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This study examines the short-term stability of bimaxillary surgery following Le Fort I impaction with simultaneous bilateral sagittal split osteotomies and mandibular advancement using two standard techniques of postsurgical fixation. Fifteen adults had skeletal plus dental maxillomandibular fixation, and fifteen adults had rigid internal fixation using bone plates in the maxilla and bicortical bone screws between the proximal and distal segments in the mandible. The group with rigid internal fixation did not undergo maxillomandibular fixation. Radiographic cephalograms were analyzed during the postsurgical period to evaluate skeletal and dental stability. There was no statistical difference in postsurgical stability with rigid internal fixation or skeletal plus dental maxillomandibular fixation other than the vertical position of the maxillary molar; the skeletal plus dental maxillomandibular fixation group had a significant amount of postsurgical intrusion of the maxillary molar when compared with the rigid internal fixation group. Although the other measures showed no statistically significant difference between the experimental groups, the amount of variability in postsurgical stability in the group with skeletal plus dental maxillomandibular fixation was greater than that found in the group with rigid internal fixation.

The purpose of this investigation was to determine the reliability of using the interincisal dimension as a measure of mandibular range of motion. Thirty patients who underwent mandibular advancement and 15 patients who underwent mandibular setback were included in this study. Preoperatively, a lateral cephalogram in centric relation and a second cephalogram with the mandible at maximum voluntary gape were obtained. Immediately following surgery, another centric relation cephalogram was obtained. A composite tracing of the two preoperative tracings was made to show how the mandible changed in position from the closed-mouth to the open-mouth radiographs. The proximal segment (ramus) of the postoperative cephalogram was then superimposed on the open-mouth mandibular ramus, and the distal segment of the postoperative mandible was drawn. This composite produced a tracing of what the postoperative maximal gape cephalogram would be if the same amount of condylar rotation and translation as in the preoperative tracing had occurred. The preoperative interincisal dimension was recorded on the composite tracings (factoring in any overbite or openbite) as was the would-be postoperative interincisal dimension. These measures were compared using the paired t test and Pearson's correlations to determine if there were any significant differences between them. The results showed that the interincisal dimension is a fairly reliable measure of mandibular mobility even when the length of the mandible is altered with surgery.

The purpose of this multicenter study was to review the results of treatment and identify complications in edentulous patients who were treated with the transmandibular implant. A total of 190 patients were treated in four university departments. These patients presented for treatment with mandibular bone heights that ranged from 4 to 18 mm (mean, 10 mm). After postoperative periods that ranged from 3 months to 5 years, 182 of the 190 implants (95.8%) were stable and functional. Three implants were removed due to perioperative fractures in mandibles with 4 to 6 mm of bone height. Five were removed due to infection which occurred within the first 3 months after surgery. Reversible complications that developed in 22.2% of the patients were treated successfully. The 182 implants in function demonstrated no mobility and no infrabony pockets around any of the transmucosal posts. The results of this study demonstrate that the transmandibular implant has acceptable predictability and reliability for reconstruction of patients with severe atrophy of the mandibular alveolar process.

Particle size of allogeneic bone grafts was investigated to determine its effect on revascularization and healing. Freeze-dried chips of different sizes were placed on the monkey lateral mandibular cortex, and the subsequent healing and revascularization were studied by histologic, autoradiographic, and microangiographic techniques. It appears that allogeneic bone is a reasonable substitute for autologous bone in mandibular ridge augmentation procedures.

Thirteen consecutive patients with complaints of dysfunction and pain associated with a mandibular denture were treated with the transmandibular implant. The implant was placed from a submental approach with an atraumatic surgical technique. No load was placed on the implant for 12 weeks. Patients were evaluated for pain, paresthesia, healing of the submental wound, soft tissue response, radiographic change, and mobility of the implant for a period of 2 years. Patient satisfaction was recorded at the 1- and 2-year examinations. The results demonstrate the reliability and reparability of the transmandibular implant system.