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Midface bone lengthening was performed on three young, adult sheep using distraction osteogenesis following osteotomy of the maxilla and mounting of an extraoral fixation device. The midface was gradually distracted, 2 mm/day, for 21 days, up to approximately 40 mm. A marked midface advancement was noted. Following a further 6 weeks of retention, the device was removed and the animals were followed for 1 year. Biopsies specimens were taken from the distracted area at the end of the distraction period, after the additional 6 weeks of retention, and finally 1 year later. A nondistracted area of the maxillary bone served as control. The specimens were analyzed histologically, histochemically, and by scanning electron microscopy for the ultrastructural pattern, mineralization, mineral content, and approximate Ca2+ concentration. Clinically and radiographically, all sheep fully bridged the experimental gap. Histologically, at the completion of distraction, collagen bundles and slender bone trabeculae oriented in the direction of the distraction could be seen. At the end of the retention period, the trabeculae thickened noticeably and were partially replaced by mature lamellar bone. At the end of 1 year and after completion of the process of remodeling, the pattern of the distracted area resembled the control area. The mineralization, as reflected by quantitative calcium analysis, compared with the nondistracted area, demonstrated a low rate of mineralization after 3 weeks of lengthening, increased 6 weeks later, and after 1 year became nearly the same as in the nondistracted area. In conclusion, distraction osteogenesis provides satisfactory quantitative and structural new bone.

Reconstruction of large maxillary defects has been a long-standing challenge to the reconstructive surgeon. Total maxillary reconstruction is desirable but often not possible; ideally, this would provide all the anatomical structural support, function, and esthetics missing because of the defect. A case is presented in which all the criteria for total maxillary reconstruction have been fulfilled. The patient is a 60-year-old man who had wide excision of his maxilla for ameloblastoma, followed by temporal bone flap reconstruction, which failed. He presented to our institution for further evaluation and possible treatment options; these were discussed with the patient and the multidisciplinary team that deals with congenital and acquired deformities in the head and neck area. An iliac crest free flap that included the inner table of the ilium based on the deep circumflex iliac artery was used for the reconstruction. The procedure is described, including restoration of a nasal lining. Osseointegrated implants were used for dental rehabilitation. Ameloblastoma is briefly discussed. The goals of maxillary rehabilitation and obstacles to obtaining those goals are presented. Options available for maxillary reconstruction are discussed, along with some of their advantages and disadvantages, as is the reason why the iliac crest free flap with the inner table of the ilium was chosen. An iliac crest free flap with microvascular anastomosis to facial vessels was used to reconstruct a large maxillary defect. Osseointegrated implants were used to facilitate dental rehabilitation. Our patient has excellent restoration of oronasal function with a satisfactory esthetic result.

Children who receive radiation for malignant tumors in the orbital area frequently develop widespread craniofacial deformities. These affect the skull, orbit, maxilla, and mandible. When these patients seek treatment at a later age, they require careful assessment using cephalometrics and three-dimensional imaging. It is recommended that the four levels of skeletal deformity be corrected in a single procedure, that is frontotemporal expansion with repositioning of the skull base area, orbital expansion and repositioning together with maxillary and mandibular surgery. Bone grafts should be inlay rather than onlay and soft tissue should be supplied by free-tissue transfer. This counteracts any residual ischemia related to the previous radiation therapy. The second surgical stage is designed to reconstruct the socket and the eyelids to allow more satisfactory rehabilitation with an ocular prosthesis. In patients who have a globe present, the usual enophthalmos can be corrected by repositioning of the eye as part of the first procedure by reducing the anteroposterior dimensions of the socket. In bilateral cases, the deformity is hourglass in nature and requires correction in the frontal and temporal area with lateral displacement of the orbits. A bimaxillary procedure is also indicated. It is emphasized that to formulate a satisfactory operative plan an in-depth three-dimensional analysis of the deformity is mandatory.