Teeth can discolor for many reasons. Most everyone will experience a general discoloration of their teeth as they age. This is normal. And, there are many ways by which this situation can be remedied.
There can also be discoloration of only one tooth. This is much less common then the generalized discoloration but is still fairly common in its own right. This is typically due to trauma, with or without a root canal. A tooth that has suffered blunt force trauma may turn color.
The picture below is an example. This tooth suffered trauma and then needed a root canal. The tooth turned very dark and the patient wanted it changed.
The after picture is simply the temporary crown. The final crowns will look even better.
Dr. Jim Ellis, DDS
1220 33rd Street Suite C
Ogden, UT 84403