Detachable toothbrush bristles

  Most of us change our toothbrush when the bristles get damaged after lot of brushing. So here is the idea - in this toothbrush we can detach the old bristle head and attach a new bristle head to the stem of the toothbrush. When somebody want to market this here is how to do it--this whole case consits of toothbrush along with two or three detachable bristle head. So how is it? If it's already present before then somebody market it in India got a huge market for it.