Compoaite Resin - Consituents And Properties

Question 1

Most composite resins are based on this product

Answer 1

Bis-GMA (addition product of bisphenol and glycidylmethacrylate) or urethane dimethacrylate + diluent monomer, triethylene glycol dimethacrylate (TEGMA)

Question 2

Products such as quartz, Fused silica, glasses such as aluminosilicate and borosilicate adds the following properties to the composite resin

Answer 2

Compressive strength, abrasion resistance, modulus of Elasticity,fracture toughness, thermal expansion, single contraction,aesthetic qualities

Question 3

Contains particles of radiopaque barium or strontium Glass 2.5- 5 micrometres in size to give 75 to 80% by weight of filler.
Mechanical properties are good but hard to polish and soon Roughens

Answer 3

Macrofilled or conventional

Question 4

Contains colloidal silica particles 0.04 micro meters in size and 30 to 60% by weight.
Retains a good surface polish that is unsuitable for load-bearing situations, has poor wear resistance and increase contraction shrinkage

Answer 4

Microfilled composite resins

Question 5

By combining Nanometric particles and nano clusters in conventional resin Matrixx, manufactures claim to offer increased wear resistance and polishability and Lustre

Answer 5

Nanofilled composite resins

Question 6

It contains a mixture of conventional and microfine particles designed to optimise both mechanical and surface properties.
Contains 75 to 85% by weight of filler, of which the bulk is conventional I.e 1 to 50 micrometers some manufacturers achieve up to 90% filler loadings by using blended size of filler particles

Answer 6

Hybrid composites

Question 7

These are developed to stimulate the condensation of amalgam although no decrease in volume as compressed therefore not strictly condensed.
Resin and ceramic fillers are incorporated into a network of ceramic fibres.
Claim to have increased wear resistance and less polymerisation shrinkage.

Answer 7

Packable (condensable)

Question 8

Chemically cured: benzoyl peroxide or sulfunic acid 

Answer 8

Initiator + tertiary amine activator

Question 9

Light cured: amine + diketone activated by this wavelength

Answer 9

Blue light 460-470 nm

Question 10

Classification

Answer 10

Microfilled
Posterior composite 
all-purpose 
flowable
condensable or packable

Question 11

Polymerisation shrinkage

Answer 11

1-4%

Question 12

Elastic modulus of this composite is greater than the other composite resins, amalgam

Answer 12

Hybrid

Question 13

Types of light source for curing

Answer 13

QTH, PAC, LED

LED WIDELY USED REPLACING QTH

Question 14

Products used to refine

Answer 14

Microfine diamond
Multibladed tungstun carbide finishing bur under water spray
Shofu points or finishing pastes for inaccessible areas

Question 15

The ratio of bonded to unbonded surfaces in a cavity. The higher this is, The more likely the risk of effects of polymerisation shrinkage leading to bond failure, cuspal deflection post-operative sensitivity.

Answer 15

C factor (configuration)

Question 16

They Allow command setting. They overcome the moisture sensitivity and low early mechanical strength associated with conventional GI.
The acid base reaction of GI is supplemented by the addition of 75% resin which is hydroxyethylmethacrylate bis GMA.
Used in deep carious lesions

Answer 16

RMGIC

Question 17

Poly acid modified resin.
Combines the adhesive and fluoride releasing properties of GI with the abrasion resistance of composite resin and it’s called with a touch of originality -
Used in pediatric patients

Answer 17

Compomer

Question 18

Composite resin with active GI filler particles

Answer 18

Giomers

Question 19

Organically modified ceramics

Answer 19

Ormocers

Question 20

They are similar to GIs except that the ion leachable glass is fused with fine silver powder. Mixing with a polymeric acid gives a cement consisting of unreactive glass particles with silver as fused, held together by a metal salt Matrixx with the benefit of increased wear resistance

Answer 20

Cermets

Question 21

Silanised monohybrid fillers embedded ina light curing organic matrix
Used in indirect onlays

Answer 21

Ceromers