What to Look For in a Teeth Whitening Kit
A teeth whitening kit typically contains an applicator, such as a strip or tray, which is used to apply the bleaching agent, usually hydrogen peroxide, directly to your teeth. It then processes over time to whiten the enamel.
Many over-the-counter whitening kits contain high levels of hydrogen peroxide, which can cause tooth and gum sensitivity, so it’s important to read labels and follow instructions carefully. Some whitening gels are placed into pre-filled or moldable trays, while others can be applied with a thin plastic strip that sticks to your teeth. Whitening strips may be easier to use than trays, but they don’t stay in place as well.
Choosing the Right Teeth Whitening Kit for a Brighter Smile
In addition to the active whitening ingredients, look for a list of other ingredients that can help prevent or treat mild side effects, such as potassium nitrate (for sensitivity), fluoride and xylitol (both for healthy teeth), and benzocaine to numb the lips and gums, says Jaylyn Pruitt, a consumer editor at beauty lab BeautyLab. Also look for a kit that has been tested by a dental association, which may indicate a higher level of safety.
Most dentists we spoke to agree that whitening kits are safe for most people, but those with dental issues such as cavities or gum disease should visit a dentist before using them. They also should not be used to lighten crowns, fillings or other restorations, warns Dr. Rubinshtein. And some whitening ingredients can wear away the outer layer of the enamel, leaving your teeth more vulnerable to staining in the future.