What causes dentures to turn white?

Dentures are custom-made prosthetic appliances to replace missing dentition. They are made by a dentist in conjunction with a dental laboratory and are made entirely of acrylic. Dentures are made to last. However, because they are made of acrylic they do need to be well cared for. Occasionally a person is seen with whitish gum tissue. There are several reasons a denture may turn white.

It used to be thought that dentures must be soaked in a cleaning solution all night to maintain hygiene and prevent the build-up of bacteria on the dentures. People soaked them in everything from salt water, to baking soda, to bleach. While the salt water and baking soda doesn't hurt the denture, the bleach most certainly does. It doesn't happen overnight, but chronic over-soaking of dentures in bleach water begins to bleach the pink out of the acrylic and makes the acrylic more porous, hence more susceptible to the growth of bacteria.

Thrush is oral candidiasis, or a yeast infection of the mouth. Thrush is usually caused by oral antibiotics that offset the good bacteria the body carries, allowing certain areas, such as the mouth to be overrun with bad bacteria. The result is a chunky white film that covers everything in the mouth -- the tongue, the roof of the mouth, even the denture itself. While it may look sinister and scary to someone who has never had it, or was not expecting it, thrush is easy to maintain with an oral antifungal the dentist or a medical doctor can prescribe. It also brushes or washes off of the denture without too much effort.

Brushing a denture is one thing, they should be brushed. However, they should be brushed with toothpaste, or simple soap and water. Some people are convinced that brushing their dentures with cleanser, like Comet or Ajax, is the way to clean dentures. Sure, it removes stain, but cleanser contains bleach, and bleach turns the acrylic on a denture white over time. Cleanser is also much too abrasive to be good for the denture. It breaks the shine on the teeth and the gums of the denture, giving it a sanded and matt look instead of a polished look.

For all the people who thought with dentures they would never have to clean their teeth again, here is food for thought, no pun intended. A denture, no matter how good it looks, is a foreign object in the mouth. Materia alba or plaque, that gooey, cheesy white substance that greets every mouth on waking, still builds up if not removed daily. It is unfortunate that people who lost their own teeth because of poor oral hygiene don't take any better care of their denture than they did their teeth. Dentures not cleaned for days at a time will develop a grungy white film of plaque that will soon harden and turn to tartar or calculus.