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26 Cards in this Set
- Front
- Back
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What is the film thickness requirement for cement?
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25 um
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What is the ADA recommended setting time for cements?
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5 to 9 min
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What is the ADA recommended compressive strength for cements?
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68.7 Mpa
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What is the ADA recommended solubility for cements?
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0.2%
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What is another name for oil based cements?
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eugenol (cinnamon, sage, sloves)
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What are 3 applications for ZOE cements?
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1. temporary cements
2. dentin linings 3. temporary filling materials |
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What is the process called that converts ZnO + eugenol --> Zn Eugenolate + ZnO?
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chelation
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What are 2 trends for ZOE? As compared to what?
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increased solubility, decreased compressive strength
As compared with zinc phosphate |
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What are 3 biological effects of ZOE?
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-bland/obtundent effect on pulp tissue when used as a base in a deep cavity
- irritant effect when placed directly on connective tissue - causes necrosis when placed directly on pulp |
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What does ZOE inhibit? What does this mean?
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inhibits free radical polymerization; prevents the setting of composite/bonding systems
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What are 2 advantages of ZOE?
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- bland effect on pulp
- good sealing ability |
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What water-based cement do we nolonger use because it causes lots of sensitivity? What does it contain?
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silicate cements; contains phosphoric acid and alumino-silicate glass
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What do glass-ionomer cements contain?
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alumino-silicate glass and polyacrylic acid
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What do zinc phosphate cements contain?
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zinc oxide and phosphoric acid
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What do zinc polycarboxylate cements contain?
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zinc oxide and polyacrylic acid
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What is the oldest of the permanent luting cements?
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zinc phosphate; can also be used as a base under restorations
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What are 2 modifications of zinc phosphate cements?
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- copper cements
-- cupric oxide (CuO) is black -- cuprous oxide (Cu2O) is red - fluoride -- 1-3% stannous fluoride |
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What is the comparative solubility and strength of zinc phosphate fluoride cements?
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higher solubility
lower strength |
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How do you mix phosphate based cements?
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add power in small portions, dissipate heat of reaction by mixing, do not disturb mixed cement until set
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What is the appearance of silicophosphates like?
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greater translucency; useful for cementation of porcelean restorations
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What are 4 disadvantages of zinc phosphate cement?
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pulpal irritation
marginal leakage/lack of adhesion solubility in organic acids/oral fluids brittleness |
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What are 4 advantages of zinc phosphate cement?
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long history
handles easily high compressive strengths low film thickness |
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What is an example of a Polycarboxylate cement?
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Duralon
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What are 2 applications of polycarboxylate cements?
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cementation of restorations and orthodontic;
retrievability as compared to other cements? |
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What is the manipulation of polycarboxylate cements like?
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need to mix on a cool slab; mix rapidly,
more viscous than zinc phosphate |
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What is the compressive strength like for polycarboxylate cements?
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compressive strength is a little low for a permanent cement
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