answer 9

Violet-Blue range 400-500 nm

Filtered light that heat

Question 10

What are dual-cure resins?

Answer 10

Chemical and light curing resin

Question 11

What are characteristics of Traditional Composites?

Answer 11

Rough surface that develops after abrasive wear
Tend to discolour
Poor resistance to occusal wear
Comparatively larger filler particles

Question 12

What are characteristics of Small-Particle-Filled Composites (SPF)?

Answer 12

More inorganic filler compared to Traditional
Good for high stress and abrasion prone applications like Class IV sites
Smoother than Traditional but less smoth than microfilled composites

Question 13

What are characteristics of Microfilled Composites?

Answer 13

Tiny silica particles that tend to agglomerate (looks like rouleaux in cats rbcs!)
Increased viscosity
Less inorganic filler compared to SPF or Traditional and therefore less shrinkage
Wear faster, best for Class III and Class V
Best for aesthetic restorations

Question 14

What are characteristics of Hybrid Composites?

Answer 14

Two kinds of filler: silica and heavy metal with glass
Best for anterior restorations Class IV
Very similar mechanical properties to SPF

Question 15

What are characteristics of Flowable Composites?

Answer 15

Less filler which decreases viscosity
More susceptible to wear
Class 1 restorations