Slide 2: Strength Amalgam is one such material which gained a lot of popularity because the its strengths were adequate for normal situations within the oral cavity ( for posterior teeth, primary requirement is high tensile and compression strength) However, it is weaker in tension than in compression and it is a brittle material and may sometimes require pins embedded in the dentin as reinforcement. So, the prepared cavity design should maximize the compression forces in service and minimize tension or shear forces.
Slide 3: 2. Creep It is due to continued application of force in compression eg: gradual dimensional change due to mastication forces for a long time, that may leads to fracture. According to ADA specification no 1 Creep should be below 3%. The lower the creep value of an amalgam, the better the marginal integrity of the restoration”. eg: Creep value of Low cu amalgam is 0.8-8% & high cu is <0.1%.
Slide 4: 3. Corrosion Progressive destruction of a metal by chemical or electrochemical with its environment. The presence of small amounts of tin, silver, and copper that may dissolve in various amalgam phases has a great influence on amalgam corrosion resistance Excessive corrosion can lead to increased porosity, reduced marginal integrity, loss of strength, and the release of metallic products into the oral environment. Chemical reactions penetrate into body of amalgam eventually leads to failure of the restoration.
Slide 5: 4. Dimensional strength It refers to contraction and expansion that occurred after amalgam setting. Measured after 24 h - ve value (contract) and + ve value (expansion) http://www.dentaldiamond.ee/dental-materials/amalgam-dental-amalgam