composite resin

Question 1

in dental composite, resin matrix phase is reinforced by dispersed ___ particle phase bound to the resin by a ________ and an initiator-accelerator system

Answer 1

filler particle phase

bound to resin by a silane coupling agent

Question 2

bis-GMA (most widely used)
UDMA
TEGDMA

Answer 2

resin matrix

Question 3

what is silica

Answer 3

a filler particle dispersed in resin matrix and need this for composite

Question 4

-reinforcement of resin matrix
-decreased polymerization shrinkage
-decreased thermal expansion and contraction
-viscosity control
-decreased water sorption
-increased radiopacity

Answer 4

benefits of filler particles

Question 5

monomers to be converted into polymers

and process is triggered by

Answer 5

composites

by free radicals (heat, light)

Question 6

BHT andd hydroquinone

Answer 6

polymerization inhibitor

Question 7

metal oxides=

Answer 7

=pigments

Question 8

3 classifications of composities

Answer 8

1. filler particle size and size distribution
2. handling characteristics
3. type of polymerization

Question 9

what type of force breaks brittle materials (when they are weakest)

Answer 9

tensile strength (pulling)

Question 10

where do caries spread more rapidly

Answer 10

in the dentin

Question 11

tapered fissure bur

Answer 11

169

Question 12

BURS CREATE INTERNAL ROUNDED LINE ANGLES

(UNDERCUTS)

Answer 12

245 AND 330

undercuts anything that converges

Question 13

preserve marginal ridge and no undermined enamel (resistance)

Answer 13

divergence

Question 14

retention of isthmus

Answer 14

converging

Question 15

what carie fluoride protects again the most

Answer 15

smooth caries

Question 16

type of hybrid filler we use now

Answer 16

mini-nano hybrid

Question 17

packable composite:
flowable:

Answer 17

packable- medium viscosity
low viscosity

Question 18

advantage is bulk placement
disadvantage is mixing
no control of working time

activator and initiator?

Answer 18

chemical cure
act- aromatic tertiary amine
init- benzoyl peroxide (BPO)

Question 19

most common
adv- control of working time and no mixing
act and init?

Answer 19

light cure
act- blue ligiht
initiator- camphorquinone (468nm)

Question 20

tip size of curing light?

Answer 20

smaller tip increases output and heat

Question 21

oxygen inhibited layer is how many microns thick

Answer 21

15

Question 22

stress level will vary depending on the type of restoration configuration factor:

higher this, higher stress

Answer 22

c factor

Question 23

what will decrease c-factor

Answer 23

incremental placement. stress reduced not shrinkage

Question 24

lower filler size=

Answer 24

higher surface finish

Question 25

lower filler amount, higher water sorption=

Answer 25

higher expansion bisGMA higher sorption

Question 26

important to distinguish carious tissue and marginal adaptation, air bubbles (defects)

Answer 26

radopacity

Question 27

removes minerals from dental substrate allowing adhesive infiltration

Answer 27

acid etching

Question 28

phosphate monomer that chemically interacts via ionic bonding to calcium in hydroxyapatite

Answer 28

1-MDP (chemical bonding)