Jefferies: My first thoughts were that this was a preliminary report from the media and that this case needed to be looked into much more deeply to get all the accurate facts and to understand exactly what happened. This information would then need to be compared to the standards that exist for the materials used in this case in terms of their composition and performance criteria.

Based on the current available data and literature findings, the track record concerning the biocompatibility of dental materials, by and large, is exceptionally good. Very few systemic complications have been documented. Localized tissue reactions to various dental materials may also occur, but their frequency also is rare. These reactions, when they do occur, may be patient or material specific. Nevertheless, it appears the track record of the biocompatibility of dental materials, overall, is quite good. Having said that, it’s important to know the specifics of any particular instance.

Nathanson: Frankly, I thought it was totally irresponsible reporting. To the dental professional analyzing this story, the implied relationship between a bridge causing discomfort and lead exposure is utter nonsense. Exposure to lead has nothing to do with pain. My real concern is that this story may cause the public to lose confidence in their dental providers. So from that standpoint, it has the potential to stir a crisis in dentistry. We’ve seen it happen in the toy industry, in the food industry, and earlier in the pharmaceutical industry. If there were true concerns about exposure to lead, the patient should have been tested for the presence of lead in the bloodstream. There are FDA standards for lead blood levels and criteria for toxic levels. Now you have millions of Americans who saw the GMA segment terrorized by this story. This is irresponsible reporting and an unfortunate episode for dentistry.

For the record, Boston University was sent a sample of that bridge for independent testing. However, our testing equipment is not sensitive enough to detect minute quantities of lead, so we were unable to corroborate the results found by NSL testing laboratory.

DLP: The obvious question here is: Is there lead in dental porcelains?

Nathanson: Any porcelain may include metallic elements. Most porcelain stains are metallic oxides. Without these colorants dental porcelains would look monochromatic. Minute quantities of lead are therefore likely; however, the amounts of lead are extremely small. The amounts of lead leaching out of fully fired porcelains would be negligible.

Jefferies: Lead appears as a trace element in a number of polymeric and ceramic materials, including various stains and tints. Given the fact that it appears at some level in these materials and that standards and regulations for some maximum level of lead content do exist, reducing the level of this element in certain products to a level of “zero” may not be feasible. With respect to the toxicity of any element or compound, one has to understand the concentration and the bioavailability of any of these compounds and elements in terms of their ultimate effect.

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