Chapter 3 Physical and Mechanical Properties of Dental Materials

Question 1

Strong bonds with electronic attractions; ionic bonds, covalent bonds, metallic bonds

Answer 1

Primary bonds

Question 2

Weaker bonds than primary bonds; hydrogen bonds, van der Waals forces, London Dispersion forces

Answer 2

Secondary bonds

Question 3

The hardness, and likelihood of breaking or cracking of a material

Answer 3

Brittleness

Question 4

The measure of the weight of a material compared with its volume

Answer 4

Density

Question 5

The resistance of a solid to penetration

Answer 5

Hardness

Question 6

The maximum amount of stress a material can withstand without breaking

Answer 6

Ultimate strength

Question 7

The ability of a material to recover its shape completely after deformation from an applied force

Answer 7

Elasticity

Question 8

A material’s resistance to deformation

Answer 8

Stiffness

Question 9

The greatest stress a structure can withstand without permanent deformation

Answer 9

Proportional Limit

Question 10

The ability of a material to absorb energy without permanent deformation

Answer 10

Resilience

Question 11

The ability of a material to resist fracture

Answer 11

Toughness

Question 12

The ability of an object to be pulled or stretched under tension without rupture

Answer 12

Ductility

Question 13

The ability to be compressed and formed into a thin sheet without rupture

Answer 13

Malleability

Question 14

The strength of a material at fine margins

Answer 14

Edge strength

Question 15

The ability of a material to withstand damage due to pressure or wear

Answer 15

Durability

Question 16

The ability of a liquid material to resist flow

Answer 16

Viscosity

Question 17

Liquids that flow more readily under mechanical force

Answer 17

Thixotropic fluids

Question 18

Restorations placed directly into a cavity preparation

Answer 18

Direct Restorative Materials

Question 19

Materials used to fabricate restorations outside the mouth that are subsequently placed into the mouth

Answer 19

Indirect Restorative Materials

Question 20

Restorations expected to be long-lasting

Answer 20

Permanent Restorations

Question 21

Restorations expected to last several days or weeks

Answer 21

Temporary Restorations

Question 22

Restorations expected to last several weeks to months

Answer 22

Intermediate Restorations

Question 23

The amount of time allotted to bring the components of a material together into a homogenous mixture

Answer 23

Mixing time

Question 24

The time at which the material has reached its ultimate state

Answer 24

Final set time

Question 25

The time permitted to place and manipulate the material in the mouth

Answer 25

Initial set time

Question 26

Materials that set through a time chemical reaction with the combination of a catalyst and base

Answer 26

Chemical set materials

Question 27

Materials that require a blue light source to initiate a reaction

Answer 27

Light activated materials

Question 28

Materials that polymerize when the materials is initiated by exposure to a blue light source then continue with a chemical set reaction

Answer 28

Dual set materials

Question 29

The useful life of a material before it deteriorates or changes quality

Answer 29

Shelf life

Question 30

Primary bond, has density, hardness, elasticity, stiffness, ductility, malleability, brittleness

Answer 30

Solids

Question 31

measure of weight has compared to volume

Answer 31

density

Question 32

resistance of a solid to penetration

Answer 32

hardness

Question 33

ability to deform and return to original shape

Answer 33

elasticity

Question 34

resistance to deformation

Answer 34

stiffness

Question 35

amount of dimensional change it can withstand without breaking

Answer 35

ductility

Question 36

ability to withstand stress and stretching

Answer 36

malleability

Question 37

inability to withstand stress and stretching

Answer 37

brittleness

Question 38

Molecules are not confined to a specific pattern, Viscosity, Thixotropic materials

Answer 38

Liquids