Material Amalgam part 1

Which of the following is a characteristic of high copper amalgam

• Produce excessive creep
• Better corrosion resistance than low copper
• Low strength
• Contain both y1 and y2 in its final microstructure

Mention indications of direct gold filling

Give reason, The pellet or foil of direct gold filling is degassed in pure ethanol flame

Enumerate advantages of direct gold filling

Enumerate disadvantages of direct gold filling

it is a Chemical reaction between the special alloy & Hg at room temperature.

• Amalgamation reaction
• chelation reaction
• gelation reaction
• none of the above

Dental amalgam: consists of

• Mercury (Hg) (Main constituent) + Any metal or alloy
• Special alloy = Ag3Sn + Copper Cu + Zinc Zn
• Special alloy + Hg
• none of the above

An alloy, whose constituents are completely soluble in the molten state; but on cooling they react forming new chemical compund

give reason intermetallic compound is brittle

high copper amalgam is characterized by elimination of

• Ag3Sn
• Ag2Hg3
• Sn8Hg
• Cu6Sn5