The question of whether false teeth can be whitened is common for anyone with a dental prosthetic, such as a crown, veneer, filling, or denture. These items are known as dental restorations or prosthetics, and they are made from materials fundamentally different from natural tooth structure. Traditional chemical whitening methods, which rely on peroxide agents, are ineffective on these materials. The color of a prosthetic is permanent once it is created, meaning it cannot be lightened beyond its original shade.
Material Differences and Whitening Failure
Natural teeth have an outer layer of enamel, which is porous and allows the peroxide in whitening products to penetrate and break down stain molecules. Dental prosthetics are typically made from non-porous materials like porcelain, composite resin, or acrylic resin, which are designed to be color-stable and stain-resistant. Because these materials lack the porous structure of enamel, the chemical agents in whitening gels cannot penetrate them to initiate the color-changing oxidation process.
Applying commercial whitening kits will not change the intrinsic color of restorations. However, it may whiten surrounding natural teeth, creating a noticeable color mismatch. Strong peroxide concentrations can also have detrimental effects on the prosthetic materials themselves. For example, these chemicals can potentially weaken acrylic dentures or degrade the bond of composite fillings.
Using abrasive whitening toothpastes on porcelain or composite can also cause microscopic scratches on the surface glaze. This makes the restoration duller and more susceptible to future staining. Since prosthetics are chemically inert, the bleaching action simply does not occur.
Proper Daily Cleaning for Prosthetics
Since chemical whitening is not an option, maintaining the original color of prosthetics relies on diligent daily cleaning. The goal is to remove surface stains and plaque before they accumulate and dull the restoration’s shine. For fixed prosthetics, such as crowns and veneers, use a soft-bristled toothbrush and a non-abrasive toothpaste to clean the surfaces twice daily.
Pay special attention to the margin where the restoration meets the gum line, as plaque buildup here can lead to gum irritation and eventual discoloration of the surrounding natural tooth. Interdental brushes or floss threaders are particularly helpful for cleaning the tight spaces between teeth and under dental bridges. Water flossers are also effective for dislodging debris from around fixed appliances.
For removable prosthetics, like full or partial dentures, cleaning must be done outside the mouth. Brush these appliances daily using a denture-specific brush and a non-abrasive cleaner, such as a mild hand soap or specialized denture paste, never regular toothpaste. Dentures should be soaked in a commercial denture-cleaning solution or plain water overnight to keep the material hydrated and prevent warping.
Options for Correcting Existing Color Issues
When a prosthetic has become noticeably discolored, professional intervention is necessary. Professional cleaning and polishing by a dental hygienist can often remove extrinsic surface stains that have built up from coffee, tea, or tobacco use. This process uses specialized, low-abrasive pastes and tools that restore the original high-gloss finish without scratching the material.
If the discoloration is intrinsic, meaning the color has changed within the material itself or the original color match was poor, the only solution is replacement. Deeply absorbed stains in acrylic or a fundamental color mismatch in porcelain cannot be reversed. Replacing the restoration ensures a perfect color match to the rest of the patient’s dentition.
It is recommended that patients who plan to whiten their natural teeth and also need a new prosthetic should complete the whitening procedure first. Once the natural teeth have reached the desired lighter shade, the dentist can select the new crown, veneer, or filling color to match the brighter shade, ensuring a seamless and uniform smile. Composite bonding can sometimes be applied to the surface of a prosthetic as a temporary fix for minor color issues, but this is not a long-term solution.