Dental Amalgam

Dental Amalgam is a commonly used dental filling that has been used for over 150 years. It is a self-hardening mixture of elemental mercury (43-54%) and an alloy powder (46-57%) composed mainly of silver, tin, and copper. Amalgam has many advantages over other restorative material, such as low cost, strength, durability, and bacteriostatic effects.

Amalgam is used in dentistry for a number of reasons. It is relatively easy to use and manipulate during placement; it remains soft for a short time so it can be packed to fill any irregular volume, and then forms a hard compound. Amalgam possesses greater longevity than other direct restorative materials, such as composite. On average, most amalgam restorations serve for 10 to 12 years, whereas resin-based composites serve for about half that time. However, with recent improvements in composite material science and a better understanding of the technique-sensitivity of placement, it should be noted that this difference is decreasing.

There are circumstances in which composite (white fillings) serves better than amalgam; when amalgam is not indicated, or when a more conservative preparation would be beneficial, composite is the recommended restorative material. These situations would include small occlusal restorations, in which amalgam would require the removal of a more sound tooth structure, as well as in “enamel sites beyond the height of contour.”

Disadvantages of Silver fillings: Silver fillings have many drawbacks. They are gray, not tooth colored. May darken as it corrodes; may stain teeth over time. Requires removal of some healthy tooth.  In larger amalgam fillings, with age, the metal of a silver filling expands, contracts, and can split. The edges of the silver filling can wear down, become weak or break. This results in the tooth not being protected and lets cavities get started once again. The remaining tooth may weaken and fracture. They can corrode, leak and cause stains on your teeth and gums.

An informed patient in consultation with his or her dentist best determines the options regarding any dental treatment.  If you need a filling, Dr. McElfish can advise you about the available options.   Remember: ultimately, it is the patient’s decision in consultation with the dentist as to what type of filling is used.

It is important to understand that amalgam is not mercury; rather amalgam alloy, the components of which include mercury.  The alloy has entirely different properties than mercury.  So weather you are considering its effects on the body or on the environment, you can not compare exposure to amalgam to an equivalent amount of mercury.

The American Dental Association Council on Scientific Affairs, The Food and Drug Administration, The National Institutes of Health, The US Public Health Service, The Centers for Disease Control, and  The World Health Organization, all have concluded that amalgam restorations are considered safe and effective for tooth restoration.

For more information about oral health issues, visit the American Dental Association Web site at