Colour of tooth as we see them, depends from 2 factors.

First is color of dentin. You get your colour of dentin by genetics mixed with your habits and habits of your guardians when you were a kid. And that colour is more important for colour of your teeth... Dentin color you corect by bleaching with carbamideperoxide or hydrogenperoxide, either with home bleachin trays or by inoffice bleaching... You can think of this like an inner colour of tooth.

Over dentin comes enamel. Enamel is in its nature transparent so it has a little impact on tooth colour unless it is damaged or ill produced and stained during its development... The problem of that you corect by abrassion, or by removal of it and replacing it with some material like ceramics or composites... I don`t think that abrassion with any abrasive tooht paste or a charcoal is needed to correct your tooth color... With abrasion of enamel you lose its properties and make your dentin exposed etc...

Second factor is dental plaque. It forms over a dentin and it gives a outer colour of a tooh. But if you ignore it for a long time (poor oral hygine) it can transfer pigments trough enamel to dentin and make dentin darker... Simply oral hygine and correct tooth cleaning with a standard medium toothbrush and standard tooth paste, are enough to clean tooth and get rid of plaque... And if you want to be sure you cleand them well you can get profesional cleaning once in a six monts... If you don`t want that you can simply eat more apples and they will do the job, but if dental calculus ocurs then you must visit your dentist to remove it for you...

So my point is this... don`t destroy your enamel by abrassion, simply removal of dental plaque and its color will make your teeth whiter, and if it is not enough have your teeth bleached and corect dentin colour...

And by the way main enemies of your withe teeth are: smokes (all kind), coffee, tea - sage most of all, cola, red wine, and dark marmelades... Simple toothbrush and paste cleaning will help with coffee and rest of foods and drinks, but smoke stains must be bleached but only when you stop smoking...