When you want whiter teeth, the dentist can shed light on that matter. Literally.
Light activation is a common sight for in-office teeth whitening, where the whitening agents react to any chemical light like halogen, LED, or plasma arc. These aren’t your ordinary desk lamps; agents such as hydrogen peroxide tend to react under different lighting conditions. The light helps the agent seep into the deeper layer of the enamel to cover up the tougher stains.
However, what really triggers the reaction is the heat from the light. One study cited that the role of light in the whitening process is to help the agent, now activated by heat, get as deep into the enamel as possible to commence whitening. With the exception of LED, these special lamps emit a lot of heat to trigger the intended reaction.
Then again, dentists are careful not to make thermal activation their goal in teeth whitening. Increasing heat output to boost the agent’s reactivity can also be harmful to the teeth. Thus, whitening systems that don’t emit heat, like LED lamps, are becoming popular among dentists. You may feel a bit of warmth or sting during a whitening operation but not any hotter than a fireplace.