Quiz on Properties of Dental Amalgam

What is the initial contraction in the first 20 minutes of dental amalgam setting due to?

• Crystal growth of new phases

• Reaction of mercury with the alloy particles

• Solution of the alloy particle's surfaces into mercury

• Diffusion of mercury between the alloy particles

What is the main characteristic of dental amalgam in terms of strength?

• Ductile

• Elastic

• Brittle

• Flexible

What is the time-dependent plastic deformation due to stress application below the yield stress before complete setting of amalgam called?

• Expansion

• Creep

• Flow

• Contraction

How can marginal seal be obtained in dental amalgam?

• Low copper amalgam alloy

• High mercury/alloy ratio

• No corrosion products

• Good condensation

What is the viscoelastic nature of dental amalgam responsible for?

• Bond to tooth structure

• Flow and creep

• Dimensional changes

• Strength

What is the effect of creep in dental amalgam?

• Marginal breakdown

• All of the above

• Gingival overhangs

• Occlusal overhangs

How does dental amalgam develop its strength?

• Within 1 hour

• After 2 weeks

• Instantly after setting

• Slowly within 7 days

What is the purpose of using a high copper uni-compositional dental amalgam alloy?

• Decrease creep

• Increase flow

• Enhance bond to tooth structure

• Improve dimensional changes

What is the main advantage of the new Amalgam bonded system containing 4-META?

• No mechanical retention

• Decrease in strength

• Reduction of post operative sensitivity

• Increase in corrosion

How can corrosion in dental amalgam be reduced?

• Low mercury alloy ratio

• Increased porosity

• Marginal breakdown

• High copper amalgam alloys