Chapter 1 2

Question 1

Galvanism

Answer 1

An electrical current transmitted between two dissimilar metals in a solution of electrolytes

Question 2

Interface

Answer 2

The surface between the walls of the preparation and the restoration or between two dental materials

Question 3

Tarnish

Answer 3

Discolouration resulting from oxidation of a thin layer of a metal at its surface. It is not as destructive as corrosion

Question 4

Compressive force

Answer 4

Force applied to compress or squeeze an object; crushing biting forces. Must common for posterior teeth

Question 5

Tensile force

Answer 5

Force applied in opposite directions to stretch an object or pull it apart

Question 6

Shearing force

Answer 6

Force applied when two surfaces slide against to each other in opposite directions when the max and mand incisors are used for cutting shearing forces are applied

Question 7

Torsion or torque

Answer 7

Twisting force that has tensile and compressive forces.
When a patient wears full dentures he or she may complain that the dentures become dislodged when they chew certain foods. This is because of torque on the dentures, which are not well suited to withstand the combination of compressive and tensile forces while eating

Question 8

Stress

Answer 8

The amount of force exerted from within an object

Question 9

Strain

Answer 9

The amount of change that the force has produced.

Question 10

Flexural stress also called bending stress

Answer 10

Is a combination of tension and compression.

Ex: dental bridges are subject to flexural stress when compressive forces placed on the occlusal

Question 11

Exothermic reaction

Answer 11

The production of heat resulting from the reaction of the components of some materials when they are mixed

Question 12

Percolation

Answer 12

Movement of fluid in the microscopic gap of a restoration margin as a result of differences in the expansion and contraction rates of the tooth and the restoration with temperature changes associated with ingestion of cold or hot fluids or foods

Question 13

Corrosion

Answer 13

Deterioration of a metal caused by a chemical attack or electrochemical reaction with dissimilar metals in the presence of a solution containing electrolytes (such as saliva)
Amalgam is very susceptible to corrosion causing marginal breakdown

Question 14

Coefficient of thermal expansion

Answer 14

The measurement of change in volume or length in relationship to change in temperature

Question 15

ADA

Answer 15

American dental association

Question 16

Auxiliary materials

Answer 16

Materials used to fabricate and maintain restorations, directly or indirectly.
Ex: impression materials, gypsum, dental waxes, finishing polishing materials

Question 17

Wetting

Answer 17

The ability of a liquid to wet or intimately contact a solid surface. Water beading on a waxed car is an example of poor wetting

Question 18

Film thickness

Answer 18

The minimal obtainable thickness of a layer of a material. It is particularly important in the context of dental cements

Question 19

Chroma

Answer 19

Refers to the intensity or strength of the colour; teeth are rather pale in colour

Question 20

What is the best restoration material that has the closest CTE value closest to natural teeth

Answer 20

Gold! Gold is one of the best thermal conductors even better than amalgam

Question 21

Value

Answer 21

Describes how light or dark the colour is. Teeth have value ranges at the light end of the value scale

Question 22

What are the three types of primary bonds are known:

Answer 22

Ionic bonds, covalent bonds, metallic bonds

Question 23

Opaque

Answer 23

When the light is completely absorbed by the object

Question 24

Metamerism

Answer 24

Colours look different under different light source

Question 25

Inlay

Answer 25

Inlay does not involve the cusps

Question 26

Onlay

Answer 26

Onlay covers cusps bigger

Question 27

Overlay

Answer 27

Medial distal

Question 28

What do you want to see in an alginate impression

Answer 28

Palate, teeth, hard palate, soft palate, mucobuccal fold, retromolar pad , gingiva

Question 29

Hydrocolloids

Answer 29

Are water based colloids that function as elastic impression materials

Question 30

Two types of hypocolloids

Answer 30

Reversible, irreversible

Question 31

What is the composition of alginate

Answer 31

Sodium alginate, calcium, sulfate dehydrate diatomaceous earth colorant inhibitors potassium sulfate, and trisodium phosphate
Trisodium phosphate is what makes it set fast

Question 32

Is alginate an reversible or irreversible hydrocolloid

Answer 32

Irreversible

Question 33

Criteria for good alginate impression

Answer 33

All teeth and alveolar processes peripheral roll and frenums no large void good reproduction of detail

Question 34

Overheating

Answer 34

Pressed tray to hard. You can see the tray through alginate.

Question 35

What has a catalyst and base impression material

Answer 35

Elastomeric material ( final impression material)

Question 36

When would you use a elastomeric material

Answer 36

When you need more accuracy. They can have different viscosities putty, heavy regular syringe or light bodies