Textile seal-forming structure with multiple curvatures

A cushion assembly for delivery of a flow of air at a continuously positive pressure with respect to ambient air pressure to an entrance to a patient's nares and to an entrance to the patient's mouth, the cushion assembly comprising:

• a plenum chamber at least partially forming a cavity pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber including at least one plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by the patient;
• and
• a seal-forming structure comprising a silicone support structure and a textile membrane, the textile membrane being constructed and arranged to, in use, form a seal with the patient's face, the textile membrane comprising:
• a nasal portion configured to, in use, form a seal with an underside of the patient's nose, the nasal portion including two naris openings and a bridge portion positioned between the naris openings, the two naris openings being arranged to deliver the flow of air to the entrance to the patient's nares in use, and
• an oral portion configured to, in use, form a seal with a region of the patient's face around the entrance to the patient's mouth, the oral portion including an oral portion hole formed therein such that the oral portion encircles the oral portion hole, the oral portion hole being arranged to deliver the flow of air to the entrance to the patient's mouth in use,
• wherein the textile membrane includes a textile material configured to contact the patient's face in use, the textile material being a single, continuous piece of material,
• wherein the textile membrane is connected to the support structure at an overlapping region, the textile membrane being connected directly to the support structure to form a layered arrangement in the overlapping region with no additional layers between the textile membrane and the support structure,
• wherein at least the nasal portion of the textile membrane extends radially inwardly beyond the support structure, the nasal portion of the textile membrane being configured to press against the patient's face in use such that the patient's nose is not received in the cavity, and
• wherein the nasal portion of the textile membrane includes a three-dimensional shape having multiple curvatures.