It's my understanding that dentists doing mercury removal use a rubber dam, suction and a water spray, the water spray being necessary perhaps to settle the mercury but also to cool the tooth as it drilled because high speed drills can cause the tooth to get extremely hot, which, without the cooling water spary, can easily kill the tooth by damaging the nerve.

Any particular reason gold (opaque/nonot seet-hrough?) eye shades are used in preference to transparent plastic eye protection/goggles? Lots of people with mercury problems are also quite sensitive to 'gold', aka, jewelry quality gold mixed with other metals such as nickel.