Do teeth whitening kits work?

Many options are available to achieve whiter teeth, and the safest among them comes in the form of teeth whitening kits provided by your dentist.

The first step in this popular take-home option involves making an impression of your teeth in the dental chair. Next, custom-fitting mouth trays will be manufactured for you and you will be provided with a professional-grade whitening gel to use in the trays. To achieve optimal results, you will be advised to wear the trays for several hours a day, or overnight each night, for two weeks.

The professional gel contains active ingredients, the most common ones being carbamide peroxide or hydrogen peroxide in concentrations of 10 to 16 per cent. The oxygen molecules produced by the active ingredients interact with the discoloured molecules in teeth, breaking the bonds that hold them together. The oxygen molecules then spread and the teeth begin to whiten. Results are consistent and in most cases will achieve a tooth colour five to seven shades whiter.

However, while teeth whitening kits can be very effective for many patients, they are not suitable for all. The gel is effective on natural tooth enamel only; hence, any dental restorations such as fillings, crown or veneers will not whiten using this treatment. Additionally, whitening gel is contraindicated for patients who are pregnant or breastfeeding, patients with allergies to peroxide and patients undergoing orthodontic treatment.

It is therefore recommended that patients interested in tooth whitening consult with their dental practitioner to select the safest and most effective way for them to achieve whiter teeth.


Iolanda Testa, BOH (La Trobe)
Dental Hygienist and Therapist