William Atkins
Friday, 30 January 2009 20:50
Science -
Health
Page 2 of 3
The researchers analyzed seven different commercially available bleaching products with respect to their ability to whiten human teeth, either with or without the use of seven different bleaching lamps.
They then determined the effectiveness and the safety of the bleaching effect immediately after the treatment and one week later.
The researchers used a scanning electron microscope to search for any adverse problems resulting from the treatments.
They stated,
“International guidelines on optical radiation were used to assess eye and skin exposure hazards due to UV [ultraviolet] a
nd visible light emission from the lamps.”
They found that:
“Inspection of teeth one week after bleaching showed no difference in efficacy between teeth bleached with or without irradiation for any of the products. Scratches, probably from the cleaning procedure were frequently seen on bleached enamel irrespective of irradiation.”
In addition, “
Maximum permissible exposure time … and threshold limit values were exceeded for about half the bleaching lamps investigated. One lamp exceeded [maximum permissible exposure time]
even for reflected blue light within the treatment time. This lamp also exceeded [maximum permissible exposure time]
values for UV exposure.”
Specifically, the researchers found that the lamps do not help to make the teeth whiter when compared to just using bleach (hydrogen peroxide); that is, the UV rays do not “activate” the oxidation process of the bleaching.
However, they also found that the UV lamps damages skin and eyes up to
“four times as much as sunbathing for an entire afternoon.” [Gizmag: “
UV tooth bleaching ineffective and dangerous”]
What did the researchers state with respect to damage to teeth and bleaching? Read page three.
