how do you get rid of a small bit discolouration on teeth?

my dentist scrapped off a layer, but can see the discolouration goes deep into the tooth. ive tried many whitening toothpastes and i know they dont work. how can i over it up?
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Depending on how deep the stain is, you might have to consider veneers that get cemented on the fronts of your teeth.
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