A study has revealed that sealants and fillings used on children’s teeth may expose them to bisphenol A (BPA), says an article in the medical journal Pediatrics. The researchers say it is not yet clear whether this is hazardous to the long-term health of a child, as exposure does not generally last long. Dental sealants, which contain a variety of BPA derivatives are effective in preventing the majority of dental cavities in children and teenagers.

Researchers from The Children’s Hospital, Harvard Medical School, Departments of Pediatrics and Preventive Medicine, Mount Sinai School of Medicine, New York, and Columbia University College of Dental Medicine, New York set out to evaluate the BPA content of dental materials and find ways to manage BPA exposures.

The authors stress that dental materials present a far smaller and much less frequent exposure to BPA than other sources might, such as plastic food-storage containers, the linings of metal food cans, and some water bottles.

Reducing exposure to BPS is important for health, especially after prior research had discovered that BPA can pose health risks from its endocrine-disrupting, estrogen-like properties.
,br> The researchers learned, form a literature review, that BPA is released form dental resins through saliva enzymes. Up to 3 hours after resin placement, BPA can be detected in saliva.

We do not know how much of the BPA in the saliva is absorbed by the child’s body, the investigators say.

In a press release, the American Academy of Pediatrics writes:

Dental products that contain the bisphenol A derivative glycidyl dimethacrylate (bis-GMA) are less likely to be converted to BPA and have less estrogenic properties than those containing bisphenol A dimethacrylate (bis-DMA), and the authors suggest the more commonly used bis-GMA resins should be the preferred choice.

The authors say the important moment of BPA exposure for the child is during the placement of material in his/her mouth, and immediately afterwards.

The scientists suggest rubbing the material with pumice to remove the top liquefied layer of sealants. Saliva levels of BPA were also found to drop significantly if children rinsed their mouth for about 30 seconds after application of the sealant.

The authors believe that because of the substantial benefits the sealants provide, when weighed against the brief exposure to BPA, they should continue to be used in pediatric dentistry.

Manufacturers should be encouraged to develop materials with less estrogenic potential, the authors wrote. Whenever possible their use should be kept to a minimum during pregnancy, they added.

“Bisphenol A and Related Compounds in Dental Materials”
Abby F. Fleisch, MD, Perry E. Sheffield, MD, Courtney Chinn, DDS, MPH, Burton L. Edelstein, DDS, MPH, Philip J. Landrigan, MD, MSc
Published online September 6, 2010
PEDIATRICS (doi:10.1542/peds.2009-2693)

Written by Christian Nordqvist