Track Record: Silver amalgam has been the workhorse of restorative dentistry for over 150 years. There have been improvements in the metallurgy of silver amalgam over the years that have improved the quality of these fillings.
Durability: Well done amalgam fillings generally last decades. Some of them look really ugly, but their margins are often intact and are doing their job. The newer technology that allows us to chemically bond silver fillings increases the strength of the combination and protects the margins from leakage.
Comfort: Silver amalgams, especially the amalgams that are chemically bonded to the tooth have a higher degree of comfort after placement than most other types of fillings. The bonding procedures seem to protect the pulp especially well in bonded silver fillings.
Cost: Silver amalgams, even the bonded variation, are significantly less expensive than nearly all other types of fillings. Amalgam is usually about half to two-thirds the cost of bonded resin fillings, and about 15% to 20% as expensive as ceramic or gold inlays.
Esthetics: Silver amalgam, especially the older mixtures, tended to corrode and stain over years of use. Even the newer alloys that don't turn black or corrode as easily as the older alloys are metal and do not resemble the color of the tooth in any way.
Mercury Toxicity: There have been concerns raised about mercury toxicity in silver amalgam that have reduced the popularity of this type of filling, and outright banning for a short time in several European nations. There are dental offices throughout the country, and even in Albuquerque, that promote their practices by advertising "Mercury-free Dentistry."
I have read dozens of research pieces and articles and have come to the following conclusions regarding mercury toxicity. There is substantial evidence that if a person has a moderate number of silver fillings and chews vigorously on them, over time there will be abrasion of the fillings and mercury will be absorbed by the body. The amount of mercury absorbed by the body from the fillings is very small, and people generally absorb a lot more mercury from their diet if they occasionally eat seafood, especially deep-water fish, such as tuna, salmon and swordfish.
The anti-amalgam lobby usually suggest that silver amalgams promote multiple sclerosis, leukemia, and rheumatoid arthritis. There are volumes of research on mercury toxicity, including massive longitudinal studies over dozens of years. These scientific studies overwhelmingly demonstrate that having multiple silver fillings in your teeth does NOT increase the incidence of these three diseases, or any other disorders. The American Dental Association and the American Medical Association have declared that silver amalgams are not a health threat, and the ADA has further said that
dentists who promote amalgam alternatives because they are "better for your health" are guilty of malpractice.
I think there is a real place for silver amalgams, especially bonded amalgams, in my dental practice. I don't do them in areas where they are highly visible because of esthetic concerns, but I do them quite frequently on posterior teeth and know they are valuable services. I enjoy doing resin, gold, and ceramic fillings more because they are more esthetically satisfying, and higher tech, but silver amalgam is still a valuable filling material.