Final Exam Content

Question 1

A mixture of two or more metals

Answer 1

Alloy

Question 2

A reaction that occurs when the silver-based alloy is mixed with mercury

Answer 2

Amalgamation

Question 3

Restorative material composed of silver-based alloy (silver, copper, and tin) mixed with mercury

Answer 3

Dental amalgam

Question 4

Irregularly shaped particles formed by shaving fine particles from an alloy ingot

Answer 4

Lathe-Cut alloy

Question 5

Alloy particles produced as small spheres

Answer 5

Spherical Alloy

Question 6

Mixture of lathe-cut and spherical alloys

Answer 6

Admixed alloy

Question 7

A chamical reaction between tin in the silver-based alloy and mercury that causes corrosion in the amalgam

Answer 7

Gamma-2 Phase

Question 8

Oxidation affecting a thin layer of.a metal at its surface; Not as destructive as corrosion

Answer 8

Tarnish

Question 9

Oxidation from interaction of a metal in the presence of a solution containing electrolytes (such as siliva): a chemical or electrochemical process through which a metal is attacked by natural agents, resulting in partial or complete dissolution, deterioration, or breakdown of the amalgam

Answer 9

Corrosion

Question 10

Mechanical device used to mix the silver-based alloy particles with mercury to produce amalgam

Answer 10

Triturator (Amalgamator)

Question 11

The gradual expansion of a zinc-containing amalgam over a period of weeks to months. Is associated with the development of hydrogen gas, which is caused by the incorporation of moisture in the plastic mass during its manipulation in a cavity preparation

Answer 11

Delayed Expansion

Question 12

The gradual fracture of the perimeter or margin of a dental amalgam filling, which leads to the formation of gaps between the amalgam and the tooth

Answer 12

Marginal breakdown

Question 13

What other materials can be added to dental amalgam to get specific properties?

Answer 13

Small amoutns of other metals like palladium, indium, zinc, or gold

Question 14

The reaction between the alloy and mercury called ____, forms the ____

Answer 14

Amalgamation; dental amalgam material

Question 15

T or F: Dental Amalgam is an alloy

Answer 15

TRUE

Question 16

Who was dental amalgam first used by?

Answer 16

The Chinese

Question 17

When was dental amalgam introduced to the US?

Answer 17

1830s by crawcours

Question 18

What happens with the release of mercury from amalgam restorations?

Answer 18

Due to increased activities or chewing, brushing teeth, and nocturnal bruxism; Hg levels can approach occupational health limits

Question 19

T or F: Dental amalgam requires removal of healthy tooth structure.

Answer 19

TRUE

Question 20

What is the purpose of Silver in dental amalgam?

Answer 20

Increased strength, setting expansion

Reduces setting time, flow, and corrosion

Question 21

What is the purpose of tin in dental amalgam?

Answer 21

helps form tin/silver compounds and is involved in the gamma phase

Increases setting time

Reduces strength, hardness, and setting expansion

Question 22

What is the purpose of mercury in dental amalgam?

Answer 22

To wet the amalgam and increase the rate of reaction

Question 23

What is the purpose of copper in dental amalgam?

Answer 23

Increases mechanical properties and corrosion resistance

Decreases creep and amount of gamma-2 phase formation

Question 24

What is the purpose of zin in dental amalgam?

Answer 24

to grab oxygen

Question 25

Allowy powder that contains powder particles of one composition that requires less condensation force and mercury

Answer 25

Simple composition

Question 26

What is a good example of a spherical high copper amalgam?

Answer 26

Tytin

Question 27

The dental amalgam phase that is the strongest and most corrosion-resistant, making up about 25% of the amalgam

Answer 27

Gamma phase (Ag-Sn)

Question 28

The dental amalgam phase that is moderately strong but brittle, forming roughly 50% and serving as the binding matrix

Answer 28

Gamma 1 phase (Ag-Hg)

Question 29

The dental amalgam phase that is the weakest and most prone to corrosion, comprising about 10% of the amalgam and representing the structure's "weak link"

Answer 29

Gamma 2 phase (Sn-Hg)

Question 30

In high-copper alloys, the gamma 2 phase reacts further with silver-copper particles to form the _____ which significantly reduces the gamma 2 phase which lowers the amalgam's susceptibility to corrosion

Answer 30

The eta phase

Question 31

If there is more mercury than required, then the resultant mix will be ___

Answer 31

weaker

Question 32

If there is less mercury than required then...

Answer 32

the alloy particles might not be sufficiently wet

Question 33

T or F: Lathe-cut amalgam alloys require more mercury to be wet than the spherical alloy

Answer 33

True

Question 34

What was the first high copper amalgam called?

Answer 34

Dispersally

Question 35

The gradual expansion of zinc-containing amalgam over a period of weeks to months associated with hydrogen gas

Answer 35

Delayed expansion

Question 36

Why is corrosion an advantage?

Answer 36

Helps to produce a good marginal seal

Question 37

Formation of an oxidation cell in the marginal gap that causes a rapid deterioration in the properties of amalgam

Answer 37

Crevice corrosion

Question 38

The corrosion process is associated especially with what phase?

Answer 38

Gamma-2 phase

Question 39

Which phase is more electronegative?

Answer 39

Gamma-2 phase

Question 40

A surface phenomenon that causes discoloration of dental restorations due to chemical reactions between amalgam and the oral environment

Answer 40

Tarnish

Question 41

A chemical or electrochemical process where natural agents attack the metal, leading to partial or complete dissolution and deterioration

Answer 41

Corrosion

Question 42

Caused by using two different metals in the mouth, such as amalgam next to a gold alloy, due to saliva acting as an ion conductor

Answer 42

Galvanic cell

Question 43

The by-products of the corrosion process in the material can migrate into the dentinal tubules causing discoloration

Answer 43

Enamel discoloration (Amalgam Blue)

Question 44

Some fine particles of the amalgam material can migrate into the soft tissues creating a benign lesion

Answer 44

Amalgam tattoo

Question 45

Produces a hot, sticky mix with decreased working and setting time and slightly increased setting contracton

Answer 45

Overtrituration

Question 46

Produces a grainy, crumbly mix, which cannot be used; increases creep and has a low tensile and compressive strength

Answer 46

Undertrituration

Question 47

Waxes of various heat-sensitive substances, consisting of hydrocarbons or esters of fatty acids that are insoluble in nonpolar organic solvents (water)

Answer 47

Natural Wax

Question 48

A complex of organic compund of varied chemical compositions. Solid plastic or pliable substance originated from petroleum products

Answer 48

Synthetic wax

Question 49

Waxes are composed of a blend of...

Answer 49

Medium to high molecular weight polymers of the alkane series with esters and alcohols

Question 50

Examples of Plant-based waxes

Answer 50

Carnauba - palm tree Ouricury - Plant

Question 51

Examples of animal-based waxes

Answer 51

Beeswax - beehive Spermacetti - Whale

Question 52

The unit of measurement of an object or substance's resistance to being deformed elastically when stress is applied to it

Answer 52

Elastic modulus

Question 53

The maximum stress a material can withstand before it begins to experience plastic deformation meaning it will not return to its original shape after the load is removed

Answer 53

Proportional limit

Question 54

The capacity of a material or structure to withstand loads tends to reduce size (compression).

Answer 54

Compressive strength

Question 55

The capacity for a material to withstan loads of tending to elongate, resisting tension (being pulled apart)

Answer 55

Tensile Strength

Question 56

Slippage of molecules over each other, dependent on temperature; increases as the melting point is approached

Answer 56

Flow

Question 57

Stresses that remain in a solid material after the original cause of the stresses has been removed. Shape "memory"

Answer 57

Residual stress

Question 58

The ability of a material to sustain significant plastic deformation before fracture; increases as temperature is increased

Answer 58

Ductility

Question 59

Overheating wax will evaporate or burn off the low molecular weight components making the wax...

Answer 59

brittle

Question 60

Coefficient of thermal expansion =

Answer 60

degree of expansion/change in temperature

Question 61

Waxes display plastic deformation under pressure which depends on the...

Answer 61

temp, pressure, and duration

Question 62

High CTE + high thermal resistance =

Answer 62

temp gradients and residual stresses in wax patterns

Question 63

Waxes return to their original shape after manipulation

Answer 63

Elastic memory

Question 64

A mixture of two or more waxes with other additives used in dentistry for casts, construction of nonmetallic denture bases, registering jaw relations, and other laboratory work

Answer 64

Dental Wax

Question 65

What are the 3 types of dental wax?

Answer 65

Pattern wax, processing wax, and impression wax

Question 66

Forms the general predetermined size and contour of an artificial dental restoration, which is to be constructed of a more durable material such as gold or acrylic resins

Answer 66

Pattern wax

Question 67

Used to establish vertical dimension and plane of occlusion, and is the initial arch form for dentures

Answer 67

Base plate (Pattern wax)

Question 68

Use for the metallic framework of restorative partial dentures

Answer 68

Casting wax (Pattern wax)

Question 69

Pattern material to accurately represent desired mold space for inlays, onlays, and crowns

Answer 69

Inlay wax

Question 70

What is the major component of inlay wax?

Answer 70

60% Paraffin wax 25% Carnuba wax

Question 71

How are indirect patterns made?

Answer 71

On a gypsum die (Type 4 or 5) at room temp

Question 72

What is the major component of base plate wax?

Answer 72

80% paraffin 12% beeswax

Question 73

Used in a dental lab during the processing of indirect dental resorations. No ADA specification. Boxing, utility, or sticky wax

Answer 73

Processing wax

Question 74

Contouring a standard perforated tray for an impression, on lingual portion of a bridge pontic while a plaster splint is poured

Answer 74

Utility wax

Question 75

A mixture of waxes and resins that adheres closely to surfaces. This wax fractures rather than flows if it is deformed during soldering or repairs.

Answer 75

Sticky wax

Question 76

Waxes that are specialty and used for specific purposes

Answer 76

Impression wax

Question 77

Type I impression compound

Answer 77

Low fusing (green stick) and medium fusing (impression)

Question 78

Type II impression compund

Answer 78

high fusing (tray)

Question 79

What is the main component of impression compound wax?

Answer 79

30% rosin 30% copal resin 25% Talc

Question 80

What is the main use for impression compounds?

Answer 80

Border molding (dentures)

Question 81

T or F: Waxes has a high CTE

Answer 81

True

Question 82

The pH where saliva and plaque are no longer saturated with calcium and phosphate, allowing hydroxyapatite in enamel to disolve

Answer 82

Critical pH

Question 83

Newly erupted tooth =

Answer 83

Carbonate apatite = highly soluble

Question 84

Matured tooth =

Answer 84

Hydroxyapatite = less soluble (pH 5.5)

Question 85

Mature tooth with fluoride =

Answer 85

Fluorapatite = least soluble (pH 4.5)

Question 86

Which Fluoride is used for a post-eruptive effect, inhibits demineralization and supports remineralization, and is antibacterial?

Answer 86

Topical fluoride

Question 87

Which fluoride has a developmental effect, reduces acid solubility or enamel, and improves tooth morphology by promoting shallow fissures of decreased diameter?

Answer 87

Systemic fluoride

Question 88

This is a result of excess fluoride presenting as dull white-yellow spots to mottled, brown enamel that poses no risk after the age of 8 EXCEPT to the third molars?

Answer 88

Fluorosis

Question 89

What stage of tooth development does fluorosis affect?

Answer 89

Mineralization phase

Question 90

What is the primary source of systemic fluoride?

Answer 90

Fluoridated drinking water

Question 91

How much fluoride is in drinking water?

Answer 91

0.7mg/L; max 2mg/L

Question 92

Reverse osmosis and distillation filters result in...

Answer 92

removal of fluoride

Question 93

Carbon-charcoal filters result in...

Answer 93

A minimal effect on fluoride

Question 94

What are the primary sources of topical fluoride?

Answer 94

Toothpaste, rinses, foams, and gels

Question 95

Toothpaste that contains 1000ppm, begins with the eruption of the first primary tooth and is safe for a child to swallow up to 0.3mg/day

Answer 95

Over-the-counter toothpaste

Question 96

Toothpaste that contains 5000ppm and is only for teens/adults due to a swallowing risk.

Answer 96

Prescription toothpaste

Question 97

A source of topical fluoride that contains 2200ppm OTC or 22,000ppm prescription which is acceptable for use after age 6

Answer 97

Rinses

Question 98

Risks and benefits of Sodium Fluoride (NaF)

Answer 98

Benefit: Not harmful to resin Risk: Neutral pH = slower rate of absorption into enamel

Question 99

Risks and benefits of Acidulated Phosphate Fluoride

Answer 99

B: Acid may etch resin R: Low pH (3.5) = faster rate of F delivery into the enamel

Question 100

Risks and benefits of Stannous Fluoride

Answer 100

B: Reduces plaque retentinon and monitor complience R: stains teeth

Question 101

The use of scientific evidence validated by peer review and repeat studies to inform clinical decisions

Answer 101

Evidence-based dentistry

Question 102

The gold standard of evidence-based healthcare which analyze all research on a topic and summarize evidence, minimize bias, and inform healthcare decisions

Answer 102

Cochrane review

Question 103

The most common chronic disease of childhood

Answer 103

Dental caries

Question 104

How long does it take for plaque to form on teeth?

Answer 104

20 min

Question 105

What is the critical pH for the breakdown of enamel?

Answer 105

pH = 5.5

Question 106

80-90% of caries in permanent teeth and 44% of caries in primary teeth occur where?

Answer 106

in pits and fissures

Question 107

Coating placed on the hard-to-clean grooves of teeth to prevent tooth decay

Answer 107

Sealants

Question 108

Where are sealants most often placed?

Answer 108

Molars

Question 109

Are sealants placed on premolars?

Answer 109

Yes; especially Asian and Hispanic populations due to dens andante

Question 110

Are sealants placed on incisors?

Answer 110

Yes; especially in Hispanic populations with a pronounced lingual fossa

Question 111

Prevention of disease from initiating

Answer 111

Primary prevention

Question 112

Prevention of disease progression and recurrence

Answer 112

Secondary prevention

Question 113

Prevention of loss of function

Answer 113

Tertiary prevention

Question 114

Sealants being used in school-based public health programs are a form of...

Answer 114

primary prevention

Question 115

Sealants inhibiting the progression of a noncavitates carious lesion is a form of...

Answer 115

secondary prevention

Question 116

What is the composition of resin sealants with its benefits and downsides

Answer 116

C: resin matrix w. fillers and photoinitiator B: Durability and strength D: Technique sensitive

Question 117

What is the composition of glass ionomer sealants with its benefits and downsides

Answer 117

C: Acid + Base fluoride-containing B: Fluoride-releasing D: Moisture contamination is okay, lower durability

Question 118

T or F: Sealants are more effective in reducing put and fissure cavities than fluoride

Answer 118

True

Question 119

What are the most common injured teeth?

Answer 119

Maxillary incisors

Question 120

What increases the risk of dental trauma?

Answer 120

Class II malocclusion, lip incompetence, bullying, ADHD

Question 121

A form of protection that covers maxillary teeth EXCEPT for class III occlusion (underbite) and is required by the NCAA in field hockey, football, ice hockey, and women and men's lacrosse

Answer 121

Mouthguards