US Patent 9056178 Respiratory mask sealing interface

A sealing interface includes an inner cushion and an outer sheath. The outer sheath substantially seals against the facial contours of the user. The inner cushion and the outer sheath each have a nasal bridge region, left and right cheek regions and either one of an upper lip region or a chin region. In use these regions are aligned with the corresponding nasal bridge region, left and right cheek regions and either the upper lip region or the chin region of a user. The inner cushion includes a hinged region. The hinged region is adapted to flex substantially independently of the inner cushion cheek regions.