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1

changes in -- produces dimensional change of dental materials

temp

2

excessive contraction -->

microleakage and secondary caries

3

excessive expansion -->

pressure on pulp, post-operative sensitivity, restoration protrudes

4

force per unit area

stress

5

unit of stress

N/m^2 (Pa)

6

when stress exceeds the -- of an object, object breaks

cohesive strength

7

stress =

force/ cross-sectional area

8

Force (N) = 111, Stress (MPa) = 172.4

(mm^2) = 0.645 Area

9

elastic limit or yield strength/point: the max stress a material can withstand without --

permanent deformation

10

tipping point between elastic and plastic strain

elastic limit or yield strength/point

11

current flow by a -- between two dissimilar metals in contact in a solution

voltage difference

12

Galvanic corrosion, Al --

dissolves (corrodes)

13

Al forms --

anode

14

Copper is less likely to --

corrode

15

copper forms --

cathode

16

the greater the difference in voltage -->

greater current flow

17

anode in mouth

amalgam

18

cathode in mouth

gold

19

electrolyte in mouth

saliva

20

what kind of metal corrodes?

more active (more base)

21

what kind of metal resists corrosion?

less active (more noble)

22

pain sensation by electric current generated in a galvanic cell

galvanic shock