CHICAGO (March 27, 2008)—An Ohio TV station aired a report in late February claiming that a dental crown produced in a Chinese dental lab has tested positive for lead. There is no appropriate use for lead in manufacturing dental prosthetics.
The ADA is taking this report very seriously. However, we do want to keep it in perspective. There simply isn’t enough information available to presume that the presence of lead in dental crowns or other prostheses is widespread. An estimated 15 to 20 percent of prostheses used in the U.S. originate in foreign labs, and an even smaller percentage originates in China.
The American Dental Association is working with the federal regulatory agencies responsible for ensuring the safety of dental products to determine the specifics of the reported incident and whether it is an isolated case or indicative of a larger problem.
Here are some of the immediate steps the ADA is taking in light of this information:
We are informing all of our member dentists about the report.
We have contacted the appropriate federal authorities, including the Food and Drug Administration (Letter 1, Letter 2) and the Centers for Disease Control and Prevention (Letter 1, Letter 2).
We have begun our own investigation and will begin testing samples of dental crowns obtained randomly from U.S. and overseas laboratories in the next month.
We will communicate our findings to the public and the dental profession, as well as to the appropriate government agencies.
Lead should not be used as an ingredient in dental crowns. However, with sophisticated technology, it may be possible to detect lead in minute amounts in virtually everything, including water and air. With that in mind, the ADA’s test will investigate:
the degree to which lead may be present in dental crowns
where the lead may be located (i.e., in the metal alloy, the porcelain, the glaze, etc.)
The information the ADA gathers from our tests will be provided to dental professionals and the public. We will also share the information with the CDC and FDA and urge them to determine what effect, if any, there may be on human health.
Our investigation should not be viewed as a substitute for necessary oversight and enforcement by the federal and state government agencies responsible for protecting the public’s health and safety.
The ADA encourages patients to discuss any concerns about the safety of their dental crowns or other prosthetic devices with their dentists. The quality and the safety of dental materials you receive should matter most, more so than which dental laboratory produces the work.
How can you be assured of what you are getting? Here are some questions you can discuss with your dentist:
Do you produce your own crowns, bridges and other dental materials in the office or purchase them from a dental laboratory?
Where is the dental lab located?
Does the lab outsource crowns or bridges to a foreign country?
If the lab is in a foreign country, does it provide written documentation that it is registered with the FDA?
Does the lab provide written documentation that it uses FDA-approved materials?
Have you noticed any problems with the crowns, bridges or other items produced by this dental lab?
What other options do I have?
The ADA and its member dentists always place patients’ health and safety above all other concerns. We are committed to getting complete information on the extent of any problems with materials produced in dental labs as quickly as possible, and to sharing that information with the public as soon as it becomes available.
美国牙医用The Sickening News(令人做呕的事件)来形容此事件。比如由用I expect this health scandal will rock the world of dentistry(我想这健康丑闻将会摇动牙科医学的世界)等等，这些让人很不爽的言语来看待本次事件。
Chinese Dental Labs Turn Lead into Gold…?
When a 73-year-old Ohio woman fell ill, the news made national headlines. It wasn’t old age, or pneumonia, or cancer, or anything else you might expect. She had gotten lead poisoning from her new dental bridge.
Though she’d visited an American dentist, the bridge itself had been fabricated by a Chinese lab. Let me assure you that this is major news. I expect this health scandal will rock the world of dentistry.
The Ohio woman received this new dental bridge last year. However, the restoration site became inflamed, and chewing was unmanageably painful. The bridge was ultimately removed, and she’s had further surgeries since. She sent the bridge in question to a scientific testing laboratory, and its surface allegedly tested at 160 parts per million of lead. She has since retained a lawyer and is planning to sue her dentist. (Please note that she is planning to sue her dentist, not the dental lab!)
以上这段文章最后的部分很龌龊，我简单翻译一下:这位俄亥俄州女人去年安装了这个新的牙桥。 然而,，修复位置出现了炎症， 而且咀嚼难处理痛苦。并且她经过了有较进一步的手术后，牙桥最后被拆掉。 她将在问题的桥送到一间科学的测试实验室了，而且它的表面据说经过了多种测试。 她现在正授权一位律师正在计划控告她的牙科医生。 (请注意她正在计划控告她的牙科医生而不是牙齿的实验室!)
Chinese exports have received massive amounts of bad press after various health scandals. Do you remember the animals who died from eating tainted pet food? Then at least 21 Panamanians died after taking poison cough syrup. Danger made its way onto US shelves via toxic toothpaste. Most recently, children’s toys were pulled from the market after it was discovered that the paint contained high amounts of lead. All of these products were manufactured in China.
I know what many of you dentists are wondering: Is this for real? What evidence is there that Chinese labs are systematically producing lead-tainted dental restorations? Well, here’s the evidence that has so far come to light on this developing story:
The Ohio woman’s partial bridge apparently tested at 160 parts per million of lead.
Ohio TV station WBNS then conducted its own investigation, releasing the results on February 27. With the help of a local dentist, they ordered crowns from four different Chinese dental labs. One of the eight crowns tested positive for lead. The porcelain facing contained 210 parts per million.
The ADA announced that it had begun its own investigation, and had recommended that the FDA and CDC do the same. (Read the ADA’s response and their talking points for dentists.)
Though most press focuses on work manufactured in China, it’s worth noting that products are imported from many other countries, including India and Mexico. Imported restorations are dramatically less expensive than work produced domestically; in some cases, a crown from China may cost as much as 90% less. Cost-saving measures have led to more and more international manufacturing.
In the US, about 15-20% of dental lab work is produced in China (primarily bridges and crowns); that’s 7 million foreign crowns each year. Many of these products are distributed by American labs. Three years ago, less that 1% of UK dental restorations were produced in China; that number is now up to 5%.
Theoretically, the FDA monitors all dental products, whether produced domestically or abroad. The FDA has the authority to inspect any dental lab, foreign or domestic, that makes products sold in the US. Dental labs with overseas operations must register with the FDA. But within the US, only three states (Texas, Kentucky and South Carolina) require dental labs to register with state health departments.
The National Association of Dental Labs (NADL) officially recommended that the FDA close some of these legal loopholes. Needless to say, the organization that represents 1400 US dental labs has grave concerns about the allegations of tainted dental products.
The lead appears to be in the porcelain surface of some restorations. But many foreign labs use porcelain and other materials made in the US or Europe. So where does the lead come from? Many suspect the lead is in the glaze used to stain and seal the porcelain.Many pottery glazes contain lead. The lead itself is not particularly a problem until it comes into contact with acid. The acid is what allows the lead to leach out of the glaze. For pottery, this isn’t much of a problem. But since the human mouth is an acidic environment, lead might be transferred to the patient’s bloodstream.
Let’s be clear on this point: The FDA says there should not be detectable levels of lead in the surface material of a dental prosthetic device. Lead poisoning generally causes non-specific symptoms such as aches, abnormal bowels, or high blood pressure. As a result, proper diagnosis can take years.
Though labs are supposed to label outsourced work they provide to dentists, anecdotal evidence suggests that dentists do not in fact always know where their restorations were manufactured. Dentists: Do you know where your restorations are manufactured? Estimates suggest that 25% of US dentists are sending lab work to China - and what’s more, many of these dentists don’t even know it. You can’t just assume your dental lab does its own manufacturing. As a dentist, it’s your job to make sure you can stand behind the safety of any restorations you do.
Anyhow, folks, that’s just the tip of the iceberg! Check your inbox this Friday for a survey question on foreign dental labs. And you definitely won’t want to miss my next editorial. Do you know which of the major US dental labs import or manufacture foreign dental work? I do! And next week, I’ll start naming names.
鉴于本人的英文水准十分有限，暂不能将全问翻译。
