Tetracycline stain is very difficult to whiten. Almost impossible in my opinion. In a tooth that has been affected by tetracycline, it actually gets darker and darker the deeper you go into the "core" of the tooth. This is what is giving it the dark coloration. It's just too difficult for whitening agents to penetrate to the core of the tooth. Thus the treatment of choice for tetracycline affected teeth is usually to cover them with porcelain veneers.
Will Brite Smile Remove Tetracycline Stains?
Doctor Answers 2
BriteSmile - Not usually enough to satisfy
Britesmile alone likely won't do the trick. There may be SOME lightening of color, but the stains are all the way through the tooth so Britesmile won't have enough time to penetrate deeply enough.
Factors involved in whitening are frequency, duration, concentration of gel and time span of treatment. Single visit treatments are limited in this case.
There are some techniques that incorporate Britesmile as part of the process. However, I have found that the effects were not to the level desired by the patient or lasted long enough.
The best results have been with porcelain veneers, where one can choose how white they want to look.