Dentures are removable prosthetic devices that must be kept moist when not in use. They are designed to function within the consistently wet environment of the mouth. Proper storage is necessary for maintaining the appliance’s structural integrity and preventing health issues.
Why Dentures Require Constant Hydration
Most dentures are fabricated from polymethyl methacrylate (PMMA), a type of acrylic resin. This acrylic is inherently porous and designed to absorb moisture, a characteristic known as water sorption. This absorbed water acts as a plasticizer, keeping the material pliable and flexible.
This pliability helps the denture maintain the precise, custom shape required for a comfortable and secure fit against oral tissues. The material is dimensionally stable only when it remains consistently hydrated. While saliva provides this necessary moisture when the denture is worn, an alternative source of hydration is required when removed to prevent structural changes.
Consequences of Letting Dentures Dry Out
Failing to keep the acrylic material hydrated can lead to warping, which is a change in the denture’s original shape. This occurs because the loss of moisture happens unevenly across the surface, causing the material to shrink and distort. Even a slight deviation from the custom fit can cause the denture to slip, rub against the gums, and become uncomfortable.
As the moisture evaporates, the acrylic becomes stiff and brittle, increasing the risk of physical damage. A dry denture is susceptible to cracking or splitting if accidentally dropped or subjected to stress during cleaning. Furthermore, the porous surface promotes the colonization of microorganisms, most notably the fungus Candida albicans. This microbial buildup, or biofilm, can lead to infections such as denture stomatitis, causing inflammation and irritation of the oral tissues.
Proper Solutions for Overnight Storage
The goal of overnight storage is to maintain hydration and ensure cleanliness. The most basic option is clean, room-temperature water, which is sufficient to prevent the acrylic from drying out and warping. However, water alone does not provide antimicrobial benefits and may allow for bacterial growth.
A better option is to use a dedicated denture cleaning solution, often effervescent tablets dissolved in water. These solutions contain ingredients like alkaline peroxide, formulated to penetrate and break down the biofilm while eliminating harmful microorganisms and odors. Follow the product’s instructions, as soaking for too long can weaken the denture’s structure.
Never use boiling or hot water for soaking or cleaning, as the high temperature can cause immediate and permanent warping of the acrylic material. Avoid using abrasive household cleaners, bleach, or regular toothpaste, which can scratch the denture’s surface, creating microscopic grooves where plaque and bacteria can accumulate. Bleach should be used with caution and only if recommended by a dental professional, as it can weaken the acrylic or corrode any metal components.