A method of making a self-sealing patch for a tissue expander implant includes providing a first sheet having a first sheet outer perimeter and a first sheet inner edge defining a first central opening, providing a second sheet having a second sheet outer perimeter and a second sheet inner edge defining a second central opening, aligning the first and second sheet outer perimeters and the first and second sheet inner edges, capturing an outer washer between the first and second sheet outer perimeters for attaching the first and second sheets together, and capturing an inner washer between the first and second sheet inner edges for attaching the first and second sheets together. The method includes spacing an inner perimeter of the outer washer from an outer perimeter of the inner washer to form a sealed annular space between the attached first and second sheets, and disposing a hydrophobic material within the sealed annular space.