Can a dentist notice cocaine use or marijuana smoking on your teeth?

Got in an argument with my friend the other day talking about this… anyways is it possible for a dentist to notice cocaine use by looking at your teeth? Or is it possible for them to know you smoke marijuana by looking at your teeth and how they rot maybe? I was thinking no but my friend insists they can so I just wanted to ask you all and see what the general consensus is. Thanks

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