Resin (5)

Question 1

Ideal properties of Provisional Restorative materials

Answer 1

Ease of formation
Promotes oral health
Esthetic appearance
Stable and Durable

Question 2

What are the advantages of Resin-based restorative materials?

Answer 2

Relative ease of formation
Some translucency
Thermally and electrically insulating

Question 3

What are the disadvantages of Resin-based restorative materials?

Answer 3

Exothermic rxn
Polymerization shrinkage
Variable polymerization efficiency
High coefficient of thermal expansion on heating
Low toughness

Question 4

What happens if the resin polymerization doesn’t go to completion?

Answer 4

It will be less durable

Question 5

What is the formation rxn of resin polymer?

Answer 5

Monomer + filler + active initiator = filled polymer

Question 6

What are the categories of polymers?

Answer 6

Thermoplastic

Thermoset

Question 7

Thermoplastic

Answer 7

No cross-linking
Physical state is reversibly controlled by temperature
i.e. wax

Question 8

Thermoset

Answer 8

Transformation form monomer to polymer involves irreversible cross-linking

Question 9

Monomer

Answer 9

Molecule capable of covalent bonding with another monomer

Question 10

Polymer

Answer 10

Molecule formed from many monomers

Question 11

Co-polymer

Answer 11

Polymer formed from two or more monomers

Question 12

What are the mechanisms of polymerization or setting

Answer 12

• Addition polymerization releases no by-products

- Condensation polymerization results in a by-product

Question 13

What is the exclusive polymerization method for most current dental restorative resins?

Answer 13

Free-radical polymerization

Question 14

What physical phenomenon occurs during polymerization

Answer 14

Changes from a liquid to a solid

Question 15

What are the chemical stages of polymerization?

Answer 15

• Activation of initiator
• Activation of monomer
• Polymer growth
• Termination

Question 16

What are the types of initiator activation?

Answer 16

Heat activation
Chemical activation
Light activation

Question 17

Heat activation of an initiator

Answer 17

Highly efficient
Uniform
Large working time
Requires mixing of initiator and monomer
Requires heating equipment

Question 18

Chemical activation of initiator

Answer 18

Chemical activator is packaged with monomer and mixing is required
Working time is fixed by the chemistry
This is not was efficient heat activation, but heat can increase efficiency

Question 19

Light activation of initiator

Answer 19

All ingredients can be mixed by the manufacturer
Working time is practically infinite, but is diminished by ambient blue light
Intense light is required for efficiency - blue light is diminished by tooth colored materials, especially those that are darker

Question 20

Activation of monomer

Answer 20

The change of a double bond to two single binds releases the heat of a reaction

Question 21

Growth of active polymer

Answer 21

Active polymer spontaneously combines with more monomer
The heat of reaction whats the material
The density increases
Monomers with dual functionality cause cross-linking between two growing polymers

Question 22

The greater the size of the methacrylate monomer…

Answer 22

• the less shrinkage
• the less heat of the run
• the lower the mechanical properties of the set resin

Question 23

What are the physical state changes that occur during polymer growth?

Answer 23

1. Liquid/Sandy
2. Stringy
3. Doughy
4. Rubbery
5. Solid

Question 24

Termination

Answer 24

2 active polymers can combine

Free radical transfer causes a growing to stop growing while activating a single monomer

Question 25

What contaminants can cause early termination?

Answer 25

Oxygen Sulfur Eugenol Hydroquinone

Question 26

What is the general composition of dental resins?

Answer 26

Monomer and the activation system becomes the polymer matrix | Filler particles

Question 27

What are the types of filler

Answer 27

Organic | Inorganic

Question 28

Organic filler

Answer 28

Soluble in the monomer

Question 29

Inorganic filler

Answer 29

Requires a silane bonding agent to chemically bond to the polymer matrix But it provides better mechanical properties of the set composite

Question 30

How can an ideal material promote oral health?

Answer 30

Protect remaining tooth structure Maintain periodontal health Provide occlusal stability Maintain tooth position

Question 31

What are the types of resin?

Answer 31

PMMA PR'MA Bis-acrylate (Bis-GMA) Urethane DMA

Question 32

Which resin materials provide the most desirable marginal adaptation during the Indirect Technique?

Answer 32

``` Duralay (PMMA) Protemp Garant (Bis-GMA) ```

Question 33

Which resin materials provide the most desirable rise in temp during reaction?

Answer 33

``` Protemp Garant (Bis-GMA) Trim (PR'MA) ```

Question 34

Which resin materials provide the most desirability of Toxicity and Allergenicity?

Answer 34

``` Protemp Garant (Bis-GMA) Triad (Urethane DMA) ```

Question 35

Which resin materials provide the most fracture toughness?

Answer 35

Triad | Jet

Question 36

Which resin materials provide the most desirability of odor?

Answer 36

Triad | Protemp Garant