Review (3/5): ouch :_(
as directed, i used the whitestrips twice a day.
i started on a saturday. at first it was tingly,
and didnt hurt much, i didnt even classify it as pain.
anyway on the third day, tuesday night, i noticed
i couldnt brush my upper gums anymore coz they hurt.
looking closer...they kinda darkened, or somehow
my gums sort of were swollen and a bit red, i cant describe it,
its not obvious from 3 feet away but looking really close
you will notice it.
it depends on your pain threshold. i never really thought of 'no pain no glory' until i tried this expensive thingy.