Quiz #2 Dent Mat

Question 1

3 oral environment factors to take into consideration

Answer 1

temp changes
corrosive environment
mechanical stresses

Question 2

what are 3 types of primary bonds

Answer 2

ionic
covalent
metallic

Question 3

what is a type of secondary bond

Answer 3

van der waal forces

Question 4

what is found in van der waal forces

Answer 4

H bonds

Question 5

which primary bond is the strongest

Answer 5

covalent

Question 6

what do many ceramic dental materials consist of

Answer 6

ionic bonds

Question 7

what do polymeric materials consist of

Answer 7

covalent bonds

Question 8

what is a metallic bond

Answer 8

atoms are held together by interactions of valence electrons. however, the e are free to move throughout the solid bc the valence electrons are not bound b/w metal ions

Question 9

energy is transferred easily through what types of bonds

Answer 9

metallic bonds -> good metal conductivity

Question 10

can a material have 2 types of PRIMARY bonds?

Answer 10

yes

Question 11

how is the h bond created

Answer 11

by a permanent dipole that exists within asymmetric molecules

Question 12

what is an arrangement of atoms

Answer 12

crystalline structure

Question 13

what is a crystalline structure

Answer 13

a repeated consistent internal structure

Question 14

4 types of crystalline solids

Answer 14

all metals
non-glassy ceramics
polymer fibers
tooth enamel

Question 15

a repeated consistent internal structure is known as a

Answer 15

crystalline structure

Question 16

what is stress

Answer 16

forces within the structure that cause strain

Question 17

what is strain

Answer 17

the deformation in the structure

Question 18

what is surface tension

Answer 18

caused by the attractive forces b/w molecules of a liquid.

Question 19

what is a good wetting property?

Answer 19

small contact angle -> promotes capillary penetration

Question 20

2 mechs of adhesion

Answer 20

chemical and mechanical

Question 21

what does adhesion occur through

Answer 21

primary or secondary bonds to the substrate

Question 22

chemical adhesions is used to bond to

Answer 22

dentin

Question 23

many cements bond to

Answer 23

the calcium of hydroxyapatite

Question 24

what is ADsorption

Answer 24

process where a liquid or gas adheres to a SURFACE

Question 25

what is ABsorption

Answer 25

process where a liquid or gas PENETRATES into solid material

Question 26

3 mechanical forces in the jaw

Answer 26

torsion, compression, shear

Question 27

stress is always a combo of

Answer 27

tensile, compressive and shear stresses

Question 28

what is Poisson’s ratio

Answer 28

measure of lateral strain relative to axial strain

Question 29

would you want to use a ductile or brittle material

Answer 29

ductile

Question 30

what is resilience

Answer 30

amount of elastic energy a material can absorb.

area of energy UNDER the linear portion of the stress-strain diagram

Question 31

what is toughness

Answer 31

area under the entire stress-strain curve. represents the amt of energy the material can absorb before failure

Question 32

low VP causes faster/slower evaporation

Answer 32

SLOWER

Question 33

creep

Answer 33

is a slow deformation of a viscoelastic material over time

CREEPS UP

Question 34

stress

Answer 34

force per unit area

Question 35

ultimate strength

Answer 35

max stress the material withstands

Question 36

yield

Answer 36

point at which plastic strain begins

Question 37

plastic strain

Answer 37

permanent deformation

Question 38

shear strain

Answer 38

caused by shear stress