Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BDS2.5 Dental Materials - operative dentistry > Plastic restorations - Resin modified glass ionomer cements > Flashcards

Plastic restorations - Resin modified glass ionomer cements Flashcards

1
Q

What is a resin modified glass ionomer?

A

it is close to a glass ionomer but has some resin it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 2 hybrid materials?

A

compomer and resin modified glass ionomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the advantages of resin based composites?

A

command set by visible light

better wear resistance

lower solubility

early compressive and flexural strength

good polishability

ability to retain its polish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the disadvantages of glass ionomer cements?

A

lower early strength

susceptibility to erosion

slower setting phase

risk detection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

is resin hydrophobic or hydrophilic?

A

hydrophobic effectively

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the constituents of RMGICS? (BASIC)

A

Are conventional glass ionomer cements and water-soluble resin and modified poly(acrylic acids)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are olyacrylic acids?

A

they have pendant methacrylate groups or methacryloxy groups grafted onto the polyacid chain (copolymers)

= copolymers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the resin group?

A

usually HEMA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the glass ionomer part?

A

polyacid

tartaric acid

water

ion leachable glass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the resin part?

A

water soluble (miscible) monomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What us HEMA?

A

SMALL HIGHLY REACTOVE MONOMER MOLECULE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Is glass ionomer hydrophobic or hydrophilic?

A

hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What connects the hydrophobic resin composite and hydrophilic GI?

A

HEMA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the problem with HEMA?

A

it is a powerful dermatological sensitizer causing chemical dermatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What form is HEMA a hazard?

A

in the unset form, after polymerisation it is fine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What will happen f the level of HEMA polymerisation is low?

A

then unconverted monomer can leach out as polyHEMA which absorbs water very quickly

17
Q

What is the effect of freed HEMA monomer?

A

move into surrounding dental hard and surrounding tissues

may potentially have toxological effects on the dental pulp and osteoblasts if polymer degrades

18
Q

How does RMGIC decrease microleakage?

A

it seals the dentinal tubules opened during cavity preparation and decreases the risk of microleakage

decrease microcontamination

19
Q

What are the constituents of RMGIC? (powder)

A

Barium, strontium or aluminosilicate glass

vacuum-dried polyacrylic acid

potassium persulphate

ascorbic acid

pigments

20
Q

Why use barium, strontium or aluminosilicate glass? (powder)

A

improved strength

imparts radiopacity

21
Q

What reaction makes the poly salt matrix? (powder)

A

vacuum-dried polyacrylic acid and glass

22
Q

What provides the chemical cure (powder)

A

potassium persulphate

ascorbic acid

23
Q

What are the chemical constituents? (liquid)

A
24
Q

What does polyacrylic acid react with (liquid)?

A

reacts with the glass to form the poly salt matrix

25
Q

What does the copolymer do (liquid)?

A

ability to undergo both acid-base and polymerisation reactions

helps form interpenetrating network (the set)

26
Q

What is the polymerisation reaction due to?

A

resin

27
Q

What is the acid-base reaction due to?

A

Glass ionomer

28
Q

What sharpens the acid-base reaction set? (liquid)

A

tartaric acid

29
Q

What is the role of water in RMGIC? (LIQUID)

A

permits reaction between the polyacid and the glass

30
Q

What happens to translucency as particle size is reduced?

A

as particle size is reduced there is a progressive loss in translucency (gets more opaque)

31
Q

What reaction does the water-miscible monomer permit?

A

polymerisation reaction

32
Q

What else happens during the polymerised resin phase?

A

it forms a scaffolding while the ionomer cement matrix is being formed

33
Q

What happens as the resin content is increased?

A

the acid-base reaction is slowed

as the resin matrix decreases the motility of the other ions to form the chemical reaction

34
Q

When is the effect of the resin addition primarily seen?

A

during the initial stages of the set when the glass ionomer cement is weakest

35
Q

Why does the resin need to be soluble in water?

A

as the cement remains water based

36
Q

What happens if there is an absence of water?

A

there is no reaction between the polyacid and the glass

37
Q

Why is there a limit in the number of resin systems used in the material?

A

due to its hydrophobicity

38
Q

What 2 types of setting reaction stake place in the material?

A

acid-base

polymerisation

BDS2.5 Dental Materials - operative dentistry (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions