Recently had a query as to whether the exposed metal on a dental crown constitutes a health risk. The short answer is that probably does not, at least no more so than if it was not exposed.You see a common dental crown has a metal substructure that covers over the remaining tooth. That metal substructure is then covered with porcelain to look like a tooth. However, whether or not the metal is totally covered makes no difference, it is still exposed either from inside or outside of the tooth. Also a porcelain-fused-to-metal crown (PFM for short) can have up to 6 different metals to create an alloy that enables the porcelain to stick to it. The photo attached shows a typical PFM crown (second tooth in from the right – the PFM crown has exposed metal on the inside near the gum area at the top of the photo. The photo also shows badly broken down mercury and plastic fillings on the other teeth).
There are really two issues that the question raises:
1. What materials are in my mouth? and
2. Are they ‘safe’ in the sense are they affecting my health?
There is a lot of controversy with the safety issue of dental materials, particularly mercury fillings. Indeed, a recently published Canadian Mercury Amalgam Risk Assessment showed that 80.4% of Canadians with mercury fillings experience a daily dose of mercury that exceeds the REL(reference exposure level) associated dose. (Canadian Health Measures Survey: 2007-2009).
Many patients are asking for materials that are considered safe for them. Some choose to have biocompatability testing done by Cliffords Consulting (www.ccrlab.com). There are other tests available to test the various dental implant materials. For those interested in determining if mercury is an issue the best test is the Quicksilver Scientific Mercury Tri-test (www.QuicksilverScientific.com). Test kits are available at our office. Call if you want more information.
With regard to the materials used for crowns. There are metal-free ceramic and zirconia materials that not only look great but are very strong. See the before and after photos below.
Please feel free to contact us at info@ClintonDentistry.com or on our Facebook page. if you wish to speak with a real person call 613 376 6652.