Home| Preventative Dental | ...BPA Free Sealants |

BPA Free Dental Sealants

Do Sealants contain BPA, and are they actually worth it? Very little mention is ever made of preventative measures you can take to protect your teeth from dental decay. One of the few preventative things you can do is to have dental sealants.

Our natural protection is our enamel, which is one of the hardest substances in the body. If we visit a natural history museum you will see plenty of examples in nature of how effective the enamel is at protecting the tooth for hundreds and even thousands of years under a tremendous range of hostile environments.

Once the enamel is penetrated and the tooth bacteria begin to get to work, dental decay inevitably follows. One small cavity, when exposed three or four years later becomes deeper under the filing itself. The dental bacteria, s. mutans, is around 1 micron in size. By way of contrast the human hair is around 100 microns.

Dental sealants are a great preventative tool. The sealants are like a type of varnish applied with a brush to each tooth. They are usually only applied to the back teeth whose flatter surfaces are much more prone to plaque forming deposits. They form an effective seal which protects the enamel and will virtually ensure that the tooth is protected from decay.

The sealants are particularly useful for children. If the sealants are applied once they get their permanent teeth, and then re-applied in their teens, many young adults have reported reaching college without any fillings. Even if your child does not have the best diet in the world, and then has braces which make brushing and flossing a challenge, they can still get through with great dental health.

How much do Dental Sealants cost?

The sealants are relatively inexpensive. The cost is around $25-45 per tooth. So for eight teeth we are looking at between $200 and $360 which will give you great protection over five to ten years.

Sounds perfect no? As in everything in life, you have to do your research. There are several issues with dental sealants that you do need to be aware of.

Dental sealants don't seal the entire tooth, they are just applied to the top of the tooth. It is therefore possible to still need dental treatment on a tooth with a sealant. Sealants can also be unevenly applied or just may not last for very long. Particularly with children you never know what they are going to do.

You would not expect an industry that has decided to use toxic heavy metals mercury amalgam and fluoride to be over zealous about a little bit of plastic sealant in the mouth. And of course, it turns out they are not....

Sealants and BPA.

Some dental sealants release bisphenol A (BPA) which of course has stimulated high levels of public concern. Bisphenol A (BPA) is an endocrine disruptors, which mimic or alter the effects of hormones in the body, causing all sorts of problems for the body.

In 1996, the University of Granada in Spain performed the first report which showed detectable levels of bisphenol A (BPA) in the saliva of patients treated with dental sealants. As many of the sealants are used on children, the suggestion that a permanent source of BPA toxicity was actually in the mouth is a potential source of great concern. The dental sealants are going to degrade over time, and as they degrade with mastication they are going to release more BPA into the body. Dental sealants last about five-to ten years. Over time, especially with children biting and chewing they are going to be subject to wear and tear which will degrade the plastic coating.

More testing followed. A study supported by the ADA by Dr. Fung who is a professor of pharmacology at the University of Nebraska showed that low levels of BPA could be detected in the saliva in the hours immediately following the application of the dental sealant, but that no BPA could be detected in the bloodstream over time.

Why not just manufacture a BPA free sealant?
With the media warning over BPA, some manufacturers have been trying to position their dental sealants as "BPA" free. Many of the manufactures will state that there products do not contain any BPA for even trace BPA. For example, Ultradent, a dental sealant manufacturer states:

"When we put our guarantee in writing, we meant to leave absolutely no doubt. What we intended to convey was that: (1) We do not use Bisphenol-A as an ingredient in our dental sealant, (2) The Bis-GMA we use does not contain Bisphenol-A, and (3) Not only is Bisphenol-A not an ingredient in our product, there is not even a trace of the impurity found as a contaminant in our product."

The Americal Dental Association ADA in it's research on sealants says; " As a product of the degradation of the material in the oral cavity: Composite resins are formulated from a mixture of monomers that are commonly based on bisphenol A glycidyl methacrylate (bis-GMA). Some composite resins may contain other monomers, in addition to bis-GMA, that are added to modify the properties of the resin. An example is bisphenol A dimethacrylate (bis-DMA). Bis-DMA-containing materials can release very small quantities of BPA because bis-DMA is subject to degradation by salivary enzymes."

So now we are getting to the heart of the matter. Dental sealants are made from monomers that are derived from BPA, for example bis-GMA and bis-DMA. BPA by itself in rarely used in dental sealants. So when dentists say they have BPA free sealants, they do - until they begin to worn down by the saliva and mastication.

While the original sealants do not contain BPA, Bis-DMA is hydrolyzed to BPA by the saliva which will result in BPA being released from the sealants as they degrade over time.

It seems as if bisGMA based sealants are much more stable over time than Bis-DMA based structures. Make sure you select one of the bisGMA resins.

What is the risk?
So now we know that all the dental sealants will probably release some BPA over time. The sealants marketed as "BPA" free are not all BPA free over time. They will certainly degrade over time and the plastic will end up inside your body. This simply may be unacceptable to some people. However, this risk does need to put into perspective. The sealant is a very thin layer on a maximum of probably eight teeth. BPA is everywhere but particularly in the linings of processed food and in particular from canned foods, soda etc. Avoiding canned foods and sodas, and using BPA free water containers, as well as avoiding plastic packaged foods and microwave packaging will substantially cut your BPA exposure. By trying as best to eliminate the environmental BPA exposure, you will dramatically reduce the overall body burden of exposure to BPA from all sources and greatly minimize the additional exposure from sealants.

And the Conclusion Is?

Dental sealants present a very inexpensive and very effective protection from dental cavities. They are particularly good for children who won't always ensure that food deposits are removed from the flat surfaces of their teeth. Many children with a poor diet have still managed to avoid having dental cavities. Clearly, there are large benefits and dramatic cost savings. On the downside, the plastic sealant will degrade and will end up in your body. It's not the ideal solution, but when you weigh up the benefits of much better oral health for the small trade off it is on balance a trade off that is still very much worth doing.

Scientists are looking at BPA free alternatives. Interesting consumer choices made from BPA free materials are in active research. Until that time the choice is by no means perfect.

ADA positioning on dental sealants

Manufactures position on "BPA" free sealant.

Summary of the Granada BPA survey and safety background to BPA.

Dental Journal Summary of BPA