Do Fixodent Denture Adhesive Cautions Reflect Real-World Use?

Cincinatti, OHSuper PoliGrip manufacturer GlaxoSmithKline has decided to halt the production, distribution and marketing of its denture cream in view of current concerns over zinc poisoning. Meanwhile, the maker of Fixodent denture adhesive, Procter & Gamble, has elected to include a notation on its website with regard to the potential for zinc poisoning, but continues to sell the product.

Zinc is a fairly recent addition to denture creams, given the mineral's capacity to aid in adhesion, and is actually important to the human body in moderation. The ingestion of too much zinc, however, serves to deplete levels of copper in kind.

Various health issues, including mobility and neurological problems, have been traced to copper deficiencies and excesses of zinc in the body.

Zinc in denture creams has been found to be problematic, given the propensity for many denture wears to use far too much product in an effort to compensate for ill-fitting dentures. And while manufacturers are required to list ingredients on their products, the makers of denture creams are not required to reveal actual levels of zinc in their formulations.

Denture cream manufacturers note recommended amounts for regular use, but critics have cited the absence of any caution as to what can happen if a denture user applies too much in the real-world of denture adhesion where—more often than not—the popular myth is that more denture cream equates to a tighter fit.

At dentureliving.com, a product box at the lower right quadrant of the page about Fixodent Products includes a link for "questions about zinc." Clicking the link takes the viewer to a Q&A page that appears to focus on the minimal amounts of zinc users would ingest provided recommended amounts are adhered to, according to directions. Comparisons are made to levels of zinc "less than the amount of zinc in most daily multivitamins, less than six oysters (fried or raw), and comparable to six ounces of ground beef."

Under the header, "Is zinc harmful if swallowed," Procter & Gamble admits that Fixodent denture adhesive users may ingest a small amount of zinc, but then goes on to repeat the comparisons noted above.

A link invites users to peruse additional information from the Office of Dietary Supplements, which takes you to an exhaustive document most people would not likely read, let alone understand.

Returning to the main Q&A page, there does not appear to be any reference to the potential for harm due to zinc poisoning, or the potential risk involved in using more
Fixodent denture adhesive than recommended—in a manner and in amounts that many believe is the norm rather than the exception.

Few would argue that denture creams containing zinc are completely safe when used appropriately as directed. However, in the real world of dentures there are too many examples of ill-fitting dentures. Some Americans cannot afford to update or replace their denture when the structure of their mouths changes with age, producing a gradual and worsening problem with fit. For them, the answer is to use copious amounts of denture cream—quantities far exceeding recommended usage.

In February Super PoliGrip manufacturer GlaxoSmithKline halted sales of its product. Procter & Gamble is being urged to follow its rival's lead and pull denture creams containing zinc from the market.

In August 2008 the peer-reviewed journal Neurology reported on four patients suffering from neuropathy and other neurological symptoms typical of zinc poisoning and copper depletion. The article specifically linked excessive exposure to zinc in denture cream to "profound neurologic disease" in the patients reviewed.