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The aim of this study was to assess post-operative stability of bilateral sagittal split set-back osteotomies using two miniplates and clinical parameters including nerve function, TMJ function, occlusal relapse and patient satisfaction. The stability was measured on cephalometric radiographs and possible condylar alterations on orthopantomograms. This prospective study implied a 2-year follow-up on a group of 24 patients. The same protocol was used at six participating institutions at which the patients were treated. A stable occlusion without appreciable relapse was seen in 91% after 2-year follow-up. Only two patients in this study had mild occlusal relapse. The mean skeletal horizontal relapse at pogonion of the whole group, after 2 years was 1.1mm and appeared to be directed backwards. At occlusal level, however, the mean relapse was 1.2mm forwards. The function of the inferior alveolar nerve 2 years post-operatively was reported to be normal in approximately 70% of the patients, yet 80% had no complaints about nerve dysaesthesia. In approximately 21% of the patients, signs and symptoms of TMJ dysfunction had disappeared. Another group (10%), however, without pre-operative signs and symptoms of TMJ dysfunction developed these signs or symptoms post-operatively. No condylar remodelling or resorption was seen in this group of patients. The sagittal split set-back osteotomy fixed with miniplates appeared to be a relatively save and reliable procedure giving rise to adequate results and a high degree of patients satisfaction.

The principal aim of this study was to assess the postoperative stability of bilateral sagittal split osteotomies (BSSO) using two miniplates. Part I reports on the clinical results including treatment characteristics, nerve functions, TMJ function, occlusional relapse and patient satisfaction. This prospective study evaluated a group of 222 patients who underwent a BSSO for mandibular advancement. The same treatment protocol was used at seven participating institutions at which the patients were treated. A stable occlusion without appreciable relapse was seen in 84% after 2 years of follow-up. A considerable minority (16%) had occlusal relapse. There were no clinical parameters that pointed towards a high risk for relapse except age. The mean operation age of the relapse group was 20.7 years (SD 6.7) and in the stable group 26.1 years (SD 8.2). The function of the inferior alveolar nerve 2 years postoperatively was reported to be normal in approximately 88% of the patients, while 94% had no complaints about nerve dysaesthesia. In approximately 56% of the patients with pre-existing TMJ-dysfunction these signs and symptoms had disappeared. Another group of patients, however, without TMJ-dysfunction preoperatively (22%) developed signs or symptoms of TMJ-dysfunction postoperatively. The sagittal split osteotomy fixed with miniplates appeared to be a relatively safe and reliable procedure giving rise to a high degree of patient satisfaction, despite the fact that some occlusal relapse was seen.

The results are reported on six patients who underwent a modified quadrangular osteotomy to avoid dysaesthesia of the infraorbital nerve. The suggested modification served its purpose well, while the functional and aesthetic results were excellent.

The aim of this retrospective study was to evaluate the long-term treatment results of 26 patients who developed progressive condylar resorption (PCR) following a bilateral sagittal split advancement osteotomy (n= 19) or a bimaxillary osteotomy (n=7). PCR was diagnosed clinically and from a comparison of pre- and postoperative cephalometric and orthopantomographic radiographs. The preoperative condylar configuration and resorption pattern were assessed distinguishing between 'deep bite' and 'open bite'. Patients with 'deep bites' tended to have more resorption on the superior site of the condyle, while 'anterior open bites' often had resorption on the superior and anterior sites of the condyle. The patients were divided into 2 groups, one receiving non-surgical treatment that included splints, orthodontics with or without extractions and restorative dentistry. The second group underwent repeated surgery to treat skeletal relapse. Thirteen patients who underwent non-surgical treatment after orthognathic surgery had satisfactory results from orthodontic dental compensation, although only 3/13 had Class I occlusion. Another 13 patients had unacceptable occlusal and/or esthetic results and, therefore, underwent a second surgery. Following surgery, 7 patients had satisfactory occlusal and esthetic results and were skeletally stable. Four patients had 40-80% relapse, but with a stable occlusion. Two patients had 120% and 100% relapse, respectively, and needed a third surgical intervention. The first patient had a stable occlusal and esthetic result with approximately 30% relapse at pogonion, but the second patient still had an unstable malocclusion with again 100% relapse. It appeared that, without surgical intervention after PCR, further resorption ceased after approximately two years. Second surgery appeared to produce variable results, but, in this series, the majority had significant improvement.

A sample of 267 patients with maxillary hyperplasia, a Class I or Class II/I occlusion and anterior vertical open bites, collected from three different institutions, was analysed regarding stability after surgical corrections. Skeletal and dento-alveolar stability of the maxilla, and positional changes of the mandible and of the incisors were evaluated. All patients underwent Le Fort I intrusion osteotomies and in 92 patients segmentation of the maxillae was performed. An additional bilateral sagittal split advancement osteotomy was performed in 123 patients. Intraosseous wire fixation was used in 153 patients and rigid internal fixation in 114 patients. Cephalometric radiographs were collected before orthodontic treatment, before surgery, immediately after surgery, one year postoperatively and at the latest follow up. The mean follow up was 69 months (range 20-210 months). It can be concluded that patients with anterior open bites, treated with a Le Fort I osteotomy in one-piece or in multi-segments, with or without bilateral sagittal split osteotomy, exhibited good skeletal stability of the maxilla. Rigid internal fixation produced the best maxillary and mandibular stability. The mean overbite at the longest follow up was 1.24 mm and a lack of overlap between opposing incisors was present in 19%. The overbite did not differ significantly between the different treatment procedures, probably due to compensatory movements of the mandibular and maxillary incisors.

The data of 2049 patients, who underwent maxillofacial orthopaedic surgery, were retrospectively analysed for major intra- and immediate postoperative complications. Immediate life-threatening complications were very rare. They can in most cases be avoided by good anaesthetic and surgical techniques and adequate postoperative care. The most frequently encountered problem in maxillary surgery is excessive blood loss, whilst a compromised airway due to swelling is the most frequent complication in mandibular surgery. Good co-operation between anaesthetist and surgeon is essential to prevent major intraoperative and immediate postoperative problems.

Eleven patients (9 UCLP, 2 BCLP) were treated with segmental osteotomies with or without osteotomies at the Le Fort I level and simultaneous bone grafting of the alveolo-palatal clefts at adult age. These patients were clinically and radiographically evaluated after a mean follow-up period of 59 months (range 39-110 months). One patient showed complete dentoalveolar relapse, whereas the skeletal stability after miniplate fixation proved to be adequate in all cases. Only one patient presented with a persisting oro-nasal fistula. In six cases, the alar base asymmetry had improved to such an extent that further nasal corrections were not necessary. The procedure described is a reliable technique to graft the alveolo-palatal cleft and reposition the dentoalveolar segments simultaneously in those adult cleft palate patients who had no previous alveolar bone grafting.

Skeletal stability, temporomandibular joint (TMJ)-function, and inferior alveolar nerve function were evaluated in 103 patients with mandibular hypoplasia who were treated with bilateral sagittal split osteotomies to advance the mandible. Stable internal fixation was obtained with miniplates and four monocortical screws. The follow-up period was at least 24 months (average: 32 months; maximum: 60 months). The average B-point advancement was 5.85 mm. Ninety-three patients of 103 (90.3%) had no appreciable relapse at B-point. Eight (7.7%) patients had relapse because of condylar resorption. Maximum mouth opening decreased an average of 1 mm. Sixty-eight percent of the patients with preoperative TMJ-dysfunction symptoms reported improvement or resolution of their symptoms. Sixteen percent experienced worsening of their TMJ symptoms. Permanent neurosensory deficits were identified in five patients (five sides).

Nineteen patients underwent Le Fort I osteotomy and inferior maxillary repositioning. Miniplates were used to maintain the maxilla in its new position. The patients were followed from 12 to 58 months, postoperatively. Fourteen patients were considered to be stable over the long term. Five patients had a long-term relapse of more than 30%. A tendency towards greater relapse was seen in patients with more than 5 mm inferior repositioning, and in patients who had concurrent segmental osteotomies of the maxilla. In spite of the use of miniplates, there continues to be an element of unpredictability with regard to vertical relapse after inferior maxillary repositioning, and this may be related to soft-tissue influences.

A technique is described involving the combined use of mandibular ramus osteotomies and body step osteotomies. The combined use of these osteotomies enables the surgeon to solve some of the most complicated skeletal and occlusal problems. The method has proved to be safe in that no complications have occurred in the 7 patients reported.

34 patients (40 sides) received alveolo-palatal bone grafts for closure of the residual cleft, thus guiding a lateral incisor or canine into the arch. Long-term follow-up shows that in 41% of the patients uninterrupted arches were achieved with a normal relationship by orthodontic treatment only. 38% needed segmental osteotomies to eliminate the edentulous space, and in only 20% were bridges made to restore the dental arch. 9 (25%) patients still required a Le Fort I advancement osteotomy, despite optimal orthodontic treatment. The use of segmental osteotomies for eliminating edentulous spaces in cleft palate patients is discussed, and their advantage in relation to nasal base support is emphasized. It should be the aim to achieve in every cleft palate patient a complete archform without the need for bridges or removable prostheses. A rational orthodontic-surgical approach to the cleft, lip and palate patient is suggested with respect to naso-maxillary growth and development.

The non-surgical treatment of mandibular condylar fractures, may occasionally result in articular imbalance and temporomandibular joint dysfunction. This may be attributed to condylar head displacement and resorption, resulting in a shortened vertical ramus and lost posterior vertical facial height. Restoring the vertical ramus height is essential in the treatment of such dysfunction, and may be accomplished by unilateral, or bilateral ramus osteotomies. Four examples of patients treated with mandibular ramus osteotomies to restore vertical ramus height, with subsequent improvement in occlusal balance and function are presented. The use of the sagittal split mandibular osteotomy and the external vertical ramus osteotomy, stabilized with small osseous plates, and monocortical screws, is discussed.

Skeletal stability was evaluated in 20 patients with mandibular hypoplasia, treated with bilateral sagittal split osteotomies to advance the mandible. Stable internal fixation was obtained using osseous miniplates and monocortical screws. Intermaxillary fixation was released after 5.15 days (range 1 to 11 days). The average B-point advancement was 6.07 mm (range 2.25 to 17.5 mm) and the average Pogonion-point advancement was 5.39 mm (range 1.75 to 14 mm). Mandibular range of motion, TMJ dysfunction and neurosensory deficits were also evaluated. The follow-up period averaged 8.85 months (range 6 to 14 months) and final evaluations were made after completion of orthodontics. Relapse measured at B-point was 10.7% and at Pogonion was 18.7%. Maximal opening decreased an average of 0.47 mm. Symptoms in 8 patients with TMJ dysfunction resolved, while 3 others developed TMJ dysfunction following surgery. Neurosensory deficits were subjectively identified in 9 patients (10 sides) and were objectively measured in 5 patients (5 sides).

Two groups of 20 patients who were treated for mandibular hypoplasia by surgical lengthening of the mandible using the bilateral sagittal split ramus osteotomy were followed pre- and postoperatively using serial lateral cephalograms. One group of patients was treated without internal fixation and the second group, with superior border intraosseous osteosynthesis wiring. Both groups were evaluated for postoperative skeletal and occlusal changes and the results were compared. A notably greater amount of relapse was observed in the group of patients in whom no intraosseous wiring was used.

The use of segmental osteotomies to treat surgically severe malocclusion in cleft patients is discussed. The coordinated approach by orthodontist and surgeon is advocated and the advantage of such an approach is stressed. The method allows for the simultaneous correction of the skeletal deformity and closure of residual oro-nasal perforation. The relapse tendency in both antero-posterior and transverse dimensions appeared to be minimal as found in this study of 18 patients.

A study of 20 patients who underwent augmentation of an atrophic mandible by a "three-piece" osteotomy and interpositional bone graft technique is presented. The results show a reduced rate of bone resorption in the posterior regions and a reduced incidence of sensory nerve disturbances in comparison with previous visor/sandwich techniques.

The technical details of a modified procedure for separation of the pterygoid plates in low-level maxillary osteotomies is described. The cut is made through the tuberosity and ends at the posterior aspect of the hard palate, medial and anterior to the pterygomaxillary fissure. This technique provides several advantages over the more classically described posterior vertical cut through the pterygomaxillary suture. The major advantages are that it is anatomically less hazardous and allows greater mobility of the segments. It also permits a larger vascular pedicle to be maintained.

The application of the posterior segmental maxillary osteotomy to the problem of edentulous space closure was studied in 30 patients so treated. The degree of success was based on several criteria, which included stability, periodontal health, occlusion, and response to treatment. A simplified surgical technique is described and useful surgical aids are demonstrated. The existing literature is reviewed in the light of present findings.