Answer to Question #8152 Submitted to "Ask the Experts"
The following question was answered by an expert in the appropriate field:
I read some articles about dental porcelain and I was told that uranium is added to dental porcelain to give dentures a natural fluorescent quality and it may result in an alpha radiation dose of 0.6 Sv per year to the gums. I believe it is much higher than the limit dose per year. Am I right? And some articles mentioned that uranium was not used anymore now, but others said it is still an issue to be worried about. I have had two porcelain onlays on my back teeth since the middle of 2008.
While it is true that in the past there was a small amount of uranium used in the glaze on porcelain denture teeth, that practice was discontinued many years ago. Today the only radioactivity found in porcelain is a very small amount found NATURALLY in the ceramic material itself.
As you are probably aware, we are surrounded by natural background radiation from many sources, including cosmic rays from outer space and naturally occurring radioactive materials in the soils and building materials in our environment. We live with these small amounts daily with no problems. The amount of background radiation that people are exposed to varies around the country, with much of the difference related to altitude. Higher altitudes receive a little more cosmic radiation than lower altitudes. However, no one has been able to find a detrimental effect for these minor variations in background dose levels.
A similar finding would be expected with the very low levels of natural radioactivity in porcelain. I personally have several porcelain crowns in my own mouth that are functioning well and are esthetically pleasing. (Porcelain is one of the most natural-looking materials to replace tooth enamel.) I have no plans on removing these crowns and I am not worried at all about the tiny amount of natural radioactivity.
Some day they may find materials to replace porcelain that have the same high structural and esthetic qualities, but right now porcelain remains an excellent material for use in crowns and onlays.
Sharon L. Brooks, DDS, MS