A tooth may discolor after trauma, if the nerve dies, or even some time after a root canal treatment. It looks unsightly, especially if it is a front tooth.
The office of Dr. Sarkissian offers a procedure to bleach a tooth simultaneously externally and internally. During the procedure the chamber is opened to allow the bleach to be applied from the inside as well as the outside.
An unattractive tooth like this
Get more details about the procedure to whiten a discolored tooth elsewhere on this blog.