UNMC College of Dentistry Researchers Determine Concern
of Human Health Risks of Dental Sealants Unfounded
Researchers at the University of Nebraska Medical Center College of
Dentistry have published results from a study that reassure dentists and
their patients that dental sealants are safe. The study appears in this
months issue of the Journal of the American Dental Association.
Sealants, made of plastic material, are highly effective in preventing
cavities and decay in adults and children. A fast and pain-free procedure,
sealants are often applied to the surfaces of back teeth in children —
the 6- and 12-year molars. Although sealants are more commonly used with
children, dentists also recommend sealants for their adult patients at
risk for tooth decay. The American Dental Association estimates about 20
percent of school-aged children have sealants on their teeth.
Several years ago concerns were raised among scientists after research
in mice suggested bisphenol A — a chemical used in sealants and other
plastic products — may pose a health hazard to humans. The chemical is
said to mimic estrogen, the female hormone. Estrogen has been associated
with causing cancer.
According to the American Dental Association, the studies in question
had not looked at dental sealants nor if the chemical was absorbed in humans.
Through subsequent national studies, researchers have found no proof that
the chemical poses a health risk for humans.
Eric Fung, Ph.D., a pharmacologist at the UNMC College of Dentistry,
was the principal investigator of a $50,000, one-year study which was funded
with a grant from the American Dental Association Health Foundation. Dr.
Fungs study is believed to be the first to see if bisphenol A is present
in the saliva and blood of patients and at what levels.
The study, which used a common sealant, also measured how much of the
chemical was released at various time intervals.
The study looked at 40 adults age 20 and older who had never had sealants
placed on their teeth. Dentists placed sealant on one to four teeth to
see if the bisphenol A would be absorbed into the bloodstream where it
could circulate in the rest of the body, posing a potential health risk.
Saliva and blood was collected and tested in the study participants
immediately before sealant placement and at one hour, three hours, one
day, three days and five days after sealant placement. Although the chemical
was detected in some saliva samples from one to three hours after the sealant
was placed then disappeared, the study showed that bisphenol A was not
absorbed in the bloodstream or if present, it was so low that it was not
detectable.
This study tells us sealants are safe and the concern about bisphenol
A is unfounded, Dr. Fung said.
UNMC College of Dentistry faculty members, Henry St. Germain, Jr., D.M.D.,
M.S.D. and Nels Ewoldsen, D.D.S., served as co-investigators of this study.
A summary of the research can be found at www.ada.org under ADA Publishing
Co., Inc.
The UNMC College of Dentistry, which celebrated its 100th anniversary
last , serves Nebraskans and states that have no dental schools, including
Kansas, South Dakota, North Dakota and Wyoming. For five of the last six
years, the colleges freshman class has ranked first among the 55 U.S.
dental schools for incoming grade-point average. The college offers programs
in doctor of dental surgery (D.D.S.), bachelors degree in dental hygiene,
certificate in dental hygiene, a general practice residency program and
post-graduate specialty programs in endodontics, orthodontics, periodontics,
pediatric dentistry and prosthodontics.
UNMC is the only public academic health science center in the state.
Through its commitment to research, education, outreach and patient care,
UNMC has established itself as one of the country’s leading centers for
cancer research and treatment, solid organ transplantation and arthritis.
Nearly $32 million in research grants and contracts were awarded to UNMC
scientists during the past fiscal year. In addition, UNMCs educational
programs are responsible for training more health professionals practicing
in Nebraska than any other institution.