Par 2 Review Questions Flashcards
A photo-initiator commonly used in light-cured composite resin materials is:
a. Butylated hydroxytoluene.
b. Triethylene gycol dimethacrylate.
c. Diphosphosphurous tetrafluoride .
d. Camphorquinone.
d. Camphorquinone.
Dental composite resins can be classified as:
a. Hybrid.
b. Macrofill.
c. Nanofill.
d. Microfill.
e. All of the above.
e. All of the above.
The most common cause of conventional restoration failure is:
a. Coefficient of thermal expansion.
b. Wear.
c. Fatigue.
d. Surface roughness.
c. Fatigue.
Fracture toughness is:
a. Total amount of overall stress a material can take before failing (bending force).
b. Is always equal to the elastic modulus (also known as Young’s Modulus).
c. Has no direct correlation to clinical performance of a composite resin material.
d. The amount of force required to break a composite resin in tension (tensile test).
a. Total amount of overall stress a material can take before failing (bending force).
Which one of the following fluted carbide finishing bur sequential methods will provide the most efficient removal of a large amount of composite resin material on your facial veneer restoration?
a. White band, yellow band, red band.
b. White band, red band, yellow band.
c. Red band, white band, yellow band.
d. Red band, yellow band, white band.
d. Red band, yellow band, white band.
When reducing the surface of the composite resin material in order to obtain the correct finish and polish result, which one of the following methods is correct? You must:
a. Rinse away the debris before using the next sequential gritted disk in order to produce a smooth and glossy finish to the restoration.
b. Retain the granular mixture of composite and grit from the disk in order to produce a smooth and glossy finish to the restoration.
c. Switch from a red band carbide finishing bur to an ultrafine finishing disk back to white carbide finishing diamond bur.
d. Switch from a red band carbide finishing bur to a white band and end with a yellow band carbide finishing bur.
a. Rinse away the debris before using the next sequential gritted disk in order to produce a smooth and glossy finish to the restoration.
You are having difficulty gaining access to the cervical margins of your Class III restoration to remove a minimum amount of composite resin material. You decide to use a #12 blade to gain access to the over-contoured material. Which one of the following statements is correct?
a. The finishing strip will smooth the #12 blade cleave marks making the restoration resistant to plaque accumulation.
b. The#12 blade is so sharp that you do not need to use a post-finishing strip to obtain a smooth surface of the composite resin material.
c. The #12 blade cleave marks are so sharp and minute in size that the final composite resin surface is resistant to plaque accumulation; therefore, a post finishing strip is not needed to obtain a smooth surface.
d. The finishing strip is too abrasive for the removal of composite resin material at the cervical margin.
a. The finishing strip will smooth the #12 blade cleave marks making the restoration resistant to plaque accumulation.
Manufacturers may provide shrinkage information in terms of volumetric shrinkage or linear shrinkage. Linear shrinkage is:
a. Approximately three times the volumetric shrinkage.
b. Approximately one-third of the volumetric shrinkage.
c. Approximately on-half of the volumetric shrinkage.
c. Same as volumetric shrinkage.
b. Approximately one-third of the volumetric shrinkage.
Which properties determine shrinkage STRESSES in a restoration?
a. Polymerization shrinkage of the composite
b. Elastic modulus of the composite
c. Elastic modulus of the enamel
d. Elastic modulus of the dentin
e. All of the above
e. All of the above
Which one of the following procedures is an acceptable way to reduce shrinkage stresses in light-activated composite restorations?
a. Make restorations larger, with thinner cavity walls, and the shrinkage stress in the composite will be lower.
b. Reduce post-gel shrinkage by starting the light cure at a low light intensity, and follow it up with high intensity long enough to ensure a good cure.
c. Always place large restorations in a single increment, don’t worry if composite at the bottom of the restoration cures.
d. Do not bond restorations, and there will be no shrinkage stress.
b. Reduce post-gel shrinkage by starting the light cure at a low light intensity, and follow it up with high intensity long enough to ensure a good cure.
During photo-curing of a composite resin restoration, the composite will shrink:
a. Away from the light.
b. Toward the light.
c. Toward the center of mass of the composite resin.
d. Toward where it is bonded.
e. There is no shrink with light cured composite, however there is shrinkage with auto-cured composites.
d. Toward where it is bonded.
In regards to fluted tungsten carbide finishing burs:
a. The fewer the number of flutes, the more aggressive the cutting action.
b. The larger the number of flutes, the more aggressive the cutting action.
c. The red banded burs have 20 or more flutes.
d. These burs should not be used on composite resin restorations.
a. The fewer the number of flutes, the more aggressive the cutting action.
The “white line” effect that could appear on a recently placed composite resin restoration:
a. Can be the result of polymerization shrinkage.
b. Can be the result of discontinuous voids along the cavosurface margin.
c. Can be minimized by using the correct preparation techniques using the right instruments in proper sequence.
d. Post bonding can reduce or eliminate the severity of white lines.
e. All of the above.
e. All of the above.
Composite resin materials are composed of:
a. A resin matrix. b. Filler particles. c. An initiating system. d. Silanating coating of filler particles. e. All of the above.
e. All of the above.
- Which type of dental composite resin material has the lowest viscosity?
a. Hybrid composites
b. Microfill composites
c. Flowable composites
d. Packable composites
c. Flowable composites
