Why are teeth dificult to whiten?!
Question:
Why are teeth dificult to whiten?
Answers:
It depends on where the stain is coming from. Stain from the inside of the tooth can be whitened, but can take a lot more work and time.
Stain on the outside of the tooth is easier to remove, but can still be a little persistent. Get a cleaning first, and it'll be a little easier.