The invention relates to a tread comprising a plurality of relief elements (1) formed by at least one rubber mixture (base mixture). The inventive tread is characterised in that, seen as a section in a plane containing the thickness of the tread, at least one lateral face defining the element is at least partially covered by a second rubber mixture (covering mixture), said covering mixture part extending, when new, to a height Hr at least equal to 30 % of the height H of the face. At least one first base mixture ends on the contact face (2), when new, or at the latest after wear equal to a maximum of 10 % of the height Hr. According to the invention, the base mixture has a blacking rate higher than 2 ecp, and the covering mixture has a blacking rate higher than 0 ecp and at the most equal to 2 ecp.