is there any safe whitening method or procedure that can whiten the crowning tooth as well?

i have one in front.i am afraid that after do the whitening the colour will differ from one another after some time...
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The porcelain crown is color stable and there is no whitening that can be done on it. If you have all of your teeth bleached and it appears darker than the rest, the only way to correct the situation is to re make the crown.
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