Thanks to technological advances, dental patients today have several choices when it comes to selecting materials to fill cavities. They can choose between amalgam and composite fillings, which are often referred to as “silver” and “white,” respectively, or tooth-colored porcelain fillings.
Depending on the type of filling needed, and in concert with your dentist, making the choice is easier when you understand the differences of each material. Here’s the rundown:
Amalgam fillings, while reliable and time-tested, are being used less frequently due to the fact that composite materials have improved tremendously. These “silver” fillings are really silver amalgams containing a mixture of silver-tin alloy, copper, and mercury. They have been used for 150 years and are inexpensive and not technique-sensitive. They can last for two decades or longer.
The safety of the mercury in amalgam fillings is a question that has often been raised. Mercury is used in amalgam because it helps make the filling material pliable. When it is mixed with an alloy powder, it creates a compound that is soft enough to mix and press into the tooth. But it also hardens quickly and can withstand the forces of biting and chewing.
Many studies on the safety of amalgam fillings have been done. In 2009, the U.S. Food and Drug Administration evaluated this research and found no reason to limit the use of amalgam. The FDA concluded that amalgam fillings are safe.
“FDA has reviewed the best available scientific evidence to determine whether the low levels of mercury vapor associated with dental amalgam fillings are a cause for concern,” the agency writes. “Based on this evidence, FDA considers dental amalgam fillings safe for adults and children ages 6 and above.”
There are ongoing reviews evaluating the safety and effects of dental amalgams. The FDA does caution that if you are allergic or sensitive to mercury or any of the other components of amalgam, that you should choose another type of filling.
The World Health Organization has recommended that dental amalgam be phased out as part of an effort to reduce human exposure to mercury.
A composite filling is tooth-colored and therefore more esthetic, but the advantages are more than just cosmetic. Composite fillings are more conservative, meaning they can sometimes be placed with less tooth removal, according to the American Dental Association. They can also be used in smaller areas whereas an amalgam filling has a minimum size requirement. Additionally, composite fillings do not cause tooth staining over time.
The ADA notes, however, that composite fillings tend to have a shorter life span and require a completely dry environment, which can be difficult in some patients with above average saliva output or sensitive gums that bleed. However, when composites are placed correctly, they can last just as long as amalgams.
Composites can also be more expensive than amalgams and some insurance companies may cover composites only up to the price of an amalgam, and then require the patient to pay the difference.
Porcelain is used for larger restorations when much of the tooth is missing. It is used for inlays, onlays (also called “partial crowns”) and full crowns. Porcelain combines beauty and strength, reinforcing teeth when traditional fillings are not an option. The all-porcelain solution requires less tooth removal than traditional porcelain fused to metal crowns and contains no metal. New ceramic materials are durable and less prone to breakage than older ceramic materials, according to the ADA.
Inlays are restorations that are smaller than crowns or onlays, as they do not cover the biting surface of the tooth. Onlays partially cover the tooth and crowns conceal the entire tooth surface above the gum line. Many offices can now make these restorations in one visit, which is more convenient for the patient.
If you are in the market for new fillings, speak with Dr. Meyers to discuss what option best fits your needs.