From 1979 to 1988, 30 osteomuscular or osteomyocutaneous free flaps of the iliac crest (revascularized by the deep circumflex pedicle) were used to reconstruct 28 mandibles severely compromised by radiotherapy exceeding 66 Grays. In addition to a perfect graft raising and microsurgical technique, perfect closure of the mucosal plane appears to be an essential factor of success. Over the years, this iliac crest flap appears to improve the radiological appearance of the bone stumps on either side. The procedure therefore appears to be particularly useful in the treatment of advanced radiation osteonecrosis.