Good Evening I was would like to ask you for your expert advice, my Sister and I would like to have our teeth whitened but are really confused. We had it done professionally a couple of years ago by our dentist.For which we paid £500 each, but when we went home we ate a banana roll as we’re vegan and we didn’t know or think that the colour of the food would affect our teeth but, we later found out by reading about it online that it would. I would allso like to point out that  we also didn’t continue with any home whitening kits as we weren’t told to. Can we just buy the home whitening kits? Or do we need them whitened by a dentist first? Thanks