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Forty-one patients who underwent bilateral sagittal ramus osteotomy for large mandibular advancements were evaluated by retrospective cephalometric analysis for rotational and linear stability of the proximal and distal segments of the mandible. The patients were grouped by the number of screws used in fixation (three versus four 2-mm bicortical screws) and matched for the amount of advancement measured from changes in mandibular body length. The group with four fixation screws did receive significantly larger advancements relative to the cranial base than did the group with three screws. However, the pattern of postoperative change was similar for the two groups. There was no higher rate of relapse seen in those patients with high mandibular plane angles, genioplasties, mandibular constriction with a symphyseal osteotomy, or open bites preoperatively, nor did the number of screws used in fixation affect changes seen in those patients. Factors associated with both relapse and continued postoperative movement in the direction of advancement independent of the screw fixation group were identified.

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The purposes of this study are to determine the stability of surgical mandibular constriction with a midline osteotomy and to evaluate the periodontal and temporomandibular joint responses. A symphyseal osteotomy to facilitate mandibular construction was performed in 15 patients to correct transverse discrepancies. At the same time a surgical anterior or posterior repositioning of the mandible was done by using a bilateral sagittal osteotomy of the vertical ramus. Tomograms in the coronal plane including the mandibular second molars were taken preoperatively (T1), immediately postoperatively (T2) and 8 weeks postoperatively (T3). Linear measurements between the cortical borders of the mandible were assessed from the tomograms at each time period. Median surgical and postoperative changes in mandibular width were determined. When evaluating the entire group no statistically significant change in the surgical constriction was found postoperatively (T2 and T3), although there was some individual variability. An examination of the periodontal response at the osteotomy site revealed no statistically significant change between the initial and the 5-month postoperative examinations. No changes in joint noise were detected postoperatively, and all mandibular joint movements returned to preoperative values except for excursive movements. Mandibular constriction with a midline osteotomy on conjunction with a bilateral sagittal osteotomy was found to be a stable modality for correcting transverse disharmonies.

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A surgical approach to treatment was required for this 35-year-old patient to correct a malocclusion characterized by a bilateral buccal crossbite. Surgical procedures included a LeFort 1 osteotomy to reduce maxillary width and correct the vertical asymmetry. The mandible was lengthened with a bilateral sagittal split osteotomy. Treatment options for the nongrowing patient are limited in the correction of severe skeletal disharmonies.

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Forty-three patients who underwent surgical lengthening of the mandible using an inverted L osteotomy, bone grafting, and rigid internal fixation between the mandibular segments were evaluated by retrospective cephalometric analysis for longitudinal skeletal and dental changes. Postoperative response (means = 1 year 9 months) was found to demonstrate a high level of stability with some individual variability. No propensity for relapse was observed in any postoperative time interval. Condylar repositioning postoperatively appeared to be an important factor in those patients who exhibited any relapse tendency. Overall postoperative stability of this surgical/fixation technique appears to be significantly improved compared with previously documented techniques.

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Eighty patients, who had previously been evaluated by an oral surgeon and an orthodontist as requiring orthognathic surgery, completed questionnaires rating their perceptions of their own profiles. Half of the patients had decided to undergo surgical correction of their jaw deformities, while the other half had decided against surgical treatment. In addition, booklets containing pretreatment photographs of all 80 patients were mailed to 37 oral surgeons, 46 orthodontists, and 43 lay persons. These three groups of evaluators rated the patients' profiles, using the same rating scales that the patients had used. Cephalometrically, the two patient groups were statistically the same in all skeletal and soft-tissue measures except for ANB (mean difference = 1.8 degrees) and soft-tissue AN-pogonion (mean difference = 2.4 degrees). Differences in these dimensions were considered in subsequent data analyses. Results of this study support the following conclusions: In spite of the fact that surgical treatment may be recommended by dental specialists and indicated by cephalometric measurements, self-perceptions of profile are more important in the patient's decision to elect surgical correction; the perception by others that the profiles of patients deciding against surgery are closer to ideal may have some influence on their decision against surgical correction of their jaw deformities; oral surgeons and orthodontists evaluate facial profiles similarly, but surgeons are more likely to recommend surgical correction; lay persons are more likely to rate an individual's profile as being normal than are dental specialists in orthodontics and oral surgery; in contrast, individuals perceive their own profiles differently than orthodontists, oral surgeons, and lay persons, particularly with respect to the mandibular and dentoalveolar dimensions.

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Long-term response of the anterior open-bite malocclusion was evaluated in forty-one white subjects who had undergone orthodontic treatment and were out of retention a minimum of 9 years 6 months. The purpose of the study was threefold: (1) to make cephalometric comparisons between a sample of open-bite patients and a sample with normal cephalometric standards, (2) to evaluate treatment and posttreatment changes that occurred in treated open-bite patients, and (3) to search for predictors and associations of value. Changes occurring across time in the open-bite patients were analyzed by computer means using pretreatment, posttreatment, and long-term cephalometric radiographs and dental casts. An analysis of subgroups was reviewed to compare dentoalveolar and skeletal relationships of both stable and relapse groups. More than 35% of the treated open-bite patients demonstrated a postretention open bite of 3 mm or more, with the relapse subgroup demonstrating across-time, less mandibular anterior dental height, less upper anterior facial height, greater lower anterior facial height, and less posterior facial height. Neither the magnitude of pretreatment open bite, mandibular plane angle, nor any other single parameter of dentofacial form proved to be a reliable predictor of posttreatment stability.

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Assessment at least 10 years postretention of sixty-five cases previously treated in the permanent-dentition stage with first-premolar extractions, traditional edgewise mechanics, and retention revealed considerable variation among patients. The long-term response to mandibular anterior alignment was unpredictable; no variables, such as degree of initial crowding, age, sex, Angle classification, etc., were useful in establishing a prognosis. Typically, arch width and length decreased after retention, regardless of treatment expansion or constriction. Two thirds of the patients had unsatisfactory lower anterior alignment after retention. Cases that were minimally crowded before treatment usually became more crowded, while initially severe crowding cases usually moderated.

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