At Greenwood Dental we view the newer composite (white) fillings as a superior option to the older Mercury Fillings.
A silver (or amalgam) filling is a mixture of approximately 50% silver/tin alloy and 50% mercury. After tooth decay is removed and cleaned, this gray colored material is packed into the tooth and shaped. Silver fillings have been used for more than 125 years. Their biggest advantage is that they are quickly placed. The filling material itself is also relatively durable.
The disadvantage of silver fillings is that they do not bond (stick) to the tooth structure. This requires the additional area of the healthy tooth to be removed creating a chamber that is smaller at the surface of the tooth and wider inside. This keeps the filling from falling out of the tooth. The problem is that the creation of this chamber requires the removal of more healthy tooth structure than is necessary. This weakens the tooth and predisposes it to fracture when biting into hard items. Since fillings will break down from normal wear, they will eventually need to be replaced, and this will require the removal of even more healthy tooth structure.
The alternative to silver fillings are composite (white) fillings, by bonding directly to the tooth composite fillings limit the removal of healthy tissue and pose no known environmental risk. In cases of extensive decay, inlays/onlays or crowns are a much better restoration.