The maximum carbon content of steel used in dentistry is__________________?
A. 19%
B. 2%
C. 1.7%
D. 4%
Metallurgy
Flux is used during casting to________________?
Flux is used during casting to________________?
A. Remove the oxides formed on the gold alloy
B. Lower the melting point
C. Replace casting wax
D. Speed the burnout process
Resistance to corrosion in a cobalt-chrome casting is due to presence of_______________?
Resistance to corrosion in a cobalt-chrome casting is due to presence of_______________?
A. High quality iron
B. Chrome
C. Cobalt
D. Nickel
Which is the use of boxing an impression______________?
Which is the use of boxing an impression______________?
A. Ease of construction of denture
B. Preserving the sulci
C. Ease of pouring an impression
D. All of the above
Gap between true end of casting ring and wax pattern should be______________?
Gap between true end of casting ring and wax pattern should be______________?
A. ¼ inch
B. ½ inch
C. 3/8 inch
D. one inch
Addition of large amounts of platinum to a casting gold alloy will________________?
Addition of large amounts of platinum to a casting gold alloy will________________?
A. Decrease its strength and ability to be hardened
B. Decrease its tarnish resistance
C. Increase its fusion temperature
D. Redden the alloy
All of the following statements about cast cobalt alloy are true EXCEPT_____________?
All of the following statements about cast cobalt alloy are true EXCEPT_____________?
A. They have a modulus of elasticity twice that of gold alloys
B. They are more rigid than gold alloys
C. They have higher ductility than gold alloys
D. They have a lower proportional limit than gold alloys