Brainscape's Knowledge GenomeTM

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


See full index

MCQ 1.1 > Bases, Linings And Temporary Materials > Flashcards

Bases, Linings And Temporary Materials Flashcards

1
Q

What is a base in a cavity preparation

A

A material which is placed on the floor of the cavity preparation in a thick layer
Thermal insulation
Absorbing occlusal forces

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

What is a liner

A

A material placed in a thin layer over exposed dentine
Dentinal sealing
Stimulation to formation of irregular secondary (tertiary) dentine

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

What is a varnish

A

They seal dentinal tubules to reduce microleakage which may cause sensitivity, discolouration and bacterial invasion

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

What is calcium hydroxide Ca(OH)2

A

A dental liner which stimulates the formation of tertiary dentine
For direct or indirect pulp capping

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

What are 2 advantages of calcium hydroxide Ca(OH)2

A

Easily manipulated
Stimulates the formation of tertiary dentine

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

What are 2 disadvantages of calcium hydroxide Ca(OH)2

A

Moisture sensitive
Low strength

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

What is zinc oxide eugenol used for

A

When the decay is very deep or very close to the pulp chamber

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

What are 4 advantages of zinc oxide eugenol

A

Good dimensional stability
Good surface detail reproduction
Inexpensive
Adheres week to dental compound

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

What is a disadvantage of zinc oxide eugenol

A

Soft tissue irritant

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

What are 3 advantages of zinc oxyphosphate

A

Easy to manipulate
Economic
The excess material is removed easily

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

What are 3 disadvantages of zinc oxyphosphate

A

Not aesthetic
They account for the largest cases of micro filtration
Speed with the preparation of the mixture

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

What is an advantage of zinc polycarboxylate

A

Presents chemical adhesion to the dental structure

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

What are 3 disadvantages of zinc polycarboxylate

A

Work time is much shorter
pH of the liquid is 1.7 which is neutralised by the powder
The cement does not bond with noble metals when the model or vacuum is contaminated

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

What are 3 examples of temporary materials which will last 3-4 days

A

Zinc oxide eugenol
Zinc oxyphosphate
Zinc polycarboxylate

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

What are 3 examples of temporary materials which last 6 months

A

GICs
RMGICs
Compomers

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

What are 2 key features of GICs

A

They can bond to enamel and dentine
They release fluoride from the glass component of the cement

17
Q

What are GICs composed of

A

Glass
Polyacid
Water
Tartaric acid

18
Q

What are the 3 main components of GIC glasses

A

Silica
Alumina
Calcium fluoride

19
Q

Why is the glass composition limited to the central region of the phase diagram for GICs

A

To maintain translucency

20
Q

What does tartaric acid do

A

Affects the working and setting times of GICs

21
Q

What are the 3 stages of the GIC setting process

A

Dissolution
Gelation
Hardening

22
Q

What happens during dissolution of GICs

A

The solution or water mixed with powder causes the acid to dissolve and react with the outer glass layer leaving a silica gel

23
Q

When does final translucency and colour become apparent after GIC placement

A

24 hours

24
Q

How long does it take for a GIC to fully physically and mechanically set

A

1 month later

25
Q

What happens during gelation of GICs

A

Initial GIC is set due to calcium ions reacting with acid carboxyl groups

26
Q

What happens during the hardening phase

A

Aluminium ions after 30 mins provide final strength via strong cross linking
Water binds to silica gel around glass particles
Glass particles in silica gel within the cross linked polyacrylic acid matrix

27
Q

What are resin modified GICs (RMGICs)

A

Are hybrid glass ionomers primarily functioning as glass ionomer cements with a small amount of added resin typically hydroxyethylmethacrylate (HEMA)

28
Q

What are 4 disadvantages of GICs

A

Low early strength
Susceptibility to erosion
Slow setting phase
Risk of desiccation

29
Q

What are 6 advantages of RMGICs

A

Command set by visible light
Between wear resistance
Lower solubility
Early high compressive and flexural strength
Good polishability
Ability to retain polish

MCQ 1.1 (43 decks)

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