In the inventive method, a tooth whitener having a concentration of hydrogen peroxide significantly lower than the concentration typically used in in-office applications is applied to the teeth in gel form. Next, thin transparent film is placed over the teeth to seal the tooth whitener onto the teeth. The film creates a closed system that precludes oxygen from migrating away from the teeth into the atmosphere. A white light in the range of 380-660 nm wavelength is then activated to assist in exciting oxygen in the path of the light and the oxygen molecules bombard the tooth surfaces. The oxygen molecules may not easily escape from the tooth surfaces into the atmosphere due to the wrap and, thus, their whitening "power" is enhanced and lengthened. Then, the patient may stabilize the whitening results over a 7 to 10 day regime using a lower concentration tooth whitener.