C13    Identify three factors which might result in less mercury being dispensed than is required.

One can buy amalgam alloy powder or amalgam powder tablets that need to be mixed manually (mortal and a pistil) or in reusable capsules using a mechanical triturator. In such cases, mercury is dispensed with a certain mercury dispenser. Potential errors in the mercury proportioning may occur during the dispensing process. These error generally result in too little mercury, and these errors are due to:

1. Dirty mercury
2. Tilting the dispenser to a 45 degree angle results in unreliable mercury:alloy ratios
3. Too little mercury in the dispenser. It should be at least half-filled.

If possible, avoid using systems that require mercury dispensing. Even though such systems are less expensive, they increase the risk for mercury contamination of the air in the dental office. It is rather easy to spill mercury during dispensing and trituration, and the reusable capsules often leak mercury during trituration.