Tooth Whitening - How safe is it?

For more than a decade, the ADA Council on Scientific Affairs has monitored the development and the increasing numbers of whitening oral hygiene products. As the market for these products grew, the Association recognized a need for uniform definitions when discussing whiteners.

For example, "whitening" is any process that will make teeth appear whiter. This can be achieved in two ways. A product can bleach the tooth, which means that it actually changes the natural tooth color. Bleaching products contain peroxide(s) that help remove deep (intrinsic) and surface (extrinsic) stains. By contrast, non-bleaching whitening products contain agents that work by physical or chemical action to help remove surface stains only.

Whitening products may be administered by dentists in the dental office, dispensed by dentists for home-use, or purchased over-the-counter (OTC), and can be categorized into two major groups:

• Peroxide-containing whiteners or bleaching agents; and
• Whitening toothpastes (dentifrices)

Peroxide-containing whiteners or bleaching agents

Dentist-dispensed and OTC home-use products
Dentist dispensed and OTC home-use tooth whitening bleaches are eligible for the ADA Seal of Acceptance. The products in this category that currently bear the ADA Seal contain 10 percent carbamide peroxide; however, participation in the program is not limited to products of this concentration or type of bleach. There are many whitening options currently available to consumers both from the dentist as well as from retail outlets.

In a water-based solution, carbamide peroxide breaks down into hydrogen peroxide and urea, with hydrogen peroxide being the active bleaching agent. Other ingredients of peroxide-containing tooth whiteners may include glycerin, carbopol, sodium hydroxide and flavoring agents.

Accumulated clinical data on neutral pH, 10 percent carbamide peroxide continue to support both the safety and effectiveness of this kind of tooth-whitening agent. The most commonly observed side effects to hydrogen or carbamide peroxide are tooth sensitivity and occasional irritation of the soft tissues in the mouth (oral mucosa), particularly the gums. Tooth sensitivity often occurs during early stages of bleaching treatment. Tissue irritation, in most cases, results from an ill-fitting tray rather than the tooth-bleaching agents. Both of these conditions usually are temporary and stop after the treatment.

Professionally applied bleach whiteners
There are many professionally applied tooth whitening bleach products. These products use hydrogen peroxide in concentrations ranging from 15 percent to 35 percent and are sometimes used together with a light or laser, which the companies state accelerate or activate the whitening process. Prior to application of professional products, gum tissues are isolated either with a rubber dam or a protective gel. Whereas home-use products are intended for use over a two-to-four week period, the professional procedure is usually completed in about one hour.

As with the 10 percent home-use carbamide peroxide bleach products, the most commonly observed side effects of professionally applied hydrogen peroxide products are temporary tooth sensitivity and occasional irritation of oral tissues.

Whitening toothpastes

Whitening toothpastes (dentifrices) in the ADA Seal of Acceptance program contain polishing or chemical agents, rather than bleaches, to improve tooth appearance by removing surface stains. They do this through gentle polishing, chemical chelation, or some other non-bleaching action. Several whitening toothpastes that are available OTC have received the ADA Seal of Acceptance.

Link:

ADA (American Dental Association): http://www.ada.org/prof/resources/positions/statements/whiten2.asp