Dentin is the layer of a tooth that lies just below the outer covering of enamel. It is darker in color so that when the enamel begins to deteriorate the dentin will show through. This type of staining is referred to as intrinsic, meaning that it is unfortunately, a natural phenomenon.
A whitening toothpaste or mouthwash won’t work to remove an intrinsic stain, it will require a bleaching system or in more extreme cases, a professional restorative procedure such as bonding or capping.
Extrinsic stains are easier to remove, an over the counter toothpaste will usually do the job. The stains are caused by the coloring agents in the foods and drinks that we put into our mouths. Think of it this way – anything that can leave a stain on your napkin when you wipe your mouth after eating it will have the same affect on your tooth enamel. If you do choose to whiten your teeth however, avoid any stain producing food or drinks for the next few days after the treatment.
Before you try to get rid of those unsightly stains on your own, see your dentist. He will be able to evaluate and determine the source of the discoloration and advise you how best to proceed.