CHAPEL HILL - Mercury exposure from dental amalgam fillings poses no threat to children's health, according to a new study by researchers at the University of North Carolina at Chapel Hill School of Dentistry.
Environmental exposure to mercury was low in the North Carolina children studied, the scientists said, and they could detect no additional exposure to mercury from dental work done to primary teeth, also known as baby teeth.
A report on the findings appears in the current issue of Pediatric Dentistry. Authors are Drs. Diane Dilley, associate professor of pediatric dentistry, and James W. Bawden, Alumni Distinguished professor and former dean of dentistry, both at UNC-CH.
"We compared primary teeth from children who had had fillings with primary teeth from children without fillings," Dilley said. "We did find tiny amounts of mercury in the teeth we examined, but statistical analysis showed no correlation between the number of fillings and the amount of mercury present.
"In other words, the children we studied not only got very little mercury from their environment, they also got none we could detect from the fillings," she said. "They were safe from mercury exposure."
Mercury contained in dental fillings has been a concern to a small percentage of people over the past several decades because mercury can have devastating effects at higher concentrations in the body, she said. Overexposure to environmental mercury through industrial waste water, for example, caused severe nerve damage and mental retardation among children living near Minamata Bay, Japan, in the mid-1950s.
With no scientific evidence to support their claims, however, some people have said mercury fillings caused multiple sclerosis and numerous other maladies, Dilley said.
Comparisons of primary teeth excavated from beneath a 12th-century
Norwegian church with primary teeth collected from Norwegian child
Contact: David Williamson
University of North Carolina at Chapel Hill