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The researchers wrote about how their
powder works. It is activated by electric toothbrush
, which create a small electric field over the teeth. This causes a reaction known as "reactive oxygen
". These are compounds that break down stain-causing
. The researchers said their laboratory
were very promising. They tested human teeth that were
discoloured with tea and coffee. After four hours of
, there was
whitening. After 12 hours of cleaning, the teeth were 50 per cent whiter than those brushed with
. The researchers said the next
is to incorporate the powder into a toothpaste formula.