I had a white filing in a tooth many years ago, i am not sure what the official tooth is called but it is my first big tooth in my upper right arch. My dentist has told me that it has leaked and now i need root treatment (I am sure they talked about removing the root). I am okey with this, well as ok as anyone is about dental treatment. My issue is from a cosmetic perspective. Is there a cosmetic procedure that will keep my tooth white and looking the same as i have heard that a tooth can discolor after root treatment. is there anything else that i should be thinking about or asking about to keep my tooth as healthy and looking as well as can be?

Thanks