Patients who are familiar with the treatment of dental cavities no doubt know that there have been some changes over the last few decades in how teeth are filled. Among the most common kinds of fillings are dental amalgams, more commonly known as silver fillings, and composite resins, which are the tooth-colored fillings patients are choosing more often these days, often for aesthetic reasons. There are pros and cons for each of these kinds of fillings, and we will discuss them here.
Dental amalgams, or silver fillings, have been in use for 150 years and are found in the mouths of hundreds of millions of people worldwide. This type of filling is made by mixing elemental mercury with an alloy composed of copper, silver, and tin. To prepare a tooth for this type of filling, the dentist removes all traces of tooth decay from the tooth with a drill and then shapes the tooth for the filling. The next step is to mix the alloy and the mercury together and place it into the cavity where it hardens into a “silver” filling.
The strengths of dental amalgams are two: they are both strong and long-lasting, and they are comparatively inexpensive. Over time they have proved themselves a good solution to the common problem of tooth decay. From the perspective of aesthetics, however, they leave something to be desired. Many people have also expressed concern about the use of mercury in these types of fillings. While the form of mercury used in dental amalgams – elemental mercury – is not the same kind found in fish and is not absorbed by the body in the same way, the worry is that some patients will have very adverse reactions to it and become ill.
Fortunately, allergies to elemental mercury are very rare, and the FDA considers the use of dental amalgams to be safe for adults and children ages 6 and up. Dentists do not recommend removing amalgams and replacing them with composites unless the filling itself is compromised. This would result in the loss of tooth structure and be worse for the patient’s overall health.
For the treatment of new cavities, however, the more aesthetic choice is to opt for composite resins. These are made of a tooth-colored plastic and glass mixture that can be tinted to match a patient’s natural enamel. A dentist will prepare the tooth in the same way as with dental amalgams, but install the composite resin filling in layers, using a specialized light to harden it. In addition to blending better with a patient’s natural tooth, composite resins also bond with the tooth and support its natural structure.
Composite resin fillings are, unfortunately, more expensive than dental amalgams, and insurance companies will often pay only what the least expensive alternative costs, with the patient responsible for the rest. Additionally, composites do not appear to perform quite as well as silver fillings long term. Some patients also experience some tooth sensitivity with composite resin fillings.
If you have questions about the overall performance or safety of the different options for repairing cavities, please talk to your dentist. Your dental history is unique and may there may be considerations to discuss. We at Dental Associates of West Michigan are happy to discuss your concerns with you to come up with the best plan for your dental health.