Silver fillings are called Amalgams. Nobody pours melted silver into your tooth, rather the silver is ground into a fine powder and mixed with Mercury a liquid metal. This concoction when violently mixed and turns from a liquid/putty into a solid in minutes. These amalgams maybe as much as 65% mercury and are very controversial because of the mercury. Pure Mercury is clearly a poison. Yet, many of us have these in our mouths without any perceived or observable negative effects.

Amalgam fillings are the most efficient, least expense restoration available. They also last much longer than white fillings. The country of Sweden has totally banned mercury containing fillings, while my American Dental Association accepts it as an effective therapeutic material.

The most recent metallurgy has reduced the mercury content and added zinc, platinum, copper and other trace metals into the mix to help bind the mercury. Still many blame, auto-immune diseases and worse on this type of restoration.

One thing for certain – no filling lasts forever! Just like the tires on your car they wear out. Additionally, all metals corrode and then break down into their components. For example, we have all seen iron or chrome rust. There is no pain, warning or signal when your amalgam fillings start to wear out. Sometimes they will turn from silver to dark grey or even black. I believe that when an amalgam is corroding or wearing out it is time to replace it. A defective amalgam filling can act like a metal wedge in a log, causing splitting of the tooth and fracture or worse. I have seen many amalgam restorations that are decades old and still doing well.

White or ceramic resin fillings are made from plastics, fine glass particles and binders similar to epoxy. The white fillings from 35 years ago did not match the teeth and did not last very long. Again the material scientists have improved on this greatly. Your dentist is faced with the choice of a new generation of supposedly improved material every year. There are dozens of different brands with slightly different chemistry in each. Still, white fillings are much more challenging to install than silver fillings and are more expensive. In most offices, they are more profitable than silver fillings. In my office, I explain that these fillings may need to be replaced every 5-10 years depending on many conditions out of our control. Today’s ceramic resin bonded fillings can come very close to matching our natural tooth colors or shade.

Dr. Alan Ross, Keene Family Dental, 67 Mechanic Street, Keene, NH 03431 Phone: 603-357-6767