We consider very carefully, the type of metal tube we choose when building homes or any building construction. What about the metals in our mouths? We all know metals are used to fill teeth. Most people don’t consider what types of metals are used to fill their teeth, like they do when building their homes.

“I work for the Gas Company, and if I put copper tubing next to a galvanized iron, steel or other metal tube, I’d get fired,” said Gary Webber.

Gary, my patient who worked for the Gas Company in Southern California, made this statement. He went on to say this would cause a dissimilar metal corrosion that would lead to rot where they contacted. Without knowing or having considered tubing made of different metals for homes, what he said made sense to me. I was explaining the difference between all the metals and filling material choices for fillings and crowns in the mouth when Gary offered this analogy to me. He asked, “Do dentists put different metals in the mouth next to each other so they contact?”

Yes they do, was my answer.

There are many metals used for dental restorations, including crowns (caps) and fillings:

* Aluminum (used rarely)
* Cadmium
* Cobalt
* Chrome
* Gold
* Mercury
* Nickel
* Copper
* Palladium
* Platinum
* Silver
* Zinc

A study published in the Journal of American Dental Association in 2003 by Richard Walker, entitled “Galvanic Interaction Between Gold and Amalgam, Effect of Zinc, Time and Surface Treatments” reports that “contact between gold and dental amalgam restorations in the oral environment may elicit sensitivity from galvanic current flow between the two restorations. D.E. Snyder, in ‘Incidence of painful electrogalvanism,’ Journal of General Dentistry, 1987 reported the incidence of painful oral electrogalvanism from a variety of dissimilar metals to be 0.4 percent, or 68 of the 16, 929 amalgam restorations placed by senior dental students in a two-year period.”

In other words, if you have different metals in your mouth, such as a gold cap next to an amalgam (silver/mercury) filling, currents may be generating between them. The illustration to help you understand this better is a battery. The positive terminal (with the + sign) is the cathode (gold) while the negative (with the – sign) is the (amalgam). The article went on to explain when the dissimilar metals contact, the electrical charge flow is concentrated in the tooth before it spreads to the surrounding tissues. This dental galvanic current can cause tooth pain. During amalgam’s first 24 hours in the mouth, the pain from galvanic current can be severe; but with time, the pain may subside. This reduction of pain may be due to corrosion on the surface of the amalgam filling.

Take a look in your mouth; if you have gold next to a silver filling, you may want to change them to similar metals or to non-metal restorations, when they need replacing. With the use of other potentially harmful current generating devices surrounding us, such as cell phones, microwaves, and computers, the mouth should be the last place to consider generating currents. According to the World Health Organization, electromagnetic fields (EMF) of all frequencies represent one of the most common and fastest growing environmental influences, about which anxiety and speculation are spreading. All populations are now exposed to varying degrees of EMFs, and the levels continue to increase as technology advances.

Amalgam, or as it is commonly called “silver mercury,” is approximately 65-85 percent mercury and the rest a mixture of other metals including zinc, copper and nickel, depending on the manufacturer. The controversy about mercury in dental fillings has been argued from the beginning when it was first created. There are individuals who are allergic to mercury or some of the other metals in amalgam or even gold. Scientific literature and the American Dental Association has adopted the view that once the mixture of mercury and the other metals harden or set, there isn’t enough mercury left in its elemental form to cause harm to tissues and organs. Other views shared in the holistic dental organizations maintain that mercury is released and even the slightest concentration can be hazardous. Amalgam has been linked to neurological problems, gastrointestinal problems, sleep disturbances, poor concentration, memory disturbances, fibromyalgia, chronic fatigue and other health problems.

Of course, mercury can accumulate in the tissues from a variety of sources including air and fish, just to name two. Hair testing and even blood testing has been recommended by biological dental practices as a means of detecting and measuring mercury in the body. As a result, non-mercury fillings have been across the board recommended, with some dentists having their licenses revoked due to unethical treatment. Testimonials were written about serious chronic illness having been reversed with the removal of amalgam fillings or extraction of root-canaled teeth. Unfortunately, the results were not documented through valid scientific methods.

In my experience, I never witnessed a miraculous cure from removing amalgam fillings. There are those individuals who truly have sensitivity to mercury. Most of these individuals also have other health issues and their immune system is compromised. If you aren’t sure whether you have an allergy to mercury, the next time a filling needs to be replaced change it to non-mercury filling. Amalgam fillings do have problems, for example, they can shrink causing bacteria to grow under the filling. I also want to warn you against taking all your mercury fillings out at once. Not only can this be traumatic and costly, but will cause exposure to mercury vapor, especially if you have many of the mercury type of fillings in your mouth. Take them out based on need. Determine which requires attention first.

You also have choices for the types of crowns to use. There are many types available including precious metal (mostly gold and platinum) to non-precious (no gold). I don’t recommend non-precious, if at all possible. The best way to compare the two types is to compare 14-carat gold jewelry with costume jewelry (non-precious). If you leave costume jewelry on 24/7, you may develop an allergic reaction to the metal—same with non-precious metal in the mouth.

Implants are another type of restoration to replace missing teeth that involve metals, and should be carefully considered. Implants involve major surgery. One must have healthy bone and gums to be a candidate for implants, although there are types that can be used in patients who do not have enough bone. Bone grafts can also help replace bone. There are many types available. Some are placed in a single stage, while others take a few steps from start to finish. Titanium is the most common type of metal used for the actual implant. Specialists that place implants include periodontists (gum specialists) and oral surgeons. If you are considering implants, do your homework and get two or three opinions before deciding, and ask for all your options for replacing missing teeth. Some of the choices include:

* Implant: An artificial tooth is surgically placed in the jawbone. A period of three-six months is needed for healing before the treatment is completed. You need strong bone and healthy gums for this to work. The types available include:
1. “Endosseous” is an implant that is placed directly in the bone, and is referred to as a “root-form” implant. These look like screws.
2. “Sub-Periosteal” implant is used in patients who do not have enough bone to support the endosseous implant. These are placed over the jaw rather than in it.
3. Another category is the “Plate or Blade-Form” implant that uses one or two metal prongs and a plate, which are placed in the jaw. The prongs stick up into the mouth and hold the artificial tooth in place.
4. The “Ramus-Frame” implant is for patients with thin lower jawbone. These are placed in the back corners of the mouth and near the chin. These help to hold dentures (full or partial) in place.

* Bridge: It literally bridges the gap where there is a missing tooth or teeth. Each tooth on either side of the gap is shaped and is connected by a false tooth called a “pontic.” The bridge can be supported by natural teeth or implants. A bridge can’t be removed.

* A partial denture is removable and is held in place by either clasps placed on teeth, or implants. The base and clasps are frequently metal, while other parts are acrylic and made to match the color of the gums. The base and clasps can be made of acrylic, base metal, titanium, cobalt-chromium or gold. Even wrought wire is used for some clasps, however these are usually for temporary use only. What type wet choose will depend more on biomechanical stability than allergy or any type of galvanic reaction to a particular material. Studies need to be done to evaluate how these metals in contact with metals placed on individual teeth may cause reactions in the mouth.

With dental treatment, such as replacing missing teeth, unfortunately it’s not good to wait too long, since teeth may shift causing a domino effect of other problems. Don’t procrastinate. Consider the options, make a decision and get treatment.

Source: Total Health magazine, Volume 29, No. 3