Thing is he's probably had other work done. When you whiten the teeth a lot of that other dental work won't whiten with it and it'll look kinda worse.
I had a filling on one of my top front teeth that partially came around to the front. The dentist carefully matched the filling to the color of my teeth, I can't notice it and I know where to look. I asked him about whitening and he said he'd have to redo the filling if I did because it wouldn't match anymore and would stick out like a sore thumb.
But yeah....JC could use a little less yellow

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