If the stains have come in after ur teeth erupted, mostly they are deposits which have attached themselves on the tooth surface. Such stains called extrinsic (or outside) stains can be removed by scaling and polishing at the dental clinic. In case you have a developmental problem of the tooth (stains from inside or intrinsic), then depending on how severe is the discoloration, composite fillings or laminates or crown will be suggested.

ascertain the reason first with help of your dentist meanwhile normal scaling and polishing recomended