Dental Materials Final Exam
This is just a different format of the powerpoint file that's supposed to get you an A on the final.
Terms in this set (81)
under certain circumstances
Silver amalgam should be used __________________________.
fatigue (NOT compressive failure or dissidence)
Dental restorative materials fail by __________________________.
______________ is predictive of performance.
it should be subjected to clinical trials
In order to gain ADA acceptance for a new type of dental material, __________________________.
strong and will provide excellent service if done well
Gold as a restorative material is _________________________.
polymerization shrinkage of composite
Contraction gaps occur due to ________________________.
__________ does NOT cause chemical erosion.
__________ has the highest coefficient of expansion.
__________________________ is soluble in oral fluids, but releases a ton of fluoride when it dissolves.
The process of percolation is beneficial for _______________.
Which casting material has the poorest dimensional stability?
formation of corrosive products
A decrease in marginal leakage of amalgam is due to __________________________.
______________ is the material with a compressive strength closest to teeth.
Order of thermal coefficient of expansion, from highest to lowest.
Greatest stress to return
What is the elastic limit?
What is ductility?
How much shrinkage is acceptable?
What does Young's Modulus describe?
_______________ is generation of electric currents in the mouth due to the presence of dissimilar metals.
Mercury is ________ of amalgam.
Innes and Youdelis
High copper amalgams were introduced by __________________.
Threshold Limit Value
TLV = __________________________
Self-sealing capability (NOT compressive strength)
____________________ is the major advantage of amalgam.
Have to remove tooth structure
Disadvantage of amalgam
Which diseases have a proven link to amalgam?
slightly elevated and back to normal in 7-8 days
When multiple amalgams are placed in one visit, blood mercury levels will be __________________________.
What is the approximate number of restorations before toxicity according to Meckland and Bergman?
Elimination of the most corrosion susceptible phase
Why is the addition of copper to amalgam an improvement?
All of the above (...that's helpful)
Fewer amalgam restorations are done today than in 1965
_____________ is the strongest and least corrosive amalgam phase.
______________ is the weakest and most corrosive amalgam phase.
The cross-sectional thickness of irreversible hydrocolloid is ___________.
Elastomeric materials (PVS) are best at ______ mm.
Alginate impressions should be poured within ________________.
Let gypsum casts with alginate impressions set _________________.
Type I gypsum is _____________________.
The primary constituent of an alginate impression is ___________________.
The primary constituent of alginate is __________________.
Impression plaster (Type I)
Which type of gypsum is best for mounting casts in an articulator?
Densite (Type IV)
Which material has the best abrasion resistance?
Densite (Type IV)
Which material has the least amount of gauging water?
Which type of gypsum material is used for fabrication of dies?
Relative humidity is a factor in ________________.
What material is helpful for making gold or metal restorations?
gypsum bonded investments
Type III gold are fabricated with _________________.
PO4 (phosphate bonded investments)
PFM crowns are fabricated using ______________________.
Removable partial dentures are fabricated using ____________________ investments.
The primary type of expansion in casting investments is ___________________.
Used as refractories in casting investments (3)
Change from alpha to beta state of crystalline structure
What is inversion?
Who invented the "lost wax process"?
porcelain bonding alloys
Phosphate vs. gypsum
calcium sulfate hemihydrate
What binder is used with the investment for type III gold?
centrifugal force ('tis apparent Donovan doesn't like physics, doesn't know this doesn't exist)
What is used to make gold alloy?
25 microns or less
According to ADA specs #19, casting should record ____________________.
Ethyl alcohol (pour up within 30 min)
Byproduct of condensation silicone
Byproduct of PVS reaction
PVS (addition reaction silicone)
Which of the following has the best elastic recovery?
PVS (addition reaction silicone)
Which impression material has the best fine detail reproduction?
Which impression material has the best dimensional stability?
Irreversible hydrocolloid should be poured within ________ minutes.
____________ is the impression material inhibited by sulfate.
1-2 mm bulk
4-6 mm bulk
Elastomeric cross-sectional thickness = _____________
Water based cross-sectional thickness = _____________
Type IV gold is used to fabricate _______________
NOT silver or chromium
Name 3 noble metals
What is the component of base metal alloys that reduces oxide formation but can cause respiratory issues?
What is the minimal cross-sectional thickness required for high gold?
Casting shrinkage for base metal alloys is ________%.
_______% of women are allergic to nickel.
they are strong
Low gold alloys are the choice for bridges because ___________________.
What is the most important bond in porcelain bonding to metal?
The oxide layer should be _________ in porcelain bonding to metal.
_______________ hold the patent for PFM crowns.
Implants are made from ___________.
95% after 5 years
Best light transmission through core material
single unit crowns
Zirconia is indicated for _____________.
Optimum crown material in terms of wearing permanent dentition, limited tooth removal, and survival.
Which ceramic material undergoes transformation toughening?
Failure rate of all-ceramic crowns is highest in __________.
What is the gold standard for cement?