Cavity filling and dental teeth cleaning before or after Crest Whitening Strips?

I dont know what I should do first.
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The cleaning should be done first. This will remove the plaque and stain and the strips will work better. Then see how white you can get them with the strips. Then do the fillings. You can then match the color to your hopefully whiter teeth. Remember that you cannot make the filling material lighter with bleaching or strips. So if you place the fillings and the lighten the teeth, the fillings will be darker and stand out.
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