Stability of the Le Fort I osteotomy with anterior internal fixation alone: a case series.

PURPOSE: The purpose of this case series was to evaluate the late postsurgical stability of the Le Fort I osteotomy with anterior internal fixation alone and no posterior zygomaticomaxillary buttress internal fixation. PATIENTS AND METHODS: Sixty patients with maxillary vertical hyperplasia and mandibular retrognathia underwent a 1-piece Le Fort I osteotomy of the maxilla with superior repositioning and advancement or setback. A bilateral sagittal split ramus osteotomy for mandibular advancement was also performed in 22 patients. Stabilization of each maxillary osteotomy was achieved using transosseous stainless steel wires and/or 3-hole titanium miniplates in the piriform aperture region bilaterally, with no zygomaticomaxillary buttress internal fixation. (Twelve of the 60 identified patients were available for a late postoperative radiographic evaluation.) Lateral cephalometric radiographs were taken preoperatively (T1), early postoperatively (T2), and late postoperatively (T3) to analyze skeletal movement. RESULTS: These 12 patients (5 male, 7 female) had a mean age of 24.5 years at surgery. Mean time from surgery to T2 was 41.2 days; mean time from surgery to T3 was 14.8 months. One patient received anterior wire osteosynthesis fixation, while 11 patients received both anterior titanium miniplate internal skeletal fixation and anterior wire osteosynthesis fixation. Six patients underwent Le Fort I osteotomy with genioplasty, 1 patient underwent Le Fort I osteotomy with bilateral sagittal split ramus osteotomy, and 5 patients underwent Le Fort I osteotomy with bilateral sagittal split ramus osteotomy and genioplasty. These 12 patients all underwent maxillary superior repositioning with either advancement (11 patients) or setback (1 patient). Statistically significant surgical (T2-T1) changes were found in all variables measured. In late postsurgical measurements (T3-T2), all landmarks in the horizontal and vertical plane showed statistically significant skeletal stability. CONCLUSION: This case series suggests that anterior internal fixation alone in cases of 1-piece Le Fort I maxillary superior repositioning with advancement has good late postoperative skeletal stability.     

正畸-正颌手术联合矫治骨性开(牙合)的长期稳定性研究

目的 研究正畸-正颌手术联合矫治骨性开15年后的骨性以及牙性变化.方法 本研究样本为10例成年骨性开患者,所有患者均采用正畸-正颌手术联合矫治.上颌采用了Le Fort I型截骨术,下颌采用了双侧升支矢状劈开截骨术(BSSO).选择患者在正畸治疗前(T1)、治疗后(T2)以及正颌手术后平均15年(T3)的头颅侧位片进行...     

Soft tissue changes associated with advancement genioplasty performed concomitantly with superior repositioning of the maxilla

A retrospective study of the osseous and soft tissue changes of the chins of ten patients treated for vertical maxillary excess by Le Fort I osteotomy and advancement genioplasty was undertaken. The patients were characterized by excessive lower anterior facial height, obtuse or normal nasolabial angles, prominent maxillary incisors, lip incompetence, everted lower lips, anterior open bites, lack of chin prominence, and excessive chin height. A change in the proportion of osseous to soft tissue of 1.0 to 0.87 was obtained by advancement genioplasty and concomitant superior repositioning of the maxilla by Le Fort I osteotomy.     

Postoperative skeletal stability and accuracy of a new combined Le Fort I and horseshoe osteotomy for superior repositioning of the maxilla

Postoperative skeletal stability and accuracy were evaluated in a combination of Le Fort I and horseshoe osteotomies for superior repositioning of maxilla in bi-maxillary surgeries in 19 consecutive patients. 9 underwent Le Fort I osteotomy alone (preoperative planned superior movement <3.5 mm). 10 underwent Le Fort I and horseshoe osteotomy (combination group) (preoperative planned superior movement >3.5 mm). The maxilla was osteotomized and fixed with 4 titanium Le Fort plates followed by bilateral sagittal split ramus osteotomy of the mandible, fixed with 2 semi-rigid titanium miniplates. Maxillomandibular fixation was performed for 1 week. Lateral cephalograms were obtained preoperatively, 1 week postoperatively, 3, 6, 12 months later. The changes in point A, point of maxillary tuberosity, and upper molar mesial cusp tip were examined. Discrepancy between the planned and measured superior movement of the maxilla in the Le Fort I and combination groups was 0.30 and 0.23 mm, respectively. The maxillae in both groups were repositioned close to their planned positions during surgery. 1 year later, both groups showed skeletal stability with no significant postoperative changes. When high superior repositioning of the maxilla is indicated, horseshoe osteotomy combined with Le Fort I is reliable and useful for accuracy and postoperative stability.     

Stability and morbidity of Le Fort I osteotomy with bioresorbable fixation: a randomized controlled trial

A randomized controlled clinical trial was conducted to compare the use of bioresorbable and titanium mini-plates and screws in Le Fort I maxillary osteotomies for evaluation of clinical morbidity and stability. Forty patients requiring Le Fort I osteotomies were randomly assigned to two groups. One group underwent bioresorbable mini-plate fixation and the other titanium mini-plate fixation. Stability of the maxilla was determined by serial cephalometric analysis at 2 and 6 weeks and at 3, 6 and 12 months postoperatively. Subjective and objective assessment of clinical morbidity was made prospectively. There were no differences in complications between the two fixation materials. Maxillae with bioresorbable fixation were significantly more mobile at the second postoperative week. Bioresorbable plates were initially more easily palpable, but their palpability decreased with time. Titanium plates became significantly more palpable at the 1-year follow-up. There was no difference in neurosensory disturbance between groups. Patients with bioresorbable plate fixation showed significantly more upward displacement in anterior maxilla following impaction and posterior maxilla following downgrafting from the 2nd to 6th postoperative week. The horizontal and angular relapses in the two groups were comparable. Le Fort I osteotomy with bioresorbable fixation results in no greater morbidity than with titanium fixation up to 1 postoperative year.     

Long-term skeletal stability after surgical correction in Class III open-bite patients: a retrospective study on 40 patients treated with mono- or bimaxillary surgery

Many reports have paid attention to skeletal stability after orthognathic surgery, but only few focalize attention on patients with III class III malocclusion and open bite. In this article, long-term stability (2 yr) of the maxilla and the mandible after orthognathic surgery in 40 patients with class III malocclusion and anterior open bite is evaluated. The sample has been obtained from those 420 patients with class III malocclusion treated with Le Fort I osteotomy isolated (group A, 20 patients) or in association with bilateral sagittal split osteotomy (group B, 20 patients) from 1985 to 2003. On the basis of cephalometric analysis obtained in the immediate postoperative period and 2 years after surgery, in class III patients with anterior open bite treated with mono- or bimaxillary surgery and stabilization with rigid internal fixation, the maxilla was demonstrated to remain in the postsurgical position, whereas a moderate rate of mandibular relapse dependent on the amount of surgical alteration of the mandibular position was present.     

Open bite: stability after bimaxillary surgery--2-year treatment outcomes in 58 patients

Stability after bimaxillary surgery to correct open bite malocclusion and mandibular retrognathism was evaluated on lateral cephalograms before surgery, 8 weeks post-operatively, and after 2 years. The 58 consecutive patients were treated to a normal occlusion and good facial aesthetics. Treatment included the orthodontic alignment of teeth by maxillary and mandibular fixed appliances, Le Fort I osteotomy, and bilateral sagittal split ramus osteotomy. Twenty-six patients also had a genioplasty. Intra-osseous wires or bicortical screws were used for fixation. Twenty-three patients had maxillo-mandibular fixation (MMF) for 8 weeks or more, six for 4-7 weeks, 14 for 1-3 weeks, and 15 had no fixation. At follow-up 2 years later, the maxilla remained unchanged and the mandible had rotated on average 1.4 degrees posteriorly. Seventeen patients had an open bite. Among them, eight patients had undergone segmental osteotomies. The relapse was mainly due to incisor proclination. The most stabile overbite was found in the group with no MMF after surgery.     

Long-term dentofacial stability after bimaxillary surgery in skeletal Class III open bite patients

The purpose of this study was to evaluate long-term dentofacial stability after bimaxillary surgery in skeletal Class III open bite patients. Twenty-three Japanese adults (5 males, 18 females) were randomly selected as the experimental group from the files of Tohoku University Dental Hospital according to the following criteria: (1) skeletal Class III malocclusion with anterior open bite, (2) simultaneous Le Fort I and sagittal split ramus osteotomies, and (3) complete set of cephalograms taken at predetermined intervals until 5 years after debonding. Based on the manner of maxillary surgical repositioning, they were divided into the following 2 groups: (1) impaction group of 13 subjects (2 males, 11 females) who had maxillary superior repositioning without rotation of the palatal plane, and (2) rotation group of 10 subjects (3 males, 7 females) who had maxillary repositioning with clockwise rotation of the palatal plane. These patients were compared to a control group of 11 adults (1 male, 10 females) with skeletal Class III malocclusion without open bite who underwent bimaxillary surgery by the same techniques. Our data showed that overbite stability in the rotation group was better than that in the impaction group. This suggests that clockwise rotation of the palatal plane, which moves the anterior maxillary structures down, is an effective way to produce a reasonably stable correction of the anterior open bite. In contrast, superior repositioning of the maxilla that significantly rotates the mandible in the closing direction should be applied with caution.     

Surgical accuracy in Le Fort I maxillary osteotomies

The surgical outcome of planned movements of Le Fort I osteotomies is dependent on the surgeon's ability to achieve such movements intraoperatively. Our aim was to assess the surgical accuracy achieved for 30 consecutive patients undergoing Le Fort I osteotomies treated by one maxillofacial surgeon and his team. Method: Intraoperative control of the mobilized maxilla vertically was achieved by a combination of a nasion screw as the external reference point and bony marks above and below the osteotomy cuts intraorally. Movements horizontally and transversely were controlled with occlusal wafers. The surgical accuracy of maxillary movements vertically and horizontally (anteroposteriorly) were assessed by standard lateral cephalometric tracings of radiographs taken within two weeks prior to operation and 48 hours afterwards. Audit targets were arbitrarily set to be satisfactory when the difference between planned movements and actual movements as measured on the cephalometric tracings were 2 mm or less. Results: The mean (SD) difference from planned vertical movements of the anterior maxilla was 0.37 mm (SD 0.64) and horizontal movements 0.85 mm (SD 0.91). Ninety-seven percent (29/30) of anterior maxillary movements in the vertical dimension, 90% (27/30) of anterior maxillary movements in the horizontal dimension and 87% (26/30) of movements in both dimensions had a difference of 2 mm or less. These results were comparable with the reported 'gold standard'. Conclusion: Good surgical accuracy in positioning the mobilized maxilla in Le Fort I osteotomies can be achieved with the use of external and internal reference points.     

Importance of soft tissue for skeletal stability in maxillary advancement in patients with cleft lip and palate.

OBJECTIVE: Assessment of stability of the advanced maxilla after two-jaw surgery and Le Fort I osteotomy in patients with cleft palate based on soft tissue planning. SUBJECTS: Between 1995 and 1998, 15 patients with cleft lip and palate deformities underwent advancement of a retruded maxilla, without insertion of additional bone grafts. Eleven patients had bimaxillary osteotomies and four patients only a Le Fort I osteotomy. Relapse of the maxilla in horizontal and vertical dimensions was evaluated by cephalometric analysis after a clinical follow-up of at least 2 years. RESULTS: In the bimaxillary osteotomies, horizontal advancement was an average 4 mm at point A. After 2 years, there was an additional advancement of point A of an average of 0.7 mm. In the mandible, a relapse of 0.8 mm was seen after an average setback of 3.9 mm. In the four patients with Le Fort I osteotomy, point A was advanced by 3.8 mm and the relapse after 2 years was 0.9 mm. Vertical elongation at point A resulted in relapse in both groups. Impaction of the maxilla led to further impaction as well. CONCLUSION: Cephalometric soft tissue analysis demonstrates the need for a two-jaw surgery, not only in severe maxillary hypoplasia. Alteration of soft tissue to functional harmony and three-dimensional correction of the maxillomandibular complex are easier to perform in a two-jaw procedure. It results in a more stable horizontal skeletal position of the maxilla.     

The skeletal stability of one-piece Le Fort 1 osteotomy to advance the maxilla; Part 1. Stability resulting from non-bone grafted rigid fixation

During the past decade, we have increasingly preferred to do a one-piece Le Fort 1 osteotomy to advance the maxilla, sometimes in isolation to treat patients with maxillary retrusive skeletal Class III patients or combined with mandibular advancement to treat bimaxillary retrusive skeletal Class II. Clinical impressions of rigid fixation techniques have indicated that there is improved stability when compared with wire fixation. There are few studies in the literature that have addressed relapse following one-piece Le Fort 1 osteotomy to advance the maxilla. Such surgery involves one single spatial movement and thereby eliminates other possible surgical variables, which may impact on the degree of stability achievable postoperatively. We studied 45 patients who had undergone a uniform one-piece maxillary advancement with elimination of controllable variables, apart from 15 patients who had simultaneous mandibular advancement. Rigid fixation was adopted throughout the study. The mean surgical change documented was 7.42 mm. The mean stability calculated at 12 months revealed a relapse of 0.72 mm (10%). This was not significant (P = 0.3). We conclude that the Le Fort 1 advancement osteotomy is a stable and surgically predictable procedure that gives only slight relapse at 12 months.     

Biomechanical evaluation of Le Fort I maxillary fracture plating techniques.

PURPOSE: This study used a biomechanical model to examine fundamental questions about rigid plate fixation treatment for maxillary Le Fort I fractures. Specifically, we sought to elucidate the principal strain patterns generated in miniplates and bite force transducers secondary to all masticatory forces, as well as the amount of permanent deformations incurred due to these loading forces. MATERIALS AND METHODS: Forty polyurethane synthetic maxillary and mandibular replicas were used to simulate the mandible and maxilla. Ten replicas were controls (group A). The other 30 were divided into 3 groups (10 each), according to the fixation techniques of 3, 2, and 1 miniplates each side (groups B-D), that were osteotomized in the Le Fort I fracture line on the maxilla. Different forces of masseter medial pterygoid, temporalis, and lateral pterygoid muscles were loaded onto the replicas to simulate different functional conditions (anterior incisor, premolar, and molar clenching). Rosette strain gauges were attached at predefined points on the plates and the bite force transducer to compare the stability and bite force of the different fixation methods for maxillary Le Fort I fractures. RESULTS: Statistically significant differences were found for the deformation of the plates among fixation techniques. The order of stability for each technique was: group B greater than group C greater than group D. In regard to bite force, no difference was found between those found with group A and group B (P > .05), whereas the bite forces of groups C and D were less than those of group A (P < .05). CONCLUSIONS: The fixation of 3 miniplates on each side provides sufficient stability and restores the bite force to the level of the intact maxilla. "The ideal fixation" with 2 miniplates on each side restores 90% of the bite force, and there were more deformations of the miniplates with the "ideal fixation" compared to those found with group B. Group D fixation produced the worst effects for the treatment of maxillary Le Fort I fractures with a weak bite force and insufficient stability.     

Stability of maxillary advancement for correction of skeletal Class III malocclusion after combined maxillary and mandibular procedures: preliminary results of an active control equivalence trial for semirigid and rigid fixation of the maxilla

In this paper preliminary results are presented of a prospective study designed to examine the effect of maxillary fixation methods on postoperative stability. The purpose of this study was to evaluate the stability of Le Fort I osteotomy stabilized with semirigid fixation of the maxilla (SRMF) or rigid fixation of the maxilla (RMF). All patients had skeletal Class III malocclusion and underwent bimaxillary surgery (Le Fort I maxillary advancement with or without superior repositioning and bilateral sagittal split osteotomies of the mandible). Standardized cephalometric analysis was performed on serial radiographs of 42 patients immediately before surgery, 1 week after surgery, after release of fixation, and 1 year postoperatively. The patients were randomized into 2 treatment groups: 23 patients received RMF (group A), and 19 patients received SRMF (group B). Within the groups, patients showed good stability with regard to their baseline characteristics. To show the therapeutic equivalence of the 2 treatments, analysis of the recorded data followed the approach for an equivalence trial. The mean surgical advancement was 5.34 +/- 1.50 mm for group A and 4.51 +/- 1.37 mm for group B. The mean amount of postsurgical relapse was 0.98 +/- 1.27 mm for group A and 0.30 +/- 1.04 mm for group B. Group A patients experienced 93% of their relapse (0.92 mm) during fixation, while group B patients experienced 96% of their relapse (0.29 mm) after release of fixation. RMF provided better stability than SRMF for all maxillary landmarks in the vertical plane. All considered points both in horizontal and vertical plane exhibited full equivalence for 95% confidence intervals, which seems to indicate equivalent stability between the surgical procedures.     

人物介绍俞光岩教授

人物介绍俞光岩教授俞光岩，男，１９５２年３月出生。浙江渚暨人。１９７９年８月毕业于浙江医科大学口腔系，１９８２年及１９８７年先后获北京医科大学口腔颌面外科医学硕士及医学博士学位。１９９０年以高级访问学者身份赴德国汉堡大学病理研究所访问进修一年。１９９...     

Superior repositioning of the maxilla: stability and soft tissue osseous relations.

The skeletal stability and soft-tissue changes associated with superior repositioning of the maxilla by Le Fort I osteotomy or simultaneous anterior and posterior maxillary osteotomies was studied in thirty patients by means of a computerized craniofacial model. Excellent skeletal stability was demonstrated 14 months postoperatively. Postsurgically, the reduction in lower face height and amount of maxillary incisor exposure resulted in improved facial balance. The use of a computerized osseous and soft-tissue craniofacial model has added a new dimension to evaluation of surgical changes associated with correction of dentofacial and craniofacial deformities.     

Skeletal and dento-alveolar stability after surgical-orthodontic treatment of anterior open bite: a retrospective study.

The aim of this investigation was to assess skeletal and dento-alveolar stability after surgical-orthodontic correction of skeletal anterior open bite treated by maxillary intrusion (group A) versus extrusion (group B). The cephalometric records of 49 adult anterior open bite patients (group A: n = 38, group B: n = 11), treated by the same maxillofacial surgeon, were examined at different timepoints, i.e. at the start of the orthodontic treatment (T1), before surgery (T2), immediately after surgery (T3), early post-operatively (+/- 20 weeks, T4) and one year post-operatively (T5). A bimaxillary operation was performed in 31 of the patients in group A and in six in group B. Rigid internal fixation was standard. If maxillary expansion was necessary, surgically assisted rapid palatal expansion (SRPE) was performed at least 9 months before the Le Fort I osteotomy. Forty-five patients received combined surgical and orthodontic treatment. The surgical open bite reduction (A, mean 3.9 mm; B, mean 7.7 mm) and the increase of overbite (A, mean 2.4 mm; B, mean 2.7 mm), remained stable one year post-operatively. SNA (T2-T3), showed a high tendency for relapse. The clockwise rotation of the palatal plane (1.7 degrees; T2-T3), relapsed completely within the first post-operative year. Anterior facial height reduction (A, mean -5.5 mm; B, mean -0.8 mm) occurred at the time of surgery. It can be concluded that open bite patients, treated by posterior Le Fort I impaction as well as with anterior extrusion, with or without an additional bilateral sagittal split osteotomy (BSSO), one year post-surgery, exhibit relatively good clinical dental and skeletal stability.     

Stability after surgical-orthodontic corrective of skeletal Class III malocclusion. 3. Combined maxillary and mandibular procedures

Stability after combined Le Fort I and bilateral sagittal split osteotomies was reviewed in 51 patients with skeletal Class III malocclusion. Because vertical changes in the position of the maxilla affect both the vertical and anteroposterior positions of the mandible, the sample was subdivided by the direction of vertical movement of the maxilla at surgery. Excellent postsurgical stability was observed in the long-face Class III patients in whom upward and forward movement of the maxilla was combined with ramus osteotomy to prevent excessive forward rotation of the mandible. When the maxilla was moved forward and the mandible set back with minimal vertical change, moderate relapse tendencies were observed in both jaws, but most of the correction was maintained at 1 year. When the maxilla was moved down and forward while the mandible was set back, moderate vertical relapse of the maxilla and anteroposterior relapse of the mandible followed. Stability of the downward movement of the maxilla was, on average, better than that resulting from maxillary surgery alone.     

Stability after maxillary segmentation for correction of anterior open bite: A cohort study of 33 cases

The aim of this cohort study was to evaluate the stability after multi-segmentation of the maxilla for correction of anterior open bite deformities. A total of 33 patients who underwent segmented maxillary osteotomy between 1994 and 2006 were included in the study. Rigid fixation with plates and postsurgical intermaxillary fixation for 6 weeks was applied to each patient. All patients were then followed in a standardized examination procedure at months 6, 12, 18 and up to 30 months postoperatively. Vertical and horizontal relation of the incisors was measured both clinically and on cast models. The main finding was that statistically significant relapse was found vertically, whereas the horizontal relationship to the mandible was unchanged. The vertical relapses were predominantly seen in patients with severe open bite evident preoperatively.     

RIF技术在陈旧性面中份骨折所致牙颌面畸形的外科修复与功能重建中的应用

目的：探求复杂的陈旧性面中份骨折后其牙、颌、面畸形修复与功能重建的有效治疗方法。方法：对2000年-2003年间收治的23例复杂的陈旧性面中份骨折病例，术前进行影像学分析和模型外科设计，并取得上颌骨分块截骨术后的定位舍板，以预测和指导手术。手术采用口内切口，通过Le FortⅠ型或Le FortⅡ型截骨术，将上颌骨截断降下，按模型材料设计要求将上颌骨分块，并将分块后的上颌骨块固定于合板上。行上、下颌颌间栓结，待确定恢复正常咬合关系后，用微型夹板行上颌骨坚固内固定(rigid internal fixation，RIF)，或是辅以头皮冠状切口，将错位愈合的颧骨、颧弓复住，固定。结果：本组病例一周后伤口均Ⅰ期愈合拆线，2-3周拆除颌间牵引固定，骨块固定，咬合关系正常，颜面外形恢复满意。结论：正颌外科术式或辅以其他术式以及RIF技术的应用是治疗复杂的陈旧性面中份骨折的有效方法。     

Dynamic analysis of maxillary perfusion during Le Fort I osteotomy using indocyanine green

The aim of this study was to evaluate the dynamic perfusion of the maxilla during various stages of a Le Fort I osteotomy using indocyanine green (ICG) dye angiography. This was a retrospective evaluation of patients who underwent a Le Fort I osteotomy. ICG was used to assess perfusion at specific time points during the procedure. Twenty-four patients underwent a Le Fort I osteotomy with dynamic perfusion ICG angiography. Statistically significant differences in perfusion were noted at all three locations assessed between preoperative (T0), post down-fracture (T1), and postoperative (T2) time points. When controlling for mean arterial pressure, statistically significant differences were noted at all three locations assessed between T0 and T1, and between T0 and T2. There were no statistically significant differences in patient age, heart rate, preservation or sacrifice of the descending palatine arteries, or conventional vs. segmental Le Fort I osteotomies across T0, T1, and T2. In conclusion, there was a statistically significant decrease in perfusion, as assessed by intraoperative dynamic angiography, to the anterior maxilla following maxillary down-fracture. Patient age, conventional vs. segmental Le Fort I osteotomy, changes in mean arterial pressure and/or heart rate, and preservation of the descending palatine vessels had no statistically significant effect on perfusion.