WorksheetsComposite & Amalgam
Total questions: 20
Worksheet time: 10mins
Bonding of composite resins to tooth structure is by
Covalent bond
Ionic bond
Micro-Mechanical bond
Hydrogen bond
Which of the following will impart radiopacity to composite resins?
Coupling agent
Organic matrix
Silica glass
Strontium glass
Which of the following phases of dental amalgam has maximum strength?
Ag2Hg4
Ag3Sn
Cu6Sn5
Sn8Hg
Which of the following acts as a scavenger of oxygen during manufacturing of amalgam alloy powder?
Silver
Copper
Mercury
Zinc
Which of the following is NOT an advantage of Eames technique?
High strength
More plastic & good adaptation
No squeezing of excess mercury
Sets quickly
Which of the following is the advantage of low copper amalgam alloys as compared to high copper alloys?
Corrosion products seal the margins
Has low creep
Have higher 1hr strength
Less marginal breakdown
What is the half-life of mercury in blood?
15 to 30 days
30 to 45 days
45 to 60 days
60 to 75 days
Which of the following statement is true?
Lathe cut amalgam require less mercury and has high 1 hr. strength
Lathe cut amalgam require more mercury and has high 1 hr. strength
Spherical amalgam requires less mercury and has high 1 hr. strength
Spherical amalgam requires more mercury and has high 1 hr. strength
Which of the following fillers in composite resins have negative coefficient of thermal expansion?
Beta-eucryptite
Fused quartz
Ytterbium fluoride
Zinc glasses
Which of the following correctly denotes the filler size of midi-filled composite resins?
0.01 to 0.1 µm
0.1 to 1.0 µm
1.0 to 10.0 µm
10 to 100 µm
What is known as a measure of the percentage of carbon-carbon double bonds that have been converted to single bonds to form a polymeric resin?
Degree of conversion
Depth of cure
C.
Gelation ratio
Polymer- monomer ratio
Which of the following constitutes the hybrid layer in dentin bonding?
Adhesive, Primer & smear layer
Etched dentin, collagen network and resin tags
Normal dentine, Adhesive & composite
Primer, Adhesive & composite
By increasing the percentage of which metal, the strength and hardness of amalgam increases?
Ag
Cu
Hg
Zn
What is the most common corrosion products found with conventional amalgam alloys?
Oxides and chlorides of copper
Oxides and chlorides of mercury
Oxides and chlorides of silver
Oxides and chlorides of tin
Which of the following is NOT the benefit of using fillers in dental composites?
Reinforcement of the matrix resin, resulting in increased hardness, strength, and decreased wear
Improved workability by increasing viscosity (liquid monomer plus filler yields a paste consistency)
Increase in water sorption, softening, and staining
Increased radiopacity and diagnostic sensitivity through the incorporation of strontium (Sr) and barium (Ba) glass and other heavy metal compounds that absorb x-rays
What is the C-factor for a class III restoration?
5
2
1
0.5
3. Which of following factors DOESN’T affect the finish and polish of a composite restoration significantly?
Curing light
Delayed versus immediate finish
Surface coating and sealing
The type of material
The thickness of a resin that can be converted from a monomer to a polymer under a specific light-curing condition is known as
C – factor
Degree of conversion
Degree of polymerization
Depth of cure
Which of the following is NOT true regarding creep of amalgam alloys?
Gamma phase deforms plastically
Presence of Gamma 2 phase increases creep
Eta phase acts as barrier to deformation of gamma 1 phas
Higher creep rate for low copper amalgam
Which of the following is correct for amalgam restoration?
They have More compressive strength and Less Tensile strength
They have More compressive strength and Tensile strength
They have less compressive strength and Less Tensile strength
They have less compressive strength and more Tensile strength
