What is Dental Amalgam (Silver Fillings)?
Most people recognize dental amalgams as silver fillings. Dental amalgam is a mixture of mercury, silver, tin and copper. Mercury, which makes up about 50 percent of the compound, is used to bind the metals together and to provide a strong, hard, durable filling. After years of research, mercury has been found to be the only element that will bind these metals together in such a way that can be easily manipulated into a tooth cavity.

Is mercury in dental amalgam safe?
Mercury in dental amalgam is not poisonous. When mercury is combined with other materials in dental amalgam, its chemical nature changes, so it is essentially harmless. The amount of mercury released in the mouth under the pressure of chewing and grinding is extremely small and no cause for alarm. In fact, it is less than what patients are exposed to in food, air and water.

Ongoing scientific studies conducted over the past 100 years continue to prove that amalgam is not harmful. Claims of diseases caused by mercury in amalgam are anecdotal, as are claims of miraculous cures achieved by removing amalgam. These claims have not been proven scientifically.

Why do dentists use dental amalgam?
Dental amalgam has withstood the test of time, which is why it is the material of choice. It has a 150-year proven track record and is still one of the safest, durable and least expensive materials used to a fill a cavity. It is estimated that more than 1 billion amalgam restorations (fillings) are placed annually. Dentists use dental amalgam because it is easier to work with than other alternatives. Some patients prefer dental amalgam to other alternatives because of its safety, cost-effectiveness and ability to be placed in the tooth cavity quickly.

Why don't dentists use alternatives to amalgam?
Alternatives to amalgam, such as cast gold restorations, porcelain and composite resins are more costly. Gold and porcelain restorations take longer to make and can require two dental appointments. Composite resins, or white fillings, are aesthetically appealing but require a longer time to place the restoration. It should also be known that these materials, with the exception of gold, are not as durable as amalgam.
 

What about patients allergic to mercury?
The incidence of allergy to mercury is far less than one percent of the population. People suspected of having an allergy to mercury should be tested by qualified physicians, and, when necessary, seek appropriate alternatives. Should patients have amalgam removed? No. To do so, without need, would result in unnecessary expense and potential injury to teeth.

Updated: January 2007

Academy of General Dentistry

 What is a Composite Resin (White Filling)?
A composite filling is a tooth-colored plastic and glass mixture used to restore decayed teeth. Composites are also used for cosmetic improvements of the smile by changing the color of the teeth or reshaping disfigured teeth.

How is a composite placed?
Following preparation, the dentist places the composite in layers, typically using a light specialized to harden each layer. When the process is finished, the dentist will shape the composite to fit the tooth. The dentist then polishes the composite to prevent staining and early wear.

What is the cost?
Prices vary, but composites can cost up to two times the price of a silver filling. Most dental insurance plans cover the cost of the composite up to the price of a silver filling, with the patient paying the difference. As composites continue to improve, insurance companies are more likely to increase their coverage of composites.

What are the advantages of composites?
Aesthetics are the main advantage of composites, since dentists can blend shades to create a color nearly identical to that of the actual tooth. Composites bond to the tooth to support the remaining tooth structure, which helps to prevent breakage and insulate the tooth from excessive temperature changes.

What are the disadvantages?
After receiving a composite, a patient may experience postoperative sensitivity. Also, the shade of the composite can change slightly if the patient drinks tea, coffee or other staining foods. The dentist can put a clear plastic coating over the composite to prevent the color from changing if a patient is particularly concerned about tooth color. Composites tend to wear out sooner than silver fillings in larger cavities, although they hold up as well in small cavities.

Updated: March 2007

Academy of General Dentistry