Amalgam and safety

Question 1

Explain the potential health effects of high levels of mercury

Answer 1

• Affect kidneys and nervous system, producing signs such as mood swings, memory loss and development of tremors
• Grinding teeth, chewing and toothbrushing all increase the amount of mercury released
• Some of the vapour is breathed out, but some is breathed in, or dissolves in saliva and is swallowed. This may accumulate in certain organs, particularly kidneys
• However, the Hg level is very low, so the amount of Hg absorbed
into the body is very small
• The amount of mercury released from fillings is greatest when fillings are being inserted or removed

Question 2

Outline the recommendations for the clinical use of dental amalgam

Answer 2

• Avoid the placement or removal of dental amalgam restorations during pregnancy (first trimester), when the mother is breastfeeding, and its use in those patients with kidney disease
• Amalgam is a material suitable for larger restorations of posterior permanent teeth in children, young adults and adults
• No conclusive, scientific validated evidence currently exists to justify the removal of dental amalgam restorations to relieve certain systemic symptoms, or treat particular medical conditions (other than proven allergy)
• Only pre-capsulated amalgam is to be used

Question 3

How should the clinical setting look like when placing amalgam?

Answer 3

• Adequate ventilation
• Carpet should not be used as a floor covering
• Single use capsules
• Amalgamator should have a completely enclosed activating arm
• Mercury should not be touched with hands
• Wear mask
• Use rubber dam (especially for removal of old amalgams)
• Store amalgam scraps under water in a sealed container
• Use of high speed evacuation

Question 4

Describe the waste management of dental amalgam

Answer 4

• Dental amalgam adds to the level of mercury in the environment when it is not disposed of properly
• Stock amalgam capsules in a variety of sizes (different spills) to reduce waste
• After mixing amalgam, place the empty capsules and scrap amalgam in airtight containers that are marked “Amalgam Waste for Recycling” or “Amalgam Capsule Waste for Recycling”
• Make sure the container lids are well sealed
• When the container is full, it is recommended that mercury waste be returned to metal or precious metal recyclers for reclamation

Question 5

Explain what influences the success of amalgam restorations

Answer 5

Clinician factors
• Advise patient on prevention
• Material handling

Patient factors
• Oral hygiene, diet, fluoride
• Regular check ups

Material
• Amalgam selection: high copper