Exam II-Impression,amalgam,g.i.,etc

Question 1

Lets get it shorty: What are the 4 advantages to GLASS IONOMERS?

Answer 1

1.Chemical adhesion to tooth 2.Flouride Release 3. CTE similar to tooth 4.Biocompatable

Question 2

What is an RMGI and what are the two ways it is cured?

Answer 2

Resin-modified glass ionomer…1.acid/base reaction 2.light/chemical cure

Question 3

What are the three phases in the CONVENTIONAL setting reaction for a Glass Ionomer?

Answer 3

1.Ion-Leaching Phase 2.Hydrogel 3.Polysalt-Gel Phase

Question 4

What is the MOST important part of the Ion-leaching phase in conventional G.I. setting? What are two nuggets of info about this step?

Answer 4

Formation of NaF!…1.Its not native to the Matrix 2.Its physical properties are not affected by depletion

Question 5

What are the two steps to the setting reaction of RMGI?

Answer 5

1.Acid-base rxn: proceeds slowly 2.Free radical polymerization (light/chemical initiated)

Question 6

What is the method of Fluoride release in Glass Ionomers? How long for the first stage?

Answer 6

1.Rapid early release from matrix: 1-2 days 2.Slow long term release from particle

Question 7

Fluoride release does not result in loss of _________ from the glass ionomer because it does not take part in the ______ formation.

Answer 7

physical properties…matrix

Question 8

Which one releases more fluoride: conventional or RMGI?

Answer 8

HAHA gotcha! they are similar…

Question 9

G.I. can act as a fluoride _______ by the uptake and _______ of topical fluorides.

Answer 9

reservoir…re-release

Question 10

What are the 2 contraindications for LUTING cements (RMGI’s for CRWN&BRDGE!)?

Answer 10

1.Non-reinforced (can expand) 2.can CRACK all ceramic crowns

Question 11

What are the two types of Elastic impression material?

Answer 11

1.Aqueous Hydrocolloids and 2.Non-Aqueous Elastomers

Question 12

What are the two types of Aqueous Hydrocolloids? Are they reversible??

Answer 12

1.Agar (reversible) 2.Alginate (irreversible)

Question 13

What is the “squeezing” or exuding of H20 from fibril cross linking as it contracts with time?

Answer 13

SYNERESIS

Question 14

What are the three types of non-aqueous impression materials?

Answer 14

1.polysulfide 2.Silicones 3.Polyether

Question 15

What type of impression material is VPS? (4 categories of the tree)

Answer 15

1.Elastic 2.Non-aqueous 3.Silicone 4.Addition

Question 16

Which impression material was noted for only having a single pour? Which impression material was noted for having multiple pours?

Answer 16

Single Pour-Irreversible Hydrocolloid (alginate) Multiple-Addition Silicones (VPS)

Question 17

What is the most RIDGID of all impression materials? It is therefore difficult to remove from areas of _________.

Answer 17

Polyether….UNDERCUTS!

Question 18

Imbibition of an impression material is swelling due to ________.

Answer 18

water absorption

Question 19

What impression material has the longest working time? Shortest?

Answer 19

Agar=longest….Alginate=shortest

Question 20

What is the LEAST rigid of all the impression materials?

Answer 20

polysulfide=hydrocolloids

Question 21

Why do we use AMALGAM?? 1.cost: is is _______ 2.Ease of _____ 3.Proven track record of more then ____ years. 4.Familiarity 5.It is _____-free therefore is has less allergies then composite.

Answer 21

1.inexpensive….2.easy to USE 3.100 years 5.RESIN

Question 22

Which two materials have the best Fluoride recharge? Which material has the worst?

Answer 22

G.I. & RMGI have the best…Compomers have the worst

Question 23

FUNCTION of COPPER in our alloy: it ties up _____, which reduces _______ formation, it reduces ______ which therefore reduces _______ deterioration.

Answer 23

TIN…Gamma-2 formation…reduces CREEP….marginal

Question 24

ZINC in amalgam: it’s used in the _________ process, it decreases _______ of other elements by being the sacrificial _______.

Answer 24

manufacturing….OXIDATION…ANODE

Question 25

The basic composition of amalgam: it is a ______-______ MATIRX containing FILLER particles of ______-______.

Answer 25

Silver-Mercury matrix.....Silver-Tin filler

Question 26

In our brick wall analogy: the filler is the _______ (what two metals again!?) and the matrix is the ______(what two metals again?!)

Answer 26

filler-bricks (silver-tin).....matrix-cement (silver-mercury)

Question 27

What is the formula for the silver-tin filler and what is another NAME for it?? What are the three possible SHAPES for the filler??

Answer 27

Ag3Sn.... GAMMA...numero 1.irregular (LATHE-cut) 2.Spherical 3.Combo

Question 28

What is the formula and another name for our silver-mercury matrix cement?

Answer 28

Ag2Hg3...GAMMA 1

Question 29

What is the formula and name for the VOIDS in our silver-mercury matrix cement?

Answer 29

Sn8Hg....GAMMA 2

Question 30

What is the composition of Single Composition High-Copper Alloys? What two elements then dissolve in mercury?

Answer 30

A Gamma sphere (Ag3Sn) with Epsilon coating (Cu3Sn)...Ag and Sn dissolve in mercury

Question 31

What are the 4 methods of adding Copper to amalgam?

Answer 31

1.(SCS) Single Composition Spherical 2.(ALE)-Admixture: Lathe-cut + spherical Eutectic 3.(ALSCS) Admixture: Lathe-cut + Single Composition Spherical 4.(SCL)-Single Composition Lathe-cut

Question 32

In Single Composition Spherical (SCS)-you use _____ condensation force and a ______ condenser.

Answer 32

LESS force....LARGER condenser

Question 33

Amalgam Material-Related Variables--Dimensional Change: Most high-copper amalgams under go a net _______ which leaves a marginal ____ so there is initial _____ and post-op _______. How is this reduced over time?

Answer 33

CONTRACTION...GAP..leakage...sensativity...reduced with CORROSION over time

Question 34

Amalgam-Dimensional change: What are the 3 factors leading to Net contraction?

Answer 34

1.Type of alloy 2. Condensation technique 3.Trituration Time

Question 35

Amalgam-dimensional change: What type of alloy has more contraction? is this due to more or less mercury?

Answer 35

Sperical Alloys have more contraction..less mercury

Question 36

In amalgam grater condensation technique= _______ contaction.

Answer 36

HIGHER contraction

Question 37

In amalgam overtrituration causes ______ contraction.

Answer 37

HIGHER contraction

Question 38

Amalgam has higher ______ strength VS _____ strength.

Answer 38

Higher compressive strength vs tensile strength

Question 39

Corrosion of amalgam: ______ strength, but _____ margins. Which type of amalgam will corrode faster: low copper or high copper?

Answer 39

reduces strength, but SEALS margins..low copper amalgam corrodes faster

Question 40

______: is slow deformation of amalgam placed under constant load.

Answer 40

CREEP

Question 41

Creep correlates with marginal ________.

Answer 41

breakdown

Question 42

_____ copper amalgams have creep resistance and to PREVENT this Gamma 2 phase you need more than ____% Copper.

Answer 42

HIGH...more than 12% copper

Question 43

What is Trituration?

Answer 43

Mixing of liquid mercury with and alloy powder

Question 44

Overtrituration: will make a "___" mix that _____ to the capsule. It also _____ working/setting time and there is a slight ______ in setting contraction.

Answer 44

"hot" mix that sticks to the capsule...decreases.....increase

Question 45

Undertrituration will cause a _____, _____ mix.

Answer 45

Grainy, crumbly

Question 46

What adapts amalgam to the cavity walls?

Answer 46

Condensation

Question 47

Condensation of amalgam reduces the residual ______ in the restoration.

Answer 47

Mercury

Question 48

After this man, ______, dentists started to "specialize" in removing amalgam to treat purported _______ toxicity.

Answer 48

Hal Huggins...mercury

Question 49

What are the three diseases that removing amalgam purportedly cures?

Answer 49

Leukemia, Hodgkin's Lymphoma, and Multiple Sclerosis

Question 50

Lay population unfamiliar with peer-reviewed dental literature rely on ______ stories and ______.

Answer 50

media stories and the internet

Question 51

About how many amalgam restorations are done per year? Leading to about how many TONS of mercury?

Answer 51

1/2 BBAAABAAABAAABillion....75 tons of Hg

Question 52

What are the two everyday activities that can lead to Mercury vapor being release?

Answer 52

Brushing and Chewing

Question 53

A study showed that it is difficult to determine mercury ______ levels accurately.

Answer 53

vapor

Question 54

What is the average daily dose of mercury of a patient with 8-10 amalgam surfaces? How does this compare to threshold levels?

Answer 54

1-2 micrograms/day avg....1% of the threshold 50 micrograms

Question 55

What are the three forms of mercury? Rank them from least toxic to most...

Answer 55

1.Elemental 2.Inorganic 3.Organic(methyl)

Question 56

What is the only way Mercury can be absorbed in the body?

Answer 56

LUNGS! only 0.1% from G.I. and Skin

Question 57

What accounts for most occupational and home mercury exposures?

Answer 57

Mercury VAPOR

Question 58

What is the MOST TOXIC form of Mercury and is responsible for several mass poisonings???

Answer 58

Organic: Alkyl--> METHYL mercury

Question 59

How do you check for CHRONIC mercury exposure? How do you check for acute exposure?

Answer 59

Chronic: 300+ micrograms/L in URINE...Acute: 6+ micrograms/L in BLOOD

Question 60

How does testing mercury levels in hair compare in accuracy?

Answer 60

Hair is NOT a reliable method for determining mercury exposure

Question 61

Studies found no relationship between amalgam restorations and _________.

Answer 61

Multiple Sclerosis

Question 62

Controlled human studies fail to find link between amalgam or mercury levels and ________.

Answer 62

Alzheimer’s

Question 63

Studies showing no _______ dysfunction due to amalgam restorations

Answer 63

renal

Question 64

Properties of Cements: ____ thickness of a cement has a profound effect on the adaptation of the restoration to the tooth AS WELL AS changing the ___:___ ratio!

Answer 64

Film... POWDER:LIQUID ratio!

Question 65

Ultimate film thickness depends on: _________ of the powder in the liquid...._______ of the liquid.....________ of the cement......Amount of ______ applied at cementation 

Answer 65

Concentration....Viscosity....Consistency....force

Question 66

What are the 2 factors that influence the ease with which cement is expressed from under the restoration?

Answer 66

1.Consistency of the cement and 2. the type of restoration