DALLAS - Concern continues to mount over the safety of some denture adhesives used by millions.
After several years of News 8 investigations into denture paste poisoning, the maker of Super PoliGrip agreed last week to reformulate its product without zinc.
Zinc overload is suspected of causing serious and often permanent nerve damage in some denture cream users.
Meanwhile, News 8 has continued to hear from viewers frustrated they can't convince anyone to test them for the problem.
"When I lift my arms it's like somebody is pushing them back down, like they're heavy,” said Rachel King of her constant pain.
King was diagnosed with nerve damage, or neuropathy, but said doctors have been unable to determine a cause.
After seeing a 2009 News 8 report, King requested a zinc test. She has worn dentures and used denture adhesives that contain zinc for more than a decade. However, she said she was literally laughed out of her doctor's office when she made the request.
"I asked for the zinc test and she told me … it's ridiculous," King said. "[The doctor] said it was a waste of money and time to do the zinc test."
The same thing happened to Tammy Baugh, who has nerve damage so bad she can barely walk.
"[A nurse] said it couldn't be that, denture cream couldn't cause that," Baugh said of her recent visit to an emergency room where she explained the cause for her neuropathy.
Baugh said she assured the nurse that was the case. Tests have previously confirmed the presence of zinc in Baugh's bloodstream. She has joined a lawsuit against two major denture adhesive manufacturers.
"A lot of my clients were complaining of symptoms and go to their doctors and the doctors will simply ignore them," said attorney Andy Alonso. "They are unaware of the zinc poisoning issues. They are unaware that these products even contain zinc."
Alonso is a co-lead attorney on a lawsuit on behalf of dozens of denture adhesive users who say they've been poisoned.
Many people with poorly fitting dentures use excessive amounts of adhesive to make their false teeth fit better. Zinc is used as a bonding agent in some denture creams.
Zinc in denture cream can be absorbed through the gums or the stomach when swallowed.
Alonso said GlaxoSmithKline's decision to reformulate Super PoliGrip without zinc should convince doctors and patients that denture paste poisoning is real.
"If they're suffering these symptoms they need to take this information to their doctors, and frankly educate their doctors about what these products can do,” she said.
Fixodent, made by Procter & Gamble, also contains zinc, though in lower levels than Super PoliGrip.
Testing for zinc levels can be done through a relatively simple blood draw. That test eventually led to a diagnosis for Baugh's nerve damage.
"They've done every test imaginable and tests came back normal, normal until they did the zinc test,” she said.
King is hoping a doctor will agree to test now so she too can get answers for her worsening disability.