Question 1

Which of the following statements is(are)true of sprues?

Accepted Answer

A)  Sprues may be made of wax, plastic, or metal. 
B)  Sprues are placed on cusps of the wax pattern. 
C)  Sprues are placed in the central groove of the wax pattern. 
D)  A and B are true statements. 
E)  A and C are true statements. 
A)  Sprues may be made of wax, plastic, or metal. 
B)  Sprues are placed on cusps of the wax pattern. 
C)  Sprues are placed in the central groove of the wax pattern. 
D)  A and B are true statements. 
E)  A and C are true statements.

Question 2

Before investing,a surfactant may be used to:

Accepted Answer

A)  wet the ceramic-paper liner. 
B)  liquefy the investment material. 
C)  aid the flow of the investment material over the wax pattern. 
D)  reduce residual stress in the wax pattern. 
A)  wet the ceramic-paper liner. 
B)  liquefy the investment material. 
C)  aid the flow of the investment material over the wax pattern. 
D)  reduce residual stress in the wax pattern.

Question 3

An invested wax pattern is allowed to set for at least _____ before burnout.

Accepted Answer

A)  10 minutes 
B)  45 minutes 
C)  12 hours 
D)  24 hours 
E)  1 week 
A)  10 minutes 
B)  45 minutes 
C)  12 hours 
D)  24 hours 
E)  1 week

Question 4

The amount of thermal expansion of the investment is regulated by:

Accepted Answer

A)  type of silica refractory used. 
B)  temperature used during burnout. 
C)  type of inlay wax used. 
D)  A and B. 
E)  B and C. 
A)  type of silica refractory used. 
B)  temperature used during burnout. 
C)  type of inlay wax used. 
D)  A and B. 
E)  B and C.

Question 5

A sprue forms a channel in the investment through which the molten alloy travels to form the restoration.Sprues often are wax but also may be plastic or even metal.

Accepted Answer

A)  Statement 1 is correct; statement 2 is correct. 
B)  Statement 1 is correct; statement 2 is incorrect. 
C)  Statement 1 is incorrect; statement 2 is correct. 
D)  Statement 1 is incorrect; statement 2 is incorrect. 
A)  Statement 1 is correct; statement 2 is correct. 
B)  Statement 1 is correct; statement 2 is incorrect. 
C)  Statement 1 is incorrect; statement 2 is correct. 
D)  Statement 1 is incorrect; statement 2 is incorrect.

Question 6

A casting ring:

Accepted Answer

A)  retains the investment while it sets. 
B)  is commonly lined with a dry ceramic-paper liner. 
C)  is commonly lined with a wet ceramic-paper liner. 
D)  both A and B. 
E)  both A and C. 
A)  retains the investment while it sets. 
B)  is commonly lined with a dry ceramic-paper liner. 
C)  is commonly lined with a wet ceramic-paper liner. 
D)  both A and B. 
E)  both A and C.

Question 7

If molten alloy were cast into a ring at room temperature,the:

Accepted Answer

A)  casting would be much larger than the die. 
B)  margins of the casting would be complete. 
C)  investment would likely crack. 
D)  investment would partially decompose. 
A)  casting would be much larger than the die. 
B)  margins of the casting would be complete. 
C)  investment would likely crack. 
D)  investment would partially decompose.

Question 8

The type of flux used during dental castings depends upon all of the following except the:

Accepted Answer

A)  liquidus of the casting alloy. 
B)  type of heat source used to melt the alloy. 
C)  type of casting alloy. 
D)  type of investment. 
E)  type of wax. 
A)  liquidus of the casting alloy. 
B)  type of heat source used to melt the alloy. 
C)  type of casting alloy. 
D)  type of investment. 
E)  type of wax.

Question 9

Phosphate-bonded investments:

Accepted Answer

A)  use a gypsum investment binder. 
B)  use a silica refractory. 
C)  are used for ceramic-alloy restorations and many partial denture frameworks. 
D)  both A and B. 
E)  both B and C. 
A)  use a gypsum investment binder. 
B)  use a silica refractory. 
C)  are used for ceramic-alloy restorations and many partial denture frameworks. 
D)  both A and B. 
E)  both B and C.

Question 10

The total expansion of the investment is the sum of the hygroscopic and thermal expansions.Investments rely primarily on hygroscopic expansion to compensate for casting shrinkage of the metal.

Accepted Answer

A)  Both statements are true. 
B)  Both statements are false. 
C)  The first statement is true; the second statement is false. 
D)  The first statement is false; the second statement is true. 
A)  Both statements are true. 
B)  Both statements are false. 
C)  The first statement is true; the second statement is false. 
D)  The first statement is false; the second statement is true.

Question 11

For some gold-based alloys,bench cooling produces a _____,_____ state of the alloy referred to as a(n)_____.

Accepted Answer

A)  harder; weaker; ordered solution 
B)  harder; stronger; ordered solution 
C)  softer; weaker; eutectic 
D)  softer; stronger; eutectic 
A)  harder; weaker; ordered solution 
B)  harder; stronger; ordered solution 
C)  softer; weaker; eutectic 
D)  softer; stronger; eutectic

Question 12

Which is the correct order of operations to construct a cast appliance?

Accepted Answer

A)  Wax pattern, investment, sprue, burnout, cast 
B)  Investment, wax pattern, sprue, cast, burnout 
C)  Wax pattern, sprue, cast, burnout, investment 
D)  Wax pattern, sprue, investment, burnout, cast 
A)  Wax pattern, investment, sprue, burnout, cast 
B)  Investment, wax pattern, sprue, cast, burnout 
C)  Wax pattern, sprue, cast, burnout, investment 
D)  Wax pattern, sprue, investment, burnout, cast

Question 13

If the molten metal and the investment material are too far apart in temperature:

Accepted Answer

A)  the metal will solidify too quickly. 
B)  there will be too much shrinkage. 
C)  the investment will crack. 
D)  the metal will crack. 
A)  the metal will solidify too quickly. 
B)  there will be too much shrinkage. 
C)  the investment will crack. 
D)  the metal will crack.

Question 14

Pickling a casting:

Accepted Answer

A)  removes surface oxides. 
B)  uses hot calcium carbonate. 
C)  uses hot sulfuric acid. 
D)  A and B. 
E)  A and C. 
A)  removes surface oxides. 
B)  uses hot calcium carbonate. 
C)  uses hot sulfuric acid. 
D)  A and B. 
E)  A and C.

Question 15

The blowtorch used to heat casting alloys:

Accepted Answer

A)  may operate on a combination of natural gas and compressed air for low-temperature alloys. 
B)  may operate on a combination of natural gas and oxygen for higher-temperature alloys. 
C)  must heat the alloy sufficiently to ensure a low viscosity of the alloy for casting. 
D)  A, B, and C. 
E)  A and C. 
A)  may operate on a combination of natural gas and compressed air for low-temperature alloys. 
B)  may operate on a combination of natural gas and oxygen for higher-temperature alloys. 
C)  must heat the alloy sufficiently to ensure a low viscosity of the alloy for casting. 
D)  A, B, and C. 
E)  A and C.

Question 16

The purpose of a sprue is to:

Accepted Answer

A)  form the occlusal surface of a casting. 
B)  form a channel in investment through which the molten alloy travels to form the casting. 
C)  form the proximal surface of a casting. 
D)  reduce the metal content of a casting. 
A)  form the occlusal surface of a casting. 
B)  form a channel in investment through which the molten alloy travels to form the casting. 
C)  form the proximal surface of a casting. 
D)  reduce the metal content of a casting.

Question 17

If a metal sprue is used,it must be:

Accepted Answer

A)  coated with a surfactant. 
B)  removed before casting. 
C)  burned out with the wax. 
D)  secured in the investment. 
A)  coated with a surfactant. 
B)  removed before casting. 
C)  burned out with the wax. 
D)  secured in the investment.

Question 18

Which of the following statements is(are)true concerning expansion of an investment material?

Accepted Answer

A)  Expansion of the investment from added water is called hygroscopic expansion. 
B)  Investments are designed to expand to compensate for casting shrinkage. 
C)  Expansion of the investment from heat is called thermal expansion. 
D)  A, B, and C are true statements. 
E)  A and C are true statements. 
A)  Expansion of the investment from added water is called hygroscopic expansion. 
B)  Investments are designed to expand to compensate for casting shrinkage. 
C)  Expansion of the investment from heat is called thermal expansion. 
D)  A, B, and C are true statements. 
E)  A and C are true statements.

Which of the following statements is(are)true of sprues?

Before investing,a surfactant may be used to:

An invested wax pattern is allowed to set for at least _____ before burnout.

The amount of thermal expansion of the investment is regulated by:

A sprue forms a channel in the investment through which the molten alloy travels to form the restoration.Sprues often are wax but also may be plastic or even metal.

A casting ring:

If molten alloy were cast into a ring at room temperature,the:

The type of flux used during dental castings depends upon all of the following except the:

Phosphate-bonded investments:

The total expansion of the investment is the sum of the hygroscopic and thermal expansions.Investments rely primarily on hygroscopic expansion to compensate for casting shrinkage of the metal.

For some gold-based alloys,bench cooling produces a ___,_ state of the alloy referred to as a(n)___.

Which is the correct order of operations to construct a cast appliance?

If the molten metal and the investment material are too far apart in temperature:

Pickling a casting:

The blowtorch used to heat casting alloys:

The purpose of a sprue is to:

If a metal sprue is used,it must be:

Which of the following statements is(are)true concerning expansion of an investment material?

Introduction to Restorative Dental Materials

Properties of Materials

Preventive Dental Materials

Direct Esthetic Restorative Materials

Dental Amalgam

Finishing, polishing, and Cleansing Materials

Cements

Impression Materials

Model and Die Materials

Waxes

Casting Alloys, wrought Alloys, and Solders

Polymers in Prosthodontics

Dental Ceramics

Dental Implants

Filters

Exam 12: Casting and Soldering

Which of the following statements is(are)true of sprues?

Before investing,a surfactant may be used to:

An invested wax pattern is allowed to set for at least _____ before burnout.

The amount of thermal expansion of the investment is regulated by:

A sprue forms a channel in the investment through which the molten alloy travels to form the restoration.Sprues often are wax but also may be plastic or even metal.

A casting ring:

If molten alloy were cast into a ring at room temperature,the:

The type of flux used during dental castings depends upon all of the following except the:

Phosphate-bonded investments:

The total expansion of the investment is the sum of the hygroscopic and thermal expansions.Investments rely primarily on hygroscopic expansion to compensate for casting shrinkage of the metal.

For some gold-based alloys,bench cooling produces a _____,_____ state of the alloy referred to as a(n)_____.

Which is the correct order of operations to construct a cast appliance?

If the molten metal and the investment material are too far apart in temperature:

Pickling a casting:

The blowtorch used to heat casting alloys:

The purpose of a sprue is to:

If a metal sprue is used,it must be:

Which of the following statements is(are)true concerning expansion of an investment material?

Introduction to Restorative Dental Materials

Properties of Materials

Preventive Dental Materials

Direct Esthetic Restorative Materials

Dental Amalgam

Finishing, polishing, and Cleansing Materials

Cements

Impression Materials

Model and Die Materials

Waxes

Casting Alloys, wrought Alloys, and Solders

Polymers in Prosthodontics

Dental Ceramics

Dental Implants

Filters

For some gold-based alloys,bench cooling produces a ___,_ state of the alloy referred to as a(n)___.