CSA clinical aspects of GIC

Question 1

What is traditional glass ionomer cement?

Answer 1

powder Calcium-Fluoro-Alumino-Silicate Glass and Poly Alkenoic acid.

Question 2

What is most common polyalkenoic acid?

Answer 2

polyacrylic acid , as well as polymaleic and polyitaconic acid

Question 3

What are all polyalkenoic acids?

Answer 3

Long hydrocarbon chain backbone

Question 4

What does Glass contain?

Answer 4

calcium fluoride and aluminium fluoride can be displaced in acid

Question 5

What is the setting reaction?

Answer 5

• water added to powdered glass and poly acid, paste is created
• takes several hours to reach its final strength.

Question 6

What are 3 phases to setting reaction?

Answer 6

dissolution
gelation
hardening

Question 7

What is dissolution ?

Answer 7

H20 added to dry components, H+ liberated from COOH groups on polyacid chains

Question 8

What happens when H+ ions in dissolution come into contact with glass particles?

Answer 8

attack glass causing Ca, Al, F, ions to be released from glass and go into solution

Question 9

What is process of gelation?

Answer 9

• Ca2+/Al3+ attracted to negatively charged carboxyl groups on acid chains.
• causes chains to link together.

Question 10

What is process of hardening?

Answer 10

up to a week before material reaches final hardness and several months before full maturation.

Question 11

Why must traditional GIC protected by layer of varnish for first week?

Answer 11

materials prone to lose ions not yet reacted with acid chains if restoration gets too wet –ions leak out into saliva and material never reach a good strength.

Question 12

What are fluoride ions from CaF and AlF remain as?

Answer 12

unreacted and move through material into surrounding tooth

Question 13

What does unreacted Fluoride impart?

Answer 13

anticariogenic effect on enamel and dentine adjacent to GIC

Question 14

What is fluoride recharge?

Answer 14

New fluoride enter GIC from toothpaste and topical fluoride application

Question 15

Is amount of fluoride release from GIC enough ?

Answer 15

doesn’t prevent caries in high risk or reverese deep carious lesions after formed

Question 16

How do GIC bond to teeth?

Answer 16

adhere directly to enamel and dentine without need for a bonding agent.

Question 17

Do gic bond stronger to enamel or dentine?

Answer 17

ENAMEL since more min. content here

Question 18

What is freshly cut tooth surface covered by ?

Answer 18

smear layer- loosely bound debris GIC would bond weakly,

Question 19

How to remove smear layer?

Answer 19

using polyacrylic acid prior to placement of the GIC.

Question 20

What does polyacrylic acid do?

Answer 20

doesn’t etch dentine leaving exposed collagen fibres, removes smear leaving a clean dentine surface.

Question 21

Are GIC water based?

Answer 21

tolerate wet enviro. compared to composites

Question 22

Why is GIC used for subginigival restorations?

Answer 22

tolerate wetter enivro. but can’t bond to a tooth wet with saliva or blood

Question 23

What does tradiotional glass ionomer not have?

Answer 23

translucency, surface polish or good shade match so use composites

Question 24

Where is GIC used

Answer 24

Anteriorly

Question 25

What are the advantages of traditional GIC?

Answer 25

- chemical adhesion to tooth, - ability to bond where moisture control for composite cannot be achieved - release of fluoride.

Question 26

What are main disadvantages of GIC?

Answer 26

- aesthetics being not as good | - strength not as good as composite or amalgam

Question 27

What was the 1985 silver cermet?

Answer 27

addition of amalgam powder (AG3SN) to GIC before mixing it.

Question 28

What was the RESIN MODIFIED GIC?

Answer 28

HEMA to GIC, or grafting polymerisable groups to the poly acid chains,

Question 29

Advantages of RMGIC?

Answer 29

- stronger, sets on command (light curing) and more resistant to losing Al and Ca ions during hardening . - improved aesthetics and translucency.

Question 30

What does resin mattrix formed not allow?

Answer 30

much ion movement so no varnish protection no ions can be lost.

Question 31

What is biggest disadvantage of RMGIC?

Answer 31

fluoride ions cannot move so freely either,

Question 32

Cna GIC set chemically in absecnce of light?

Answer 32

yes

Question 33

Can RMGIC be light cured?

Answer 33

yes would speed up but eventually fully set chemically, so used for bonding amalgam which not allow light reach material.

Question 34

What is the 2012 zinc reinforcement ?

Answer 34

substitution of Ca ions with Zinc ions. | - resulting material is stronger, more wear resistant and higher fracture toughness than all other types of GIC

Question 35

What do 50% of GIC fail?

Answer 35

secondary caries

Question 36

When is GIC used in cavities when no other material usable ?

Answer 36

patients with limited opening, difficult access, not able to properly dry, quick fix when patient is anxious.

Question 37

What is life expectancy of GIC like compared to amalgam and composite ?

Answer 37

SHORTER

Question 38

Cavity prep for GIC?

Answer 38

REMOVE smear layer | - brush 10% polyacrylic acid to surfaces of cavity for 10 seconds, rinse well and drying for 10 seconds.

Question 39

What should cavity be like for gic since it doesnt flow well?

Answer 39

smooth surfaced cavity with slow speed bur | DO NOT BEVEL

Question 40

How does capsule come with GIC?

Answer 40

correct amounts of powder and water

Question 41

How is GIC placed?

Answer 41

directly using matrix strip or band to prevent overhangs interproximally

Question 42

why not to use metal matrix band with GIC

Answer 42

can adhere firmly to metal and pulled out cavity when band removed.

Question 43

Why do we need to work quick with GIC?

Answer 43

SETTING STARTS AFTER MIXING

Question 44

how do we need to feel if material is sluggish?

Answer 44

don’t use instruments as fractures within material and pulling away from cavity walls.

Question 45

What do we coat gic with?

Answer 45

resin bond (Optibond solo is fine) and light cure.

Question 46

What is prep for RMGIC?

Answer 46

shape as you would for composite. - Delay light curing - restoration can be finished and polished immediately after - No moisture protection is required.

Question 47

What are clinical indications for traditional GIC?

Answer 47

``` • Cavities extending below the CEJ • Temporisation (DURING) Endodontics • Caries Management • Stepwise excavation • Paediatric restorations • Luting Cement for crowns - Fissure sealant ```

Question 48

What are clinical indications for RMGIC?

Answer 48

• Cavities extending below the CEJ | -• Lining / Bonded amalgam

Question 49

Why should RMGIC not be used for dentine bonded crowns or cementing posts?

Answer 49

expansion during setting that could fracture restoration or tooth