Glass Ionomer Cements Flashcards Preview

BDS2 CLINICAL Dental Materials > Glass Ionomer Cements > Flashcards

Flashcards in Glass Ionomer Cements Deck (74)
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1

what are the 2 types of glass ionomer

conventional
resin modified glass ionomer

2

what are the 2 types of conventional glass ionomer

anhydrous
original

3

what are the 2 types of RMGI

self cure
light cure

4

what is GI used in

restorative
core build up
lining
luting for cementing indirect restorations

5

when is GI used as a filling material

often in children's teeth
sometimes in adults if in a non-load bearing area e.g cervical

6

what are names of GI used as filling materials

riva
vitremer

7

when is GI used for a core build up

prior to a restoration with a crown

8

what is the name of the GI used for core build up

vitremer crown core

9

what are examples of GI used for linings

vitrebond, ionoseal

10

what are examples of GI used for luting

Fuji Luting
Vitremer luting cement
Aquachem

11

what two materials did GI originate from

zinc polycarboxylate cement
silicate cement

12

what is silicate cement

n anterior filling material based on fluoro-alumino-silicate glass combined with phosphoric acid

13

what properties did mixing silicate cement and zinc polycarboxylate cement result in

resulted in a fluoride releasing filling material (from the silicate material) which had the ability to bond to tooth structure (from the carboxylic acid material

14

what are the two components of GI cements

acid (liquid)
base (glass powder)

15

what are the two acids present in GI cement

poly acrylic acid
tartaric acid

16

what is polyacrylic acid

ionic monomer
usually copolymers of acrylic and itaconic acid or acrylic and malice acid

17

what is tartaric acid used for

added to control the setting characteristics of the material

18

what does the base consist of

silica, SiO2 (silicone dioxide)
alumina, Al2O3 (aluminum dioxide)
calcium fluoride
aluminium fluoride
aluminium phosphate

19

what does adding strontium and lithium salts to the powder do

increase the radiopacity but these play no part in the reaction chemistry

20

what does the ratio of alumina/silica affect

translucency
more silica = more translucent

21

what are the variations in the composition

material may be anhydrous or encapsulated
there can be significant variations in the composition of the powder
the molecular weight of the acid can change

22

what are anhydrous material GI

the acid is freeze dried and added to the powder and the liquid is distilled water.

23

what is the advantage of having anhydrous GI

This makes for easier handling of the material, particularly mixing as polyacrylic acid is not an easy material to mix with so now we have an anhydrous material.

24

what is the advantage of encapsulated materials

consistent powder/liquid ratio. The proportions are set and controlled by the manufacturer and mixing is a quick and clean process as it goes in an amalgamator. It is therefore easier to use. It should therefore have more consistent properties of the mixed material.

25

what are the variations in the composition of the powders

Powder particle size can vary

26

what does a bigger particle size lead to

The bigger the particle, the better the aesthetic especially if it is larger silica particle

27

if the material is a luting agent what should the particles be

particle size has to be smaller than 20 micrometres to give a low film thickness and to not interfere with the restoration you are cementing.

28

how does particle size effect the setting reaction

The smaller the particle size the quicker the setting reaction and the opaquer the set cement.

29

what does a higher molecular weight acid have an effect on

Generally, the higher the weight (the longer the acid chain) the better the mechanical properties of the set material.
However the higher molecular weight acids are viscous and difficult to mix (liquid is less liquid) so need to find a balance.

30

what type of reaction is the setting reaction of GIC

acid/base