A toothbrush having a handle portion and a neck portion connecting the handle portion with a head. The head has a brushing side and a rear side. The brushing side includes a plurality of bristle tufts for cleaning the teeth. The tufts are attachable in the head through tufting apertures, with each tufting aperture being assigned a blind-end hole having sidewalls and a bottom. The cross-sectional area of the head between a first bottom and the rear side differing from a cross-sectional area of the head between a second bottom and the rear side. The first bottom and the second bottom are arranged in the head in such a way that the minimum distance between the first bottom and the rear side as well as the minimum distance between the second bottom and the rear side are each in the range of between about 0.5 and about 2.5 mm.