Dental Materials Test #1 (Paige's)

Front 1

What are 3 reasons for studying dental materials?

Back 1

-How to work with them properly

-Educate pt

-understand behavior of materials

Front 2

Name 5 oral tissues

Back 2

Gingiva, enamel, pulp, periodontium, dentin

Front 3

name five restrictions on dental materials because of the nature of the enviroment

Back 3

temperature, biting forces, corrosion of materials, esthetics, biocompatibility

Front 4

name five dental materials used before 1700

Back 4

gold, ivory, porcelain, wax, zinc oxide

Front 5

name two products developed in the 1800s

Back 5

amalgum, porcelain

Front 6

name three products developed in the 20th century

Back 6

composite, polymers, cast metals

Front 7

name three organizations that create standards for dental materials

Back 7

ADA, CE, ISO, EDA

Front 8

Name five types of restorations

Back 8

crowns, dentures, fillings, bridges, implants

Front 9

name five types of materials used in dentistry

Back 9

impression materials, cements, temporary materials, preventative materials, polishing materials

Front 10

name two types of classification by location of fabrication

Back 10

dirrect/indirect restorative materials

Front 11

Name 5 classifications of dental carries and restoration by location

Back 11

1. Occlusal

2. interprox. post.

3. interprox. ant.

4. Insical angle ant.

5. gingival third

6. incisal angle post

Front 12

Name three phases of atomic bonding

Back 12

Gasses, Liquids, Solids

Front 13

Name three types of primary bonds

Back 13

Ionic, covalent, metalic

Front 14

Name three types of seconday bonds

Back 14

Perminent dipoles, Hydrogen bonds, fluctuating dipoles

Front 15

name five types of dental materials and thier atomic bonds

Back 15

-cermics- ionic

-Metals-electron cloud

-plastic -covalent

-composite

-colloids

Front 16

pure gold is how many carats?

Back 16

24

Front 17

What are four properties of materials?

Back 17

Pysical, mechanical, chemical, biological

Front 18

Density:

Back 18

the mass of a material in a given volume

Front 19

Vapor pressure

Back 19

the measure of a liquids tendeny to become a gas

Front 20

Heat of fusion

Back 20

amount of energy required to melt a material

Front 21

Heat of vaporization

Back 21

amount of energy required to boil a material

Front 22

coefficient of thermal expansion

Back 22

a measure of the change in volume or length in relation tothe change in temp.

Front 23

Eletrical conductivity

Back 23

electricity flowing from one metal to another

Front 24

viscosity

Back 24

"stickiness" materials ability to flow. a low contact angle indicates good wetting

Front 25

Hardness

Back 25

Indicates a materials ability to resist scratching and indentation

Front 26

solubility

Back 26

the ability of a liquid to dissolve in a liquid

Front 27

water sorption

Back 27

the ability of a liquid to absorb water

Front 28

3 parts of color

Back 28

Hue: fundamental color

Chroma: strength or saturation

value: light or darkness of a color

Front 29

interactions with x rays

Back 29

ceramics are radiolucent,

metals are radiopaque

Front 30

Elasticity

Back 30

stretching of atomic bonds

Front 31

strain

Back 31

the change in lenght divided by the original lenght

Front 32

stress

Back 32

the force (load) divided by the cross sectional area of an object.

Stress = load/area

Front 33

Modulus of elasticity

Back 33

stiffness of a material

Front 34

Elastic limit

Back 34

the poit at which permenant deformation begins (yield point)

Front 35

Resilience

Back 35

the ability to absorb energy and not be deformed

Front 36

toughness

Back 36

the energy absorbed up to the failure point of hte stress/strain diagram

Front 37

fracture toughness

Back 37

the measure of the energy required to fracture a material when a crack is present

Front 38

fatigue

Back 38

failure of a material after being stressed repetatively for a long time

Front 39

stress concentration

Back 39

stress increases around defects

Front 40

name and define four types of stress

Back 40

compression - pushing or crushing

tension-pulling

shear-sliding

torsion-twisting

Front 41

Name and define two time dependent properties

Back 41

creep-a small change in shape when an object is under continuous compression

Stress relaxation: a slow decrease in force overtime

Front 42

What are three advantages of using adhesion bonding in dentistry

Back 42

retension restoration,

reduce microleakage

reduction of recurrent carries

Front 43

Who developed the idea of pit and fissure sealants in the 1950s?

Back 43

Dr. Michael Buonocore

Front 44

who developed polycarboxylate cements in the 1970s?

Back 44

Dennis Smith in London

Front 45

when were composite resins developed?

Back 45

1960's

Front 46

what is the difference between adhesive failure and cohesive failure

Back 46

AF: Breaks at the interface of tooth and restoration

CF: Breaks inside bonding material

Front 47

What is the most common acid used to etch teeth?

Back 47

phosphoric acid 37%

Front 48

How many seconds is 37% orthophosphoric acid used to etch?

Back 48

15-30

Front 49

why do deciduous teeth take longer to etch?

Back 49

irregular enamel rods

Front 50

smear layer

Back 50

debre from a high speed burr

Front 51

the "primer" is used as a..

Back 51

wetting agent

Front 52

What are the steps in the "three step" bonding system?

Back 52

etch, prime, bond

Front 53

in the "two step" bonding system the adhesive contains what two things?

Back 53

primer, and adhesive

Front 54

the adhesive mechanism of dental bonding is

Back 54

micromechanical as resin tags

Front 55

glass ionomer cement is composed of what two things?

Back 55

polyacrillic acid

glass particles

Front 56

why does glass ionomer cement bond to teeth?

Back 56

the acid group reacts with the tooth structure and the glass. so they are chemically bonded together

Front 57

What is the functional group in addition polymerization of acrylic resins?

Back 57

-Monomers that have a reactive group

Functional group

C=C bond

Front 58

what is a free radical

Back 58

unpaired electron

Front 59

what are the three steps in additional polymerization

Back 59

initiation, propigation, termination

Front 60

name four ways addition polymerization can be activated

Back 60

Heat, Chemically, light, dual cured

Front 61

name three probs with unfilled resins

Back 61

polymerization shrinkage

coeficient of thermal expansion

strength and abrasion resistance

Front 62

who added fillers "glass particles" to dental resins to form the first composites

Back 62

Dr. raphael bowen

Front 63

in dental composites, what bonds filler to polymer

Back 63

silane

Front 64

what are three components of dental composites

Back 64

matrix, fillers, silane coupling agents

Front 65

name three types of composites according to size of filler

Back 65

Microfilled, Macrofilled, hybrid

Front 66

what is the filler size of Macro composites

Back 66

10-25 um

Front 67

what is the filler size of microfilled composites

Back 67

.03-.05 um

Front 68

what is the filler by weight to Hybrid composites

Back 68

75-80%

Front 69

which types of composite are used for areas needing strength

Back 69

hybrid

Front 70

which type of composite can be polished tobecome very smooth

Back 70

microfilled

Front 71

a special use comp. that has low viscosity

Back 71

flowable

Front 72

why are composites placed incrementally

Back 72

to decrease shrinkage, adequate light cure

Front 73

what is the air inhibition layer

Back 73

polymerization inhibited by oxygen

Front 74

what is the purpose of pit and fissure sealents

Back 74

to reduce carries

Front 75

what types of restoration is a conservative approach to pit and fissure decay

Back 75

preventative resin restoration

Front 76

what is the lutting material of choice for ceramic restorations?

Back 76

composite cements

Front 77

the material of choice for class 5 restoration

Back 77

chemical/ cure glass ionomer products

Front 78

the most popular base/liner?

Back 78

resin modified glass ionomers

Front 79

a combo of glass ionomer and composite material is called

Back 79

compomers

Front 80

what is a dental amalgam?

Back 80

an alloy with murcury. the powdered metal is predominately silver

Front 81

name two kinds of amalgam alloy

Back 81

Lathe cut: from grinding an ingot

sperical cut: from spraying molten metal into an inert atmosphere

Front 82

When was amalgam initially developed?

Back 82

France 1800s

Front 83

what is the composition of low copper amalgam?

Back 83

65% silver

25% tin

1%zinc

less than 6% copper

Front 84

what is the function of silver, tin, copper, and zinc in amalgam?

Back 84

silver: causes setting expansion,increases strength and corrosion resistance'

Tin: causes setting contraction, corrosion resistance

copper: functions much same as silver

Zinc: reduces oxidation

Front 85

What is the weakest and most corrosion prone phase of low copper?

Back 85

Sn-Hg (tin-murcury) the gamma two phase

Front 86

what % copper is in high copper amalgams?

Back 86

10-30% copper

Front 87

what two factors affect the handling and performance of amalgam?

Back 87

manifacturing

Dentist

Front 88

amalgam has high............. strenght,

but low............... strenght

Back 88

compressive, shear

Front 89

what is creep?

Back 89

slow change in shape caused by compression

Front 90

dental amalgam is not recommended for what class restoration?

Back 90

class IV

Front 91

why can zinc cause an amalgam to expand

Back 91

zinc reacts w/ water to produce hydrogen gas which causes the amalagam to expand

Front 92

what percent of patients have mercury toxicity?

Back 92

1% of patients

Front 93

gold foil restorations are limited to what class restoration

Back 93

five