Resin Composites 1

Question 1

what make up the resin matrix?

Answer 1

methacrylate or dimethacrylate monomers

Question 2

what are examples of monomers

Answer 2

BISGMA

Urethane dimethacrylate

Question 3

What are examples of co monomers?

Answer 3

TEGMA

Question 4

What does TEGMA do?

Answer 4

controls viscosity

Question 5

What else are present in resin composites?

Answer 5

inhibators

Question 6

What do products based on silorane produce?

Answer 6

expansion that offsets shrinkage

Question 7

what do c=c bonds take part in?

Answer 7

free radical polymerisation

Question 8

What do unreacted monomers in resin composites allow for?

Answer 8

scope for chairside repair

Question 9

What does the viscosity of the matrix polymer do?

Answer 9

reduces mobility of untreated monomers

Question 10

What are two types of siloranes?

Answer 10

siloxanes

oxiranes

Question 11

what do siloxanes contribute to resin composties?

Answer 11

factor of hydrophobicity

Question 12

What do oxiranes contribute to resin composites?

Answer 12

ring opening polymerisation

Question 13

catatonic cure?

Answer 13

camphorquinone
iodium salt
electron doner
ring opening polymerisation
allows for less shrinkage

Question 14

what are fillers?

Answer 14

quartz
silica
glasses

Question 15

What are glasses in resin composites?

Answer 15

aluminasilicates
bora silicate
barium oxide

Question 16

what are coupling agents?

Answer 16

methacryloxypropyltrimethoxysilane

silane interacts and bonds with glass

Question 17

What does high filler content mean?

Answer 17

higher surface hardness

Question 18

what does high filler content mean re. volume setting contraction?

Answer 18

higher filler the lower % of volume setting contraction

Question 19

The higher filler means what to thermal expansion?

Answer 19

higher filler, the less co efficient of thermal expansion

Question 20

what does camphorquinone do re. polymerisation

Answer 20

yields necessary free radical to start polymerisation

Question 21

at what level does camphorquinone become excited?

Answer 21

40-60 nm- visable blue light

Question 22

What is blue light most readily generated by?

Answer 22

quartz halogen lights

Question 23

What is the downside to resin in composite?

Answer 23

susceptible to shrinkage upon polymerisation

Question 24

what are resins?

Answer 24

modified methacrylate/acrylate

oxirane- ring opening

Question 25

what is the function of the filler>

Answer 25

shock absorber

Question 26

What is the function of the coupling agent?

Answer 26

transfers stress from loading from rigid riller to more flexible and ductile matrix

Question 27

What are the types of resin composites?

Answer 27

conventional- used for posterior/ occlusal restoration micro filled- anterior hybrid nano composites

Question 28

What other properties are there to resin composite?

Answer 28

gradual set from outer surface | required incremental cure

Question 29

with increased porosity?

Answer 29

less strength | less fatigue

Question 30

with decreased coupling?

Answer 30

less strength | less fatigue

Question 31

What is cfactor?

Answer 31

measure of bond strength | number of bonded surface/number of unbonded surfaces