Teeth whitening scores black marks
27 February 2009
Having your teeth bleached with the assistance of optical radiation (bleaching lamps) to get a pearly white smile may be damaging your eyes, your skin and your wallet.
British researchers have investigated the effectiveness of 7 bleaching products with and without the simultaneous use of bleaching lamps. They found adding the UV lamps to the initial treatment made no difference to the efficacy of the bleaching (Photochem Photobiol Sci 2009, online).
Previous claims that the light-assisted bleaching was more efficient than ordinary bleaching had not been substantiated in the literature, the study authors said. They found ‘a lack of additional whitening effect when light is used compared to bleaching without light’.
More worryingly, the researchers found evidence that many lamps were exceeding international guidelines on optical radiation exposure time and threshold limit. They said the lamps were potentially as damaging to skin and eyes as sunbathing on a summer afternoon.
Using extracted human teeth, the researchers determined the bleaching effect immediately after treatment and again one week later. At the inspection one week later, there was no difference in bleaching between ordinary and light-assisted treatments.
Last Reviewed: 27 February 2009
- 1. Photochem Photobiol Sci 2009, online
