A dilation device including a dilation instrument which includes a distal radially expandable section which is coupled via an elongate shank to a handling section, and an expandable covering with a closed distal end and an open proximal end, for the expansion section of the dilation instrument. The covering has a shank section extending along the shank of the dilation instrument. The open proximal end of the covering is detachably coupled to the distal end of the handling section of the dilation instrument. Furthermore, the covering is disclosed per se, which consists of a mesh material and has a shank section, which is connected to a coupling sleeve at the open proximal end.