Water/Oil Based Cements

Question 1

What is a big advantage of polymer based cements over traditional water based cements?

Answer 1

polymer cements bond to tooth structure while water based do not

Question 2

give some examples of traditional cements

Answer 2

• zinc oxide- eugenol (oil based)
• zinc phosphate (water based)

Question 3

give some examples of polymer based cements

Answer 3

• polycarboxylate
• glass ionomer
• resin modified glass ionomer
• composite resin

Question 4

give examples of temporary filling material

Answer 4

• ZOE
• silicophosphate
• glass ionomer

Question 5

give examples of durable filling material

Answer 5

• glass ionomer
• silica

Question 6

give examples of cavity liner or base

Answer 6

• ZOE
• glass ionomer

Question 7

give examples of cementation

Answer 7

• all but silicate cement

Question 8

Properties we want in cements

Answer 8

• low or no coefficient of thermal expansion
• low thermal conductivity
• compressive/tensile/bond strength
• insoluble
  -adequate working time
• short setting time
• resistance to dislodging forces
• adequate flow
• adhesive
• resist plastic deformation/high elastic modulus
• not sedative
• anticariogenic
  -transluecent
• thin film thickness
• non toxic
• easy to clean up

Question 9

What is one of the most important properties of cements?

Answer 9

solubility
- don’t want it to be soluble because premature contact with water/saliva results in leaching of surface

Question 10

What should be applied to vital tooth to avoid irreversible trauma to pulp?

Answer 10

calcium hydroxide or varnish

Question 11

What is controlled by the operator affecting the rate of set of zinc phosphate cement:

Answer 11

• power/liquid ratio (more powder= faster)
• rate of power incorporation/mixing (faster mixing= faster)
• mixing temperature (increase temp= faster)
• manner of spatulation/mixing (faster mixing= faster)

Question 12

Downsides of zinc phosphate cement:

Answer 12

• most rigid
• irritant (due to acidity)
• no adhesion
• no anti-bacterial properties
  good because insoluble

Question 13

Which cement is not used

Answer 13

zinc silicophosphate cement

Question 14

What is often used at ULSD for temporary material?

Answer 14

zinc oxide eugenol
- temporary because soluble

Question 15

In zinc oxide powder cement, what does rosin do?

Answer 15

reduce brittleness

Question 16

In zinc oxide powder cement, what does zinc stearate do?

Answer 16

plasticizer

Question 17

In zinc oxide powder cement, what does zinc acetate do?

Answer 17

increase strength and setting reaction

Question 18

In zinc oxide liquid cement, what does olive oil do?

Answer 18

plasticizer

Question 19

What was added to zinc oxide eogonel to try to make it less soluble and more of a permanent material? (didn’t work)

Answer 19

polymethyl methacrylate

Question 20

Setting reaction of zinc oxide-eogonel

Answer 20

chelate rxn forming a ring as a result

Question 21

Difference in powder/liquid ratio manipulation of zinc phosphate and zinc oxide:

Answer 21

• zinc phosphate: small quantities added at a time
• zinc oxide: large amount of powder can be added by heavy spatulation

Question 22

Which requires a cool slab for mixing?

Answer 22

• zinc phosphates
• zinc polycarboxylate

Question 23

Which material is so thick it makes the flow deceptive?

Answer 23

zinc oxides

Question 24

Some properties of zinc oxide:

Answer 24

• long working/setting times
• low strength
• high solubility (won’t last longer than 6 weeks)
• good sealing properties

Question 25

Which material is an obtundant material?

Answer 25

zinc oxide eugenol

Question 26

Which material inhibits set of resin?

Answer 26

zinc oxide eugenol

Question 27

Which material is very acidic and can cause irreversible trauma to pulp making it best to apply calcium hydroxide or varnish to vital dentin?

Answer 27

zinc phosphate