Bicarbonate soda
It's cleans my oven along with white vinegar like new (and it was minging)
So I googled other uses for it and you can whiten and remove stains from teeth, so I decided to try it as I always get a stain on my bottom tooth (smoking and coffee) and I've tried everything to get it off inbetween dentist visits and ice just tried it and it's literally took the stain off in seconds!
Just thought I'd share the highlight of my night while everyone in here is in bed