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Complete mobility, preservation of viability, and adequate fixation during healing is essential to surgical repositioning of the maxilla to obtain a stable relationship with the mandible. LeForte I osteotomy techniques were used to connect various deformities of the maxilla in 15 adult patients.
In 1927, Martin Wassmund introduced a surgical procedure for moving the entire maxilla. The operation, which has since been called Le Forte I osteotomy or total maxillary osteotomy, was first used to correct an anterior open bite. The maxilla was not completely sectioned from its bony attachments, and no attempt was made to mobilize the maxilla at the time of surgery. Postoperatively, inermaillary elastic traction was used to close the open bite and stabilize the maxilla. In view of the state of art of anesthesia at the time, the lack of antibiotics and chemotherapeutics, and the empirical basis for maxillary surgery, this was truly a remarkable feat. Wassmund' s direct approach to the maxillary deformity was clearly years ahead of its time.
The design of the bony and soft tissue incisions have been continually modified to facilitate movement of the maxilla and to maintain circulation to the maxillary bone and teeth. Schuchardt and Kole devised a two-stage procedure to prevent impairment of the vascular supply to the maxilla. Postoperatively, Schuchardt used weights from an overhead traction device to reposition the maxilla forward. The second stage of his technique involved separation of the pterygoid processes from the maxillary tuberosities. Despite such measures, he became disenchanted with the procedure and concluded that the operation should not be used to treat patients with clefts. Axhausen used elastic traction after surgery to facilitate anterior movement and retention of a traumatically retrodisplaced maxilla. In an apparent attempt to circumvent these shortcomings, Gillies and Converse and Shapiro advocated advancing the maxilla by means of a transverse palatal cut of the 3unction of the palatine and maxillary bone. The success of this approach was not commented on. Bone grafting has been adocated to promote bony regeneration between the buccal bone cuts in the lateral portions of the maxilla. Obwegeser maintained that grafting the space between the posterior maxilla and the pterygoid plates was essential for stability.
Inability to move the maxilla the desired amount and relapse was common for the innovators of this operation. The surgeon' s fear that mobilization of the maxilla would devascularize and devitalize the bone and teeth was the dominant reason for such problems. The fear of traumatizing vascular structures, such as the greater palatine and internal maxillary arteries, was also a major objection to the technique.
Still, the biologic basis and surgical principles for maxillary osteotomies remained obscure and obviously contributed to postoperative devitalization and loss of bone and teeth. Microangiographic and histologic studies of total maxillary osteotomy performed in adult rhesus monkeys showed only transient vascular ischemia. Minimal osteonecrosis, and early osseous union when the maxilla was pedicled essentially only to the palatal mucosa. Preservation of the integrity of the greater palatine arteries was not essential to maintain circulation to the maxilla.
Fig l - Incisions of son time and bone for correction of maxillary retrusion by Le Forte I osteotomy techniqu