A cartridge for a ceramic matrix composite (CMC) seal segment of a segmented turbine shroud of a gas turbine engine is provided. The cartridge comprises a carrier segment and a CMC seal segment. A surface of the carrier segment and a surface of the CMC seal segment form a mating region proximate the entire perimeter of the CMC seal segment. The carrier segment surface may comprise a channel, and a compressible mating element may be disposed within the channel. Air may be supplied to a cavity, formed by the carrier and CMC seal segment, and the mating region.