Metal Sensitivity

It has become clear that many people can develop sensitivity to some of the metals commonly used in dental restorations. This may or may not have been the case in past years. Perhaps patients were not as sensitive to metals then, or may be the sensitivity was not recognized and diagnosed properly. There are many different kinds of metals used in dentistry. We in this office have, for years, limited your exposure to possible problems by using either materials that have fewer combinations of metals or metals that have a very low potential for sensitivity reactions.

Women appear to have more reactions to metals then men. Studies indicate that at least one woman in seven has an adverse reaction to metals. It may be related to the costume jewelry that women wear, especially earrings for pierced ears. The posts can be made of stainless steel that contains nickel. You might then notice, after some time wearing the jewelry, that your earlobes get red, dried out, or itchy. It can also be seen any place that jewelry comes into contact with your skin—wrist, neck, fingers, etc. If this is your case, you are having a metal sensitivity reaction. If you have any of these problems, it is probably advisable that you limit contact with the problem metals. This can include metals used in restoring your teeth.

At times, you could even notice a metallic taste in your mouth. This can come from silver amalgam fillings that are commonly used. Some studies show leakage of metal through the tooth into the tooth supporting structures (periodontal ligament) from the posts bonded into the tooth after the root canal treatment. These posts are entirely surrounded by tooth or restorations and are not at all in contact with the oral environment. Other oral signs of metal sensitivity include gum tissue that remains chronically red and swollen or bleeds easily where it comes into contact with the metal crown or filling.

Which metals are used in dentistry? Silver fillings (available since approximately 1816) can contain copper, silver, zinc, mercury, and other metals. At this time, we know that several countries have mandated reduced use of silver fillings because of health concerns. Crowns are composed of gold, silver, platinum palladium, and others. A post used to strengthen a tooth after a root canal is either stainless steel or titanium. Sensitivity to each of these metals has been exhibited—some more than others. Gold and titanium rank low. Titanium has been used for years for joint replacements. Pure gold is too soft to be used in dental restorations and titanium is too brittle. If you have a metal sensitivity and need a crown, it may be better to use a metal that is only gold and platinum—or perhaps a bonded ceramic material. While these options may prove to be more expensive than others, metal sensitivity should be avoided.

Nonmetal Options

Options to metal restorations include bonded resins, ceramics, and porcelain. While it is possible that you could have sensitivity to some of the bonding materials, these types of sensitivities are not at all common. The advantages of silver fillings are that they are quick to place and comparatively inexpensive. Advantages of cast metal used under porcelain crowns is similar; the metal/porcelain crowns are less expensive to make and easier to place then full ceramic varieties.

We would prefer not to use silver/mercury fillings, especially for children and women planning to have children. Bonded tooth-colored resins significantly reduce the need for drilling a tooth. They look better and help keep the tooth stronger than silver fillings. If you have a proven metal sensitivity, we will automatically choose materials with less potential for causing you problems.