March 4, 2011
From Medical News Today:
Dentists need to take a closer look at potential hazards of exposing
patients to zinc, a common ingredient of many dental products, according
to a report by Amar Patel, DDS, resident and colleagues at the
University of Maryland Dental School in the March/April 2011 issue of
the journal General Dentistry.
all amounts of the element zinc are essential to the proper
functioning of nearly every body system, but too much can be toxic. Some
patients develop neurological problems from zinc. Toxicity from zinc
also can be manifested as nausea, stomachache,and mouth irritation.
The authors reviewed and analyzed a wide range of information
now available to dentists and physicians on the use of zinc in
dentistry. Many dental patients are regularly exposed to zinc from
certain restorative materials,mouthwashes, toothpastes and denture
“Dentists are suddenly hungry for more information on zinc,”
says co-author Nasir Bashirelahi, PhD, a professor with the School. “It
is used in dental products abundantly, especially denture adhesives or
Growing concern with denture adhesives may tip the decisions of
some patients away from getting fitted with dentures, which may require
perpetual pasting to the gums, to opting for dental implants instead,
typically a more expensive choice, says Bashirelahi.
In the paper “What Every Dentist Should Know About Zinc,” Patel
writes, “Of direct concern to dental professionals … has been the
recent discovery of neurologic disorders resulting from excessive use of
denture adhesives, having high leachable zinc contents which can cause
They explain that the link of excessive zinc intake has been
related to copper insufficiency due to the competition in absorption
patterns for the two metals in the gastrointestinal tract. Several
studies, according to the review paper, link copper deficient anemia
and neutropenia with an increase of zinc intake. (Neutropenia is a
blood disorder of abnormally low counts of neutrophils, important white
“Suddenly this issue is very important for the dental
profession, with many practical applications,” said Bashirelahi, who
knows of at least one manufacturer that has added a consumer warning
label on a product. And the authors also urge dentists to thoroughly
understand the relationship among zinc, health, and dental products
because of “legal ramifications.” Presently there are zinc-free
adhesives in the market.
Bashirelahi lectures in continuing education classes on
dentistry where the topic raises eyebrows. He says, “People are living
longer these days and want to stay healthy for as long as possible.”
Zinc plays an important role in human physiology. It is involved
in the proper functioning of the immune system, cellular growth, cell
division and normal cell death (a replacement system). The element also
plays a key patho-physiological role in major neurological disorders as
well as diabetes. Zinc deficiency is a worldwide problem, whereas excessive dietary intake of zinc is relatively rare.
Bashirelahi, a molecular endocrinologist, says that among the
principal roles of zinc is proper function of the pancreatic system.
Another zinc-dependent process is spermatogenesis, as zinc is important
for testosterone metabolism.