Amalgam is a safe, affordable, and durable material used predominantly to restore premolars and molars.
Although amalgam has been used in restorative dentistry for many years, you may see fewer amalgam restorations placed as a result of esthetic concerns of patients and the ongoing controversy about the safety of amalgam use for both the patient and staff.
Even if you see a minimal number of amalgam restorations being newly placed, you will surely see numerous existing amalgam restorations that remain in good condition for many years after placement.
This figure shows a lower right posterior arch isolated by means of a rubber dam (blue), a rubber dam clamp (metal ring), and rubber dam retainer (yellow plastic).
A class II restoration is one that includes both the necessary portion of the occlusal surface and the proximal surface abutting the adjacent tooth, in this case the mesial.
Ideally all teeth to be restored should be isolated with the use of a rubber dam in this manner. In reality, clinical circumstances do not always allow this.
The most convincing indication for amalgam placement continues to be when restoring an area where blood and saliva contamination is extremely difficult, beneath the gingiva, or both or in a poorly accessible, nonaesthetic region of the mouth where composites are contraindicated.
A patient who present with an amalgam allergy should be questioned about the specific reaction and how the allergy was diagnosed.
It is important to ask patients which type of restoration they prefer if choice is an option.
If the patient opts for an unfavorable choice, the discussion should be documented.
Once a restoration has been placed in the mouth, the materials used and methods followed must be documented in the patient’s chart.
The widely used Eames technique specifies a 1:1 ratio of mercury to alloy.
If you have the opportunity to work with amalgam, you may eventually be able to distinguish between brands because of how they feel when properly triturated and how workable they are during condensation and carving.
This photo displays the mercury liquid and alloy powder, separated on the left, and at various stages of mixing to produce a final amalgam for placement.
It is important to ensure that trituration is complete before amalgam is placed in a carrier for placement in the preparation. Different manufacturers call for different trituration times, depending on the components of their products.
Other variables to keep in mind: Triturating machines sometimes malfunction, and stocked amalgam capsules may reach their expiration dates before being used.
It is important to stress to patients that once amalgam is set, the mercury content is inactive.
Until the amalgam is set, though, components of the composite are toxic to tissues. The public is not aware of this because the irritating components are not commonly used words.
It may be more detrimental to remove more tooth by replacing a sound amalgam restoration than to leave it alone. The oral environment may be reexposed with removal.
It is very important to follow these guidelines for safe usage.
Discard undermixed amalgam materials.
The scrap-amalgam container should be disposed of properly, too.
Amalgam capsules come in different doses, so you should try to estimate what you need.
Avoid triturating another dose of amalgam until the dentist is ready for it.
If the restoration involves a proximal surface, a matrix band and wedge must be placed to reform the contour as necessary. The burnisher is used at this step to burnish the metal where contact will be reestablished with the adjacent tooth.
Polishing of amalgams, if desired, is is done during a subsequent appointment with the use of a polishing cup and a slow-speed handpiece.