Denture Adhesives with Zinc may cause neurological damage with excessive use
The British drug company GlaxoSmithKline announced Thursday the intention to transition from zinc in denture adhesives to zinc- free denture adhesives. This move is in response to hundreds of consumer reports to the company that zinc in the creams are causing neurological damage as well as other problems due to excessive long term use of the denture adhesives, writes ABCNews.
Twenty years ago, the US FDA approved use of zinc-based adhesives in denture creams, stating that the creams are safe when used as directed. Federal health experts state that the daily recommended dose of zinc for females is 8 milligrams per day and for males it is 11 milligrams per day. Zinc is an essential mineral for the body, protecting it from illness, repairing muscle and rebuilding and regenerating cells. When there is too much zinc, it causes a problem in the absorption of copper, resulting in neurological damage, and sometimes paralysis.
The denture cream Poligrip contains 38 milligrams of zinc. However, when the cream is used as directed there is no need for concern. One tube of the adhesive is meant to last from 8 to 10 weeks. However, some consumers will actually use between one to two tubes per week. This yields an overdose of 45 times the daily recommended dose of zinc.
Reuter’s states the company Proctor and Gamble have no intentions of changing their product Fixodent. P&G’s spokeswoman Michelle Vaeth told Reuter’s that “the levels of zinc in Fixodent are half that used in Super Poligrip. Fixodent formulations have been safely marketed for 20 years.” However, GlaxoSmithKline is not the only company involved in the denture adhesive lawsuits. P&G have been implicated for the same reasons. The problem lies not in the fact that the creams have been safely marketed, but that the consumer may not use the denture adhesive as directed. If the consumer uses excessive amounts of cream, then excessive long term use can cause a toxicity of zinc.
GlaxoSmithKline has stated that current creams will not be taken off the shelf because if the consumer reads the directions and follows them, the cream is safe to use. However, as a precautionary measure, the British drug company is transitioning to all zinc-free products. The company already has several zinc-free products on the shelf. These include Super Poligrip Free, Super Poligrip Comfort Seal Strips, and Super Poligrip Powder. The products being replaced are Super Poligrip Original, UltraFresh and Extra Care. New packaging will state “Zinc-Free”.
A 2008 Neurological study has prompted the litigations stating that excessive use of dental adhesives with zinc may cause neurological symptoms including loss of balance, loss of sensation in the hands and feet, and possible paralysis. The buildup of excessive zinc over a period of time is what causes the neurological symptoms. However, the American Dental Association stated in 2009 that it had not found any neurological symptoms linked to the normal use of dental creams. For those who use much more than directed, the Association said these are the patients who have loose-fitting dentures. They are recommended to go to their dentists to get their dentures adjusted, writes the Wall Street Journal. The American Dental Association has also noted that the FDA has not taken any action regarding the use of denture creams. Currently, denture creams are considered to be a Class I medical device which is considered to be little or no risk.