C14    Contrast the similarities or differences between undertriturated and overtriturated amalgams.

Undertriturated amalgam:

Looks somewhat grainy and dull. Crumbles when handled. Results in a weak and porous restoration, which also corrodes faster than properly triturated or overtriturated amalgams.

Overtriturated amalgam

Shiny and plastic. The mixed amalgam is also rather warm (hot) when it is removed from the capsule. Sets too fast.

Properly triturated amalgam

Can be warm (not hot) when it is removed from the capsule. Looks shiny and is plastic. Setting time in accordance with the instructions from the manufacturer. A properly triturated amalgam is shown below.

Factors affecting trituration

• Different amalgam alloys require different trituration times
• Different amalgam volumes require different trituration times
• Different triturator work differently and require different trituration times
• Triturators may be influenced by changes in voltages
• Different capsules require different trituration times