Many patients are interested in getting their teeth whitened. I believe it is my duty to inform and educate patients how teeth whitening works. Whitening procedure is most effective on stains accumulated exogenously, meaning stains from darker food, red wine, coffee, tea, tobacco products, etc. The type I use in my clinic is peroxide based methods which it literally 'strips off' dark stain layer from the tooth surface. It is extremely important that after the whitening procedures are completed, patients must stay away from the aforementioned dark staining sources for few days to prevent relapse of stain accumulations.