3/11: Types of Cement and Their Uses

Question 1

What are types of cements?

Answer 1

Zinc phosphate
Zinc oxide eugenol
Zinc polycarboxylate
Glass ionomer
Resin-modified glass ionomer
Provisional cements

Question 2

Note that no cement will perform to it’s optimal level clinically without an ______________________ that includes good resistance and retention form

Answer 2

Adequate preparation

Question 3

What are characteristics of cements?

Answer 3

Biocompatibility
Retention
Mechanical properties - withstand occlusal forces, high tensile strength
Marginal seal
Low film thickness
Ease of use
Radiopacity
Esthetics

Question 4

What is the first cement appearing in dental literature?

Answer 4

Zinc phosphate

Question 5

What cement is the standard which other cements are assessed?

Answer 5

“gold standard”
Zinc phosphate

Question 6

What are advantages of zinc phosphate?

Answer 6

Thin film thickness and proven reliability
Low solubility which resists breakdown in the mouth
Low thermo-conductivity - provide less sensitivity to hot and cold
Long shelf life

Question 7

What are disadvantages of zinc phosphate?

Answer 7

Initial low pH- can lead to pulpal irritation
No chemical adhesion/bond
No antibacterial properties
Poor esthetics (for all porcelain)
Long setting time: 2.5-8 minutes
Exothermic - chill glass slab when mixing, small amounts of powder added to liquid

Question 8

What are two types of Zinc oxide eugenol (ZOE) cement?

Answer 8

Type I
Type II

Question 9

How do the two types of ZOE differ?

Answer 9

In their properties and uses

Question 10

Describe type I ZOE

Answer 10

Less strong and used for temporary restorations and for temporary cementation (temp-bond)

Question 11

Describe type II ZOE

Answer 11

Reinforced and stronger
Last for 6-12months in the mouth
Used for a tooth that cannot ber estored immediately (IRM)

Question 12

What cement is referred to as an intermediate restoratie?

Answer 12

Type II ZOE

Question 13

What is the benefit of ZOE?

Answer 13

Neutral pH
Has a sedative or soothing effect on the dental pulp
!A protective or insulating base or liner is not required

Question 14

When is ZOE not used?

Answer 14

Under composite or acrylic restorations because eugenol is incompatible with these materials and retards their setting process

Question 15

What determined whether the powder is incorporated into the liquid in increments or all at once?

Answer 15

The type adn intended use

Question 16

What is the mixing/setting time of ZOE?

Answer 16

Mixing: Usually 30-60 sec
Setting: 3-5 min

Question 17

When and why was zinc polycarboxylate developed?

Answer 17

1968 - to circumvent pulpal problems associated with low pH

Question 18

What was the first cementing system to obtain an adhesive agent that bonded to enamel and dentin?

Answer 18

zinc polycarboxylate

Question 19

What kind of action does zinc polycarboxylate have?

Answer 19

Antibacterial

Question 20

Describe the working/mixing time of zinc polycarboxylate

Answer 20

Mixing- 30-40 sec
Working- 2.5min

Question 21

What powder is incorporated in large quantities?

Answer 21

polycarboxylate

Question 22

What cement isn’t as fragile as zinc phosphate?

Answer 22

polycarboxylate

Question 23

What poor characteristic does polycarboxylate have?

Answer 23

Poor marginal sesaling due to film thickness
- rubbery

Question 24

What doesn’t the polycarboxylate support?

Answer 24

Occlusal stress as well as newer cement
- sometimes use it in temporary circumstances

Question 25

What does/does not polycarboxylate bind to?

Answer 25

Most alloys but NOT gold

Question 26

Is polycarboxylate difficult to remove excess?

Answer 26

Yes (Rubbery)

Question 27

What cement bonds well to enamel/dentin but it's use has lessened over the years?

Answer 27

polycarboxylate - can be used as permanent, but there are better ones out there. It's used as a long term temporary cement or a short term clinical crown

Question 28

What is glass ionomer cement known as?

Answer 28

Acid-base cement

Question 29

What is part of the success of glass ionomer cement?

Answer 29

Their performance is good even if they have not been properly mixed

Question 30

What is the film thickness of glass ionomer cement?

Answer 30

Very thin film thickness

Question 31

What cement is extremely moisture tolerant but fairly soluable?

Answer 31

Glass ionomer

Question 32

What is an important advantage of glass ionomer cement?

Answer 32

Fluoride release It can be sustained for long periods of time

Question 33

What can affect film thickness?

Answer 33

Working time - longer working times allow more flow and will aid in seating the restoration

Question 34

It's important that mixing and placement of the cement is completed within ________ minutes

Answer 34

2-2.5

Question 35

When and why were modified glass ionomers created?

Answer 35

Early 1990s to overcome the high solubility of glass ionomers

Question 36

What do modified glass ionomers have added?

Answer 36

Hydrophillic methyacrylate monomers

Question 37

What are the benefits/advantages of glass ionomers?

Answer 37

Same benefits of glass ionomer cements

Question 38

What are disadvantages of modified glass ionomers?

Answer 38

Low early strength and moisture sensitivity during setting

Question 39

How long does it take for modified glass ionomers to set?

Answer 39

24 hours for the final set

Question 40

What is the key role of provisional/temporary cements?

Answer 40

Keeping the temporary restoration on the tooth while the patient is waiting for the final restoration to return from he lab

Question 41

What cement needs to be easily removed from prepared tooth without harming periodontum, tooth preparation, or pulp?

Answer 41

Provisional/temporary

Question 42

Most provisional/temproary crowns have?

Answer 42

Eugenol (ZOE) - although eugenol can have a negative effect on acrylic resins and composite resin cements

Question 43

What affect does eugenol provide for temporary cements?

Answer 43

Antibacterial effect

Question 44

What are examples of temporary cements?

Answer 44

Temp-bond Ultra temp Relyx temp

Question 45

What should you consider when selecting temporary cements?

Answer 45

How long How retentive What will permanent cement be Working in esthetic zone