Anterior open-bite malocclusion: stability of maxillary repositioning using rigid internal fixation

A retrospective cephalometric study was performed to investigate the stability of 37 non-growing anterior open-bite cases using mini-plate rigid fixation. The sample was divided into two groups: Group A: maxillary repositioning alone (17 cases) and Group B: bimaxillary surgery (20 cases). Tracings were performed pre-operatively (T1), immediately post-operatively (T2) and at a minimum of one year follow-up (T3) (12-90 months). In Group A, the maxilla was advanced (3.8 +/- 2.8 mm, p < 0.01) and superiorly repositioned at PNS (2.8 +/- 2.3 mm, p < 0.001). In Group B, the maxilla was advanced (3.5 +/- 3.0 mm, p < 0.01) and superiorly repositioned at PNS (3.7 +/- 1.8 mm, p < 0.001); and the mandible (11.7 +/- 3.8 mm, p < 0.001), with no significant change in the vertical plane (p > 0.05). Late relapse due to condylar remodelling or resorption was found as a cause of large horizontal relapse (8.0 < x < 14.0 mm) in three cases (15%), the amount being associated with the amount of operative advancement (r = 0.7, r-sq = 40%, p < 0.01). It was concluded that the correction of anterior open bite by posterior repositioning of the maxilla using rigid fixation is a stable procedure during the follow-up period, and that in bimaxillary cases, post-operative stability depends largely on the stability of the mandibular advancement, which in turn relates to the amounts of advancement, the pre-operative anterior open bite and the mandibular plane angle.     

Effects of single- or double-jaw surgery on vertical dimension in skeletal Class III patients

The vertical facial proportions resulting from bimaxillary surgery (maxillary advancement and mandibular setback) and mandibular setback alone were evaluated. The measurements were evaluated on the preoperative and postoperative cephalometric radiographs of 20 skeletal Class III patients. The results showed that sagittal correction of the jaws caused no change in the vertical relationship of the jaws. The only significant change was an increase in occlusal plane inclination in bimaxillary surgical patients.     

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.     

Relapse patterns of two-jaw surgical correction in patients with skeletal Class III malocclusion and different vertical facial types

The aim of this study was to evaluate postoperative relapse after the surgical correction of skeletal Class III deformities of various facial patterns as a guide to surgical planning. A retrospective cohort study of 90 consecutive patients with skeletal Class III malocclusion who underwent bimaxillary surgery was performed. The surgical outcomes and postoperative stability were compared. The primary predictor variable was vertical facial type, which was classified into three groups according to the Frankfort mandibular plane angle (FMA). The primary outcome of angular and linear measurements was obtained using serial cone beam computed tomography scans obtained at time points of preoperative, 1 week after surgery, and orthodontic debonding. No significant difference in skeletal relapse was observed in patients with the different vertical facial types. The mandible displayed a forward and upward relapse in all three groups postoperatively. The patients with a low FMA exhibited a more consistent mandibular relapse pattern than those with a normal or high FMA. These findings suggest that bimaxillary surgery is clinically stable for mandibular prognathism regardless of the vertical facial pattern. However, 1–1.5 mm of overcorrection in the mandible setback should be considered in patients with a low FMA, because of the greater facial depth and consistent forward and upward mandibular relapse pattern.     

The stability of facial osteotomies. 4. Maxillary and mandibular (with or without chin) advancement with rigid internal fixation

The short-term (6 weeks postoperative) and long-term (12 months postoperative) horizontal skeletal stability of combined maxillary and mandibular advancement was evaluated by cephalometric analysis of 15 patients.
The mean horizontal advancement of the maxilla was 5.84 mm. Six weeks later a mean horizontal relapse of 0.03 mm (0.05%) was identified. The mean horizontal relapse at long-term follow-up was 0.59 mm (10.1%).
The mean horizontal advancement of the mandible was 12.35 mm at menton and 12.65 mm at pogonion. At 6 weeks, mean horizontal relapse, respectively at the above landmarks, was 0.11 mm and 0.21 mm (1.3%). The mean horizontal relapse at long-term follow-up was 2.19 mm and 1.98 mm (16.6%) respectively for the same landmarks.
Subjectively and objectively, improvements were seen in facial aesthetics and dental occlusion. The results indicate that rigid fixation of osteotomies undertaken to correct 'horizontal facial deficiency' is a surgically predictable and relatively stable procedure when reviewed up to 12 months after surgery.     

Stability of orthodontic-maxillofacial surgical treatment of anterior open bite deformities]

A sample of 267 patients with maxillary hyperplasia, a Class I or Class II occlusion and anterior open bite, collected from three different institutions, was analysed regarding stability after Le Fort I intrusion osteotomies or bimaxillary osteotomies. Skeletal and dento-alveolar stability of the maxilla, postional changes of the mandible and of incisors were evaluated on cephalometric radiographs. The stability of maxillary arch dimensions after correction of the open bite is measured on dental casts. Patients with anterior open bite, 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 showed better maxillary and mandibular stability than intraosseous wire fixation. Considerable relapse of transverse dimensions, however, was measured after orthodontic and surgical expansion. The mean overbite at the 69 months follow-up was 1.24 mm and lacking of overlap between opposing incisors was present in 19%.     

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.     

Stability after rigid fixation of simultaneous maxillary impaction and mandibular advancement osteotomies

The purpose of this study was to investigate the short- and long-term stability of bimaxillary surgery following LeFort I (LF-1) impaction with simultaneous bilateral sagittal split ramus osteotomy (BSSO) and mandibular advancement using the technique of rigid internal fixation (RIF). In order to assess the postoperative maxillary and mandibular movement pattern in 26 patients with vertical maxillary excess and mandibular deficiency, cephalograms were taken immediately preoperatively, and 1 week, 2 months, and 1 year after surgery. With paired t-test showing no statistically significant postoperative change for the point A of the maxilla from immediate postsurgery to longest follow-up (P> 0.05), the used technique of "RIF LF-I impaction and RIF BSSO advancement" tended to render excellent postsurgical stability in the horizontal (0.1+/-0.8mm mean posterior movement) and vertical (0.1+/-0.5mm mean inferior movement) direction. There was no instance of maxillary relapse of >2mm. Regarding mandibular BSSO advancement, the point B showed a significant vertical upward movement (1.6+/-1.2mm) (P< 0.001) and a slight horizontal forward movement (0.3+/-2.0mm) (P> 0.05) at 1-year follow-up. The incidence of posterior relapse of >2mm accounted for 11.5%. The data confirm the concept that the bimaxillary approach of "LF-I impaction and BSSO advancement" using the described technique of RIF is a stable procedure in the treatment of open bite patients classified as vertical maxillary excess in combination with mandibular deficiency.     

Stability of simultaneous maxillary and mandibular osteotomy for treatment of class III malocclusion: an analysis of three-dimensional cephalograms.

PURPOSE: The current investigation was undertaken to study the three-dimensional (3-D) stability of simultaneous maxillary advancement and mandibular setback using rigid fixation. The study also aimed to analyse the factors involved in postsurgical relapse by evaluation of changes in various parameters. PATIENTS: Twenty-five cases were evaluated of simultaneous Le Fort I maxillary advancement and mandibular setback using rigid fixation. METHODS: Preoperative, immediate and 6-month postoperative skeletal and dental changes were analysed using 3-D cephalograms obtained from biplanar stereoradiography. Maxillary fixation screws were used as landmarks to evaluate postoperative stability. RESULTS: The mean maxillary advancement was 3.7 mm. Relapse in the sagittal, vertical, and transverse planes was not detectable in the maxilla (p > 0.05). However, for an average mandibular setback of 5.7 mm, mean mandibular relapse was 1.1 mm or 19.3% anteriorly (p < 0.05). Surgical or postsurgical skeletal changes in the maxilla had no detectable influence on mandibular relapse (p > 0.05). Vertical alterations of the facial skeleton achieved surgically predicted the mandibular relapse (R2 = 0.27, p < 0.05). CONCLUSION: Maxillary advancement and vertical changes of +/- 2 mm did not influence the postoperative stability of the mandible. Relapse of the mandible seems to be influenced mainly by the amount and direction of the surgical alteration of mandibular position.     

Stability of skeletal class III malocclusion after combined maxillary and mandibular procedures: rigid internal fixation versus wire osteosynthesis of the mandible.

PURPOSE: The aim of this study was to evaluate skeletal stability after double-jaw surgery for correction of skeletal Class III malocclusion to assess whether there were any differences between wire and rigid fixation of the mandible. PATIENTS AND METHODS: Thirty-seven Class III patients had Le Fort I osteotomy stabilized with plate and screws for maxillary advancement. Bilateral sagittal split osteotomy for mandibular setback was stabilized with wire osteosynthesis and maxillomandibular fixation for 6 weeks in 20 patients (group 1) and with rigid internal fixation in 17 patients (group 2). Lateral cephalograms were taken before surgery, immediately after surgery, 8 weeks after surgery, and 1 year after surgery. RESULTS: Before surgery, both groups were balanced with respect to linear and angular measurements of craniofacial morphology. One year after surgery, maxillary sagittal stability was excellent in both groups, and bilateral sagittal split osteotomy accounted for most of the total horizontal relapse observed. In group 1, significant correlations were found between maxillary advancement and relapse at the posterior maxilla and between mandibular setback and postoperative counterclockwise rotation of the ramus and mandibular relapse. In group 2, significant correlations were found between mandibular setback and intraoperative clockwise rotation of the ramus and between mandibular setback and postoperative counterclockwise rotation of the ramus and mandibular relapse. No significant differences in postoperative skeletal and dental stability between groups were observed except for maxillary posterior vertical position. CONCLUSIONS: Surgical correction of Class III malocclusion after combined maxillary and mandibular procedures appears to be a fairly stable procedure independent of the type of fixation used to stabilize the mandible.     

Stabilisation of sagittal split advancement osteotomies with miniplates: a prospective, multicentre study with two-year follow-up. Part II. Radiographic parameters

This prospective study implied a two-year follow-up on a group of patients that underwent a Bilateral Sagittal Split Osteotomy (BSSO) for advancement (n=222) of the mandible that were treated in seven institutions following the same treatment protocol. The aim of Part II of this study was to correlate the clinical findings on stability and relapse as reported in Part I (clinical parameters) of this series of articles with the cephalometric findings. The mean skeletal relapse at pogonion of the whole group after two years was 0.9 mm. The clinically stable group, however, had only 0.4 mm relapse, whereas the clinical relapse group showed a mean relapse of 3.3 mm. The findings underline a relationship between the amount of advancement and relapse. The tendency for both, horizontal and vertical movement is the same, i.e., the larger the surgery effect, the larger the relapse. The angle post plane/mandibular plane showed the highest explained variance 9%. Patients with a high mandibular plane angle may be more prone to relapse. The explained variance of all considered prognostic factors together, however, is small (13%). The findings of this study express that patients with a clinical stable occlusion after a BSSO advancement, stabilised with miniplates, have a minimal to no skeletal relapse as measured on the cephalometric radiograms. The clinically non-stable group, however, appeared to have considerable skeletal relapse.     

Stability of skeletal Class III malocclusion after combined maxillary and mandibular procedures

The aim of this study was to evaluate the skeletal stability and time course of postoperative changes after surgical correction of skeletal Class III malocclusion. Combined maxillary and mandibular procedures were performed in 40 consecutive patients. Bilateral sagittal split osteotomy stabilized with wire osteosynthesis for mandibular setback and low-level Le Fort I osteotomy stabilized with plates and screws for maxillary advancement were performed. Maxillomandibular fixation (MMF) was in place for 6 weeks. Lateral cephalograms were taken before surgery, immediately postoperatively, 8 weeks after surgery, and 1 year postoperatively. Patients were divided into 2 groups according to vertical maxillary movement at surgery: a maxilla-up group with upward movement of the posterior nasal spine of 2 mm or more (group 1, n = 22), and a minimal vertical change group with less than 2 mm of vertical repositioning (group 2, n = 18). The results indicate that surgical correction of Class III malocclusion with combined maxillary and mandibular osteotomies appears to be fairly stable. One year postsurgery, maxillary stability was excellent, with a mean horizontal relapse at point A that represented 10.7% of maxillary advancement in group 1 and 13.4% in group 2. In the vertical plane, maxillary stability was also excellent, with a mean of 0.18 mm of superior repositioning at point A for group 1 and 1.19 mm for group 2. The mandible relapsed a mean of 2.97 mm horizontally at pogonion in group 1 (62% of mandibular setback) and 3.41 mm (49.7% of setback) in group 2. Bilateral sagittal split osteotomy with wire osteosynthesis and MMF was not as stable as maxillary advancement and accounted for most of the total horizontal relapse (almost 85%) observed. A trend to relapse was observed for maxillary advancement greater than 6 mm, while the single variable accounting for mandibular relapse in group 1 was the amount of surgical setback. Clockwise rotation of the ascending ramus at surgery was not correlated with mandibular relapse in relation to the type of fixation performed and therefore does not seem to be responsible for relapse.     

Semirigid fixation of the mandible in bimaxillary orthognathic surgery: stability after 18 months.

The stability of osteosynthesis with the use of semirigid mandibular fixation was evaluated in 15 patients who underwent bimaxillary procedures for correction of Class III malocclusion. All patients received rigid fixation (4 miniplates and screws) in the maxilla. Cephalometric evaluation was performed before the operation, immediately after the operation, and at least 18 months after the operation. At the 18-month follow-up, a mean mandibular relapse of 2.2 mm, associated with an additional advancement of the maxilla of 0.27 mm, was observed. The dental relationship was substantially correct. Stability of mandibular fragments in this sample of patients depended on the stability of the maxilla. In addition, neither clinical damage to the temporomandibular joint nor lesions to the neurovascular bundle were detected.     

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.     

Long-term stability of anterior open bite closure corrected by surgical-orthodontic treatment

In adults, superior repositioning of posterior maxilla with or without mandibular surgery has become the treatment method of choice to close anterior open bite. Study aim was to examine the long-term stability of anterior open bite closure by superior repositioning of maxilla or by combining maxillary impaction with mandibular surgery. The sample comprised 24 patients who underwent anterior open bite closure by superior repositioning of maxilla (maxillary group, n = 12, mean age 29.3 years) or by maxillary impaction and mandibular osteotomy (bimaxillary group, n = 12, mean age 30.8 years). Lateral cephalograms were studied prior to surgery (T1), the first post-operative day (T2) and in the long term (T3, maxillary group mean 3.5 years; bimaxillary group mean 2.0 years). Paired and two-sample t-tests were used to assess differences within and between the groups. The vertical incisal bite relations were -2.6 and -2.2 mm at T1; 1.23 and 0.98 mm at T2; and 1.85 and 0.73 mm at T3 in the maxillary and bimaxillary groups. At T3, all subjects had positive overbite in the maxillary group, but open bite recurred in three subjects with bimaxillary surgery. For both groups, the maxilla relapsed vertically. Significant changes in sagittal and vertical positions of the mandible occurred in both groups. In the bimaxillary group, the changes were larger and statistically significant. In general, the maxilla seems to relapse moderately vertically and the mandible both vertically and sagittally, particularly when both jaws were operated on. Overbite seems to be more stable when only the maxilla has been operated on.     

A comparison of the stability of single-piece and segmental Le Fort I maxillary advancements

This study retrospectively evaluated the stability of Le Fort I maxillary advancements and compared segmental and one-piece maxillary osteotomy procedures. A cephalometric analysis was performed on 26 cases of maxillary advancement. The sample comprised 11 cases of one-piece and 15 cases of segmental maxillary procedures. The tracings were superimposed and digitized by computer software, and the skeletal changes were analyzed before surgery, immediately after surgery, and at a minimum of 1 year of follow-up. Different values were compared by the paired and nonpaired t tests and were correlated by the Pearson correlation test. The significant value was set at a 95% confidence interval. The maxilla was advanced by a mean of 5.0 +/- 1.6 mm (P < 0.001), and the anterior maxilla was repositioned inferiorly by a mean of 1.5 +/- 3.3 mm (P < 0.05). The maxilla relapsed posteriorly by a mean of 0.6 +/- 1.2 mm (P < 0.05) and superiorly at the anterior maxilla by a mean of 0.8 +/- 1.1 mm (P < 0.001). Overjet and overbite did not significantly change (P > 0.05). It was concluded that maxillary advancement using rigid fixation and interpositional bone grafting in both groups was a stable procedure, particularly in the horizontal plane. In the one-piece group, there was a significantly higher relapse in the vertical plane than in the segmental group (P < 0.05), however. Minor skeletal relapse was compensated for by postoperative tooth movement, and segmental procedures are recommended when required to enhance occlusal results.     

Geometric morphometric assessment of treatment effects of maxillary protraction combined with chin cup appliance on the maxillofacial complex

The aim of this study was to investigate the treatment effects on the maxillofacial complex by maxillary protraction combined with chin cup therapy among growing children. An effective geometric morphometric assessment of cephalometric radiographs, using Procrustes analysis and thin-plate spline analysis, was applied to evaluate shape change in the craniofacial and midfacial configurations of a treated sample of 20 children with skeletal Class III malocclusion. This was compared with matched untreated skeletal Class III controls. Marked treatment induced change involved the maxilla and the mandible. Major deformation consisted of forward advancement of the maxillary complex with negligible rotation of the palatal plane and a forward direction of growth of the mandibular condyle associated with a restriction in sagittal advancement of the chin. Considerable dentoalveolar components contributed to the correction of anterior crossbite. Further detailed study of skeletofacial remodelling in response to maxillary protraction in other skeletal components, including the cranial base and the mandibular complex that contribute to Class III skeletal discrepancies, is warranted.     

常见正颌手术后咬合关系的维护和调整

目的 探讨临床常见的正颌手术后,如何很好的维护和调整上下牙列的咬合关系,为临床提供有益的参考.方法 选择骨性Ⅰ类双颌前突行根尖下截骨后徙术、Ⅱ类下颌后缩行下颌升支矢状劈开前徙术、Ⅲ类骨性反骀行下颌升支骨切开后退及合并上颌前徙术各6例患者,共18例患者.正颌手术后依据分类分别行3种不同的牵引模式进行咬合调整.结果 18例...     

Relationship between transverse dental anomalies and skeletal asymmetry.

The recognition and elimination of dental compensation is essential in presurgical orthodontic treatment to achieve successful stabilization of the occlusion after surgery. However, the relationship between a transverse dental anomaly and skeletal asymmetry is not fully understood. To evaluate this relationship, frontal cephalometric and 3-dimensional dental model analyses were carried out on 44 adult Japanese Class III patients (mean age 21 years 11 months) who required surgical orthodontic treatment. The patients were divided into 2 groups: a facial asymmetry group in which the mandibular transverse deviation exceeded +/- 1 SD from the norm, and a control group in which the mandibular transverse deviation was within +/- 1 SD of the norm. Statistical comparison with a control group showed characteristic dental anomalies in the facial asymmetry group, including asymmetry of the curve of Spee, molar inclination, dental arch form, lateral overjet, and slanting of the occlusal plane. Stepwise linear regression analysis showed that transverse and vertical skeletal asymmetry variables including the mandible and the maxilla were effective parameters for characteristic dental anomaly variables, and a significant high correlation between dental anomalies and skeletal asymmetry was found.     

Skeletal relapse after mandibular advancement and setback in single-jaw surgery

PURPOSE: The aim of this study was to identify contributing factors to skeletal relapse by analyzing cephalometric changes after bilateral sagittal split ramus osteotomy. PATIENTS AND METHODS: This study included 60 consecutive patients who underwent either mandibular advancement (30 patients) or setback surgery (30 patients). There were 36 women and 24 men (mean age, 23 years). The radiographs of these patients taken immediately before operation, at 1 week, and 14 months postoperatively were studied. To analyze the influence of hyper- and hypodivergent facial patterns on the surgical outcome, the patients were divided into 3 groups according to the mandibulo-nasal plane angle. The position of the maxilla was also taken into account. RESULTS: Measured at B-point, skeletal relapse was 1.3 mm (30%) after mean advancement of 4.4 mm and 0.8 mm (12%) after setback of 6.0 mm. The magnitude of the surgical movement correlated with skeletal relapse. However, the correlation was not linear. Advancement of greater than 7 mm is associated with an increased tendency to relapse (r=0.52), but setback of more than 12 mm with a decreased tendency (r=-0.95). The retrognathic patients with a high mandibulo-nasal plane angle (hyperdivergence) had 30% higher relapse rate. Patients with hypodivergent facial patterns had less relapse in both advancement and setback surgery. CONCLUSION: Skeletal relapse was affected by magnitude of surgical movement and different facial patterns according to the mandibulo-nasal plane angle; however, influences of both factors were different between mandibular advancement and setback.