Dental Hygiene Board Review: Dental Materials

Front 1

the chemical attraction between unlike molecules

Back 1

adhesion

Front 2

the chemical attraction between like molecules

Back 2

cohesion

Front 3

an index which indicates how one material reacts to temperature extremes in relation to another

Back 3

Coefficient of thermal expansion

Front 4

the force at which a material breaks under pressure

Back 4

compressive strength

Front 5

slow dimensional change caused by compression

Back 5

creep

Front 6

the ability to undergo change of form without breaking

Back 6

ductitlity

Front 7

a materials ability to recover its initial shape after undergoing a force

Back 7

elasticity

Front 8

an electrical current generated by dissimilar metals in an acidic environment

Back 8

galvanism

Front 9

the process of gelling (solidification by cold)

Back 9

gelation

Front 10

absorption of a solvent by a gel

Back 10

imbition

Front 11

a metails capacity to be shaped by force or pressure

Back 11

malleability

Front 12

passage of oral fluids/bacateria into and out of tooth structure due to marginal gap or failure of marginal (restorative) seal

Back 12

Microleakage (percolation)

Front 13

the linking, branching, or cross linking of samller moleculres

Back 13

polymerization

Front 14

the force at which a material cannot return to tis original shape

Back 14

proportional limit

Front 15

contraction of gel due to the loss of a solvent

Back 15

sneresis

Front 16

the force needed to stretch a material to the point of fracture

Back 16

tensile strength

Front 17

resistance to flow

Back 17

viscosity

Front 18

an alloy of mercury with silver, copper, tin and zinc

Back 18

amalagam

Front 19

silver is a ___ metal susceptible to _____

Back 19

base

corrosion

Front 20

Why is copper added to amalgam

Back 20

to minimise corrosion (gamma II phase eliminated)

Front 21

Desirable features of amalgam

Back 21

-durable

-similar compressive strength to enamel

-relatively inexpensive

Front 22

undesirable features of amalgam

Back 22

-unattractive

-high thermal conductivity

-dimensionally unstable (creep)

-delayed expansion if contaminated by saliva

-requires smooth surface

-fracturable by excessive occlusion

-susceptible to galvanism when new

Front 23

True or false: when polishing amalgam you move from fine to coarse agents to remove surface tarnish, stains, flash, and roughness

Back 23

False: course to fine

Front 24

What can reduce the rate of corrosion (less surface area) in amalgam

Back 24

polishing

Front 25

what do you final polish amalgam with?

Back 25

tin oxide (diamond paste)

Front 26

You should use a light touch with water and short bursts with water to avoid _______ damaging heat

Back 26

odontoblast

Front 27

How do you avoid an overhang when placing an amalgam?

Back 27

-using properly places band and wedges

-detect overhang with explorer

Front 28

Dental resins (BIS-GMA or urethan dimethacrylate) which establish micromechanical retention with enamel and dentin by adaptin to relief areas created by condition with 37% phophoric acid

Back 28

bonding agents

Front 29

what percentage of phosphoric acid do you use with bonding agents (dental resins)

Back 29

37%

Front 30

what are the steps to placing a bonding agent?

Back 30

-15-20 sec etch

-rinse

-dry

-apply

-air-thin

-polymerize

Front 31

application of what increases enamel and dentin surface area?

Back 31

phophoric acid

Front 32

polymerization is typically activated by

Back 32

fiber optic light

Front 33

light activated polymerization allows for ____ working time

Back 33

flexible

Front 34

polymerization initiators are typically ______ or ______

Back 34

benzoyl peroxide

tertiary amine

Front 35

bonding failure of a bonding agent are commonly due to contamination by ___ or ___

Back 35

saliva or oils

Front 36

While placing a binding agent, if at any time contamination occurs you to to

Back 36

re-etch

Front 37

bisphenol a-gluycidyl methacrylate

Back 37

BIS-GMA (bonding agent/dental resin)

Front 38

barrier used to protect the occlusal surfaces of teeth from bacterial assault by sealing anatomically unprotected tooth structure with resin

Back 38

pit and fissure sealants

Front 39

During sealant application you need to re-etch if enamel lacks

Back 39

frosty appearance

Front 40

steps to applying sealants

Back 40

-pumice

-rince

-isolate

-etch

-rinse

-dry

-apply

-remove excess

-polymerize

Front 41

retention of sealants is ____

Back 41

mechanical

Front 42

you can check retention of sealant with _____ after polymerization

Back 42

explorer

Front 43

An esthetic restorative material composed of a bonding agent and tooth colored filler particles of various sizes

Back 43

composite

Front 44

Most common filler particles in composite

Back 44

-silicates

-quartz

-glass

Front 45

What is added to composite for radiopacity

Back 45

barium or stontium

Front 46

10-100 microns

Back 46

macrofill

Front 47

1-10 microns

Back 47

midifill

Front 48

0.1-1 micron

Back 48

minifill

Front 49

0.01-0.1 micron

Back 49

microfill

Front 50

.001 micron

Back 50

nanofill

Front 51

blend of micro and midifill

Back 51

hybrid

Front 52

blend of micro, midi, and nanofill particles

Back 52

nano fillled micro hydbrid

Front 53

popular due to high polishability and ease of handling, but require tooth support.

Back 53

microfils

Front 54

popular due to combined strength and beauty

Back 54

hybrids

Front 55

increase surface area and therefore bond strength

Back 55

nonfills

Front 56

increase polishability

Back 56

nanofills

Front 57

what is used to isolate field and prevent salivary contamination

Back 57

rubber dam

Front 58

Composites that are ______ cured are less porous than _____ cured

Back 58

light cured (unmixed)

self cured (mixed)

Front 59

what do you polish composite with?

Back 59

tin oxide (diamond paste)

Front 60

generally used to seal dentin or medicate the dental pulp (seal/medicate)

Back 60

liners

Front 61

what liner is used to stimulate reparative dentin formation

Back 61

calium hydroxide

Front 62

what liner is used to soothe pulp and is oily

Back 62

zinc-oxide eugenol

Front 63

what liner is used to seal tubules and releases fluoride

Back 63

resin modified glass ionomer

Front 64

generally used to provide thermal insulation or mechanical protection for the dental pulp ( insulate/protect)

Back 64

bases

Front 65

bases include all ____ because they are poor thermal conductors, and have adequate compressive strength

Back 65

cements

Front 66

used to affix a restoration to tooth structure or as a base

Back 66

cements

Front 67

What type of cement has an exothermic reaction on mixing (use a cool glass slab)

Back 67

zinc phosphate cement

Front 68

What cement forms a mechanical interlock between tooth and casting

Back 68

zinc phosphate cement

Front 69

what cement has high chemical affinity for enamel

Back 69

polycarboxylate cement

Front 70

what cement has powder mixed with polyacrylic acid

Back 70

polycarboxylate cement

Front 71

what cement bind with dentin

Back 71

glass ionomer cement

Front 72

what cement releases fluoride

Back 72

glass ionomer cement

Front 73

what are the 6 types of cement

Back 73

-zinc phosphate

-polycarboxylate

-glass ionomer

-resin

-hybrid

-zinc-oxide eugenol

Front 74

what cement has a coefficient of thermal expansion that approximates tooth structure

Back 74

glass ionomer

Front 75

what cement can be used as a class V restorative material

Back 75

glass ionomer

Front 76

what cement is tooth colored to affix estheic restorations like porcelain laminate veneers and tooth colored inlays, onlays, or crowns, and clear orthodontic brackets

Back 76

resin cement

Front 77

what cement is also used for luting etched metal retainers such as resin bonded bridges and prefabricated endodontic posts

Back 77

resin cement

Front 78

which cement is a resin-modified glass ionomer

Back 78

hybrid cement

Front 79

which cement seals dentin effectively to minimize sensitivity (unfilled resin/bonding agent)

Back 79

hybrid cement

Front 80

which cement releases fluoride

Back 80

hybrid and glass ionomer

Front 81

which cement is commonly used for temporary cementation

Back 81

zinc-oxide eugenol

Front 82

zinc oxide eugenol cement can be mixed putty like to cement a _________________

Back 82

temporary aluminum shell crown

Front 83

zinc oxide eugenol cement can be mixed creamy like to cement a _____________

Back 83

custom acrylic temporary crown

Front 84

what is typically used to clean zinc oxide eugenol off of instrument

Back 84

orange oil

Front 85

what are the different types of impression materials

Back 85

rigid

flexible (aqueous or non aqueous)

Front 86

what are the different types of rigid (inelastic) impression materials?

Back 86

-plaster, Type I gypsum

-compound

-zinc oxide eugenol

Front 87

what rigid impression material is used for occlusal records

Back 87

plaster, type I gypsum

Front 88

what type of rigid impression material is used for making a border mold custom tray

Back 88

compound

Front 89

what type of rigid impression material is used to make final impression, full dentures

Back 89

zinc-oxide eugenol

Front 90

water-soluble or hydrophilic

Back 90

aqueous

Front 91

agar is a ____ hydrocolloid

Back 91

reversible

Front 92

a _____ hydrocolloid undergoes a physical change while a _____ hydrocolloid undergoes a chemical reaction

Back 92

reversible

irreversible

Front 93

a ____ hydrocolloid is under a sol-gel state and is temperature dependent

Back 93

reversible

Front 94

solidification by cold (type of change); occurs in a reversible hydrocolloid

Back 94

solidification

Front 95

a ____ hydrocolloid is popular for multiple preparations but is unstable

Back 95

reversible

Front 96

a ____ hydrocolloid is susceptible to imbibition and syneresis

Back 96

reversible and irreversible

Front 97

a ____ hydrocolloid is not temperature dependent

Back 97

irreversible

Front 98

alginate is a ______ hyrdocolloid

Back 98

irreversible

Front 99

setting of an irreversible hydrocolloid can be delayed by _____ water or accelerated by ____ water

Back 99

cold

warm

Front 100

a ____ hydrocolloid is a popular choice or study models' but unstable

Back 100

irreversible hydrocolloid

Front 101

Why do you need to aerate (fluff) alginate (irreversible hydrocolloid)

Back 101

prevents settling/compation of powder

Front 102

water-insoluble or hydrophobic

Back 102

non-aqueous

Front 103

What are the 4 types of non aqueous flexible impression materials

Back 103

-polysulfide rubber

-polyether rubber

-silicone rubber

-vinypolysiloxane

Front 104

What flexible impression material is messy, smelly, and must be poured the same day

Back 104

polysulfide rubber

Front 105

What flexible impression material is relatively rigid and has good detail but is still unstable in the presence of moisture

Back 105

polyether rubber

Front 106

What flexible impression material is putty like and rarely used

Back 106

silicone rubber

Front 107

condensation reaction silicone

Back 107

silicon rubber

Front 108

addition reaction silicone

Back 108

vinylpolysiloxane

Front 109

What flexible impression material is tasteless/odorless, stable, strong, accurate, easily mixed, and capable of multiple pours

Back 109

vinylopolysiloxane

Front 110

mineral, calcium sulfate di-hydrate

Back 110

gypsum products

Front 111

why is gypsum heated

Back 111

to refine the material and drive off some of the water

Front 112

_____ must be added back to gypsum to reconstitute (utilize) the material, which leads to a setting expansion

Back 112

water

Front 113

the more water needed in gypsum, the ____ the setting expansion and the _____ the compressive strength of the final product

Back 113

greater

lower

Front 114

_____ requires more water to reconstitute than _______ and therefore has a _____ compressive strength

Back 114

beta-calcium sulfate hemi hydrate (plaster)
alpa-calcium sulfate hemi hydrate (stone)
lowered

Front 115

another word for demensional change

Back 115

setting expansion

Front 116

____ is superior to _____ as a gypsum material

Back 116

alpa (stone)

beta (plaster)

Front 117

quality of the product (gypsum grade) is determined by _____

Back 117

refinement

Front 118

Plaster, Type II gypsum

Back 118

beta-calcium sulfate hemi hydrate

Front 119

stone, type IIII gypsum

Back 119

alpa calicum sulfate hemi hydrate

Front 120

diestone, typer IV gypsum

Back 120

alpha calcium sulfate hemi hydrate, contains additive to make more durable and wear resistant

Front 121

When choosing a gypsum material, selection is dependent upon _____ and ______ desired

Back 121

strength

dimensional accuracy

Front 122

what gypsum material is used for orthodontic models because

Back 122

plaster

Front 123

what gypsum material is used for study model/working models

Back 123

stone

Front 124

what gypsum material is used for crown and bridge die or model

Back 124

improved stone or diestone

Front 125

what gypsum material is easy to polish

Back 125

plaster

Front 126

what gypsum material is more accurate and wear resistant

Back 126

stone

Front 127

what gypsum material is accurate and MOST wear resistanct

Back 127

diestone

Front 128

you can add ______ to gypsum to accelerate set

Back 128

potassium sulfate

Front 129

you can mix gypsum with ____ water to accelerate set

Back 129

warm

Front 130

you can add _____ to gypsum to slow set

Back 130

borax

Front 131

True or false: water should be measured and gypsum should be weighed to mix

Back 131

true

Front 132

air incorporated into gypsum will result in

Back 132

surface voids

Front 133

the gypsum model base is trimmed _____ to the midline between central incisors

Back 133

perpendicular

Front 134

what material has multiple uses and is comprised primarily of paraffin

Back 134

waxed

Front 135

types of wax material

Back 135

-beeswax

-carnauba

-rosin

-colarants

Front 136

what type of wax is used for caset restorative patterns

Back 136

inlay and casting wax

Front 137

what type of wax is useful in removable prosthetic procedures (dental plate)

Back 137

baseplate wax

Front 138

what type of wax is useful to obtain occlusal records

Back 138

bite registration wax

Front 139

what type of wax is used in pouring models

Back 139

boxing wax

Front 140

what type of wax becomes sticky when heated, used to attach models

Back 140

sicky wax

Front 141

what type of wax is used to modify the shape of impression trays and cushion braces

Back 141

utility wax

Front 142

Used to fabricate inlays, onlays, crowns, and bridges

Back 142

casting alloys

Front 143

properties of casting alloys are determined by

Back 143

components

Front 144

casting alloys are classified as _____ or _____ based on compostition

Back 144

precious or non precious

Front 145

Precious alloys contain ____ metals

Back 145

noble

Front 146

what type of metal resists tarnish and corrosion

Back 146

noble

Front 147

what are the noble metals used in dentistry

Back 147

-gold

-platinum

-palladium

Front 148

nonprecious alloys contain ____ metals

Back 148

base

Front 149

what type of metal is subject to tarnish and corosion

Back 149

base mentals

Front 150

what type of metal may be allergenic (gingival inflammation

Back 150

base metals

Front 151

what are the base metals used in dentistry

Back 151

silver

copper

nickel

tin

zince

Front 152

intra-orally gold may be polish with

Back 152

tin oxide

Front 153

extra-orally gold may be polished with

Back 153

rouge

Front 154

occlusal wear of casting alloys may be caused by opposing _____ resotrations

Back 154

porcelain

Front 155

gold foil

Back 155

small, gold, gum line, anterior
only way

Front 156

biocompatible titanium alloy prosthesis used to replace missing teeth

Back 156

implants

Front 157

implants may be ____ or have a ____ shape

Back 157

cylindrical

blade

Front 158

implants are endosteal meaning

Back 158

within bone

Front 159

what is the leading cause of failure with implants

Back 159

mobility caused by lack of osseotintergraion or inadequate bone

Front 160

what contra indication to implant placement

Back 160

-inadequate bone

-uncontrolled periodontal disease

-smoking

-infection

Front 161

True or false: patients cannot use an electric tooth brush because it will damage the implant

Back 161

false

Front 162

True or false: the hygienist ay use an air polisher without implant damage

Back 162

true

Front 163

active ingredient in consumer products: triclosan

Back 163

antimicrobial agent in gum care toothpaste

Front 164

active ingredient in consumer products: pyrophosphate

Back 164

tarter control toothpaste

Front 165

leading cause of dentinal hypersensitivity (active ingredient)

Back 165

pyrophosphate

Front 166

active ingredients in desensitization toothpastes

Back 166

potassium nitrate

sodium citrate

strontium chloride

Front 167

carbamide peroxide breaks down into _____ and ____

Back 167

hydrogen peroxide and urea