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Background and Objectives: High-angle Class II malocclusion is considered challenging to treat to a stable result and, although studies report treatment outcome in terms of morphology, patient satisfaction has not been addressed. The objectives of the present study were to examine patients' motives for treatment and satisfaction with the results., Material and Methods: A structured questionnaire was distributed 3 years post-operatively to 93 consecutively treated patients with an initial diagnosis of mandibular-plane angle (ML/NSL) ≥34.0 degrees and ANB angle ≥4.0 degrees. Three surgical subsamples were defined: one-piece Le Fort I, bilateral sagittal split osteotomy, or a combination of the two (Bimax). Lateral cephalometric radiographs were used to assess morphological characteristics and post-treatment changes., Results: Questionnaire participation was 69.8 per cent. The most frequently reported motives for seeking treatment were to improve oral function (85.0 per cent) and dental appearance (71.7 per cent). Thirty per cent were very satisfied, 53.3 per cent were satisfied, and 16.7 per cent were dissatisfied with the overall treatment result. Dissatisfaction was associated with a persisting post-treatment anterior open bite (AOB), horizontal relapse at B point, and with sensory impairment., Conclusions and Implications: A higher rate of dissatisfaction was found than what has usually been reported for othognathic surgical patients, and this was associated with a persisting AOB. In addition, mandibular relapse and impaired sensory function were related to dissatisfaction and are associated with mandibular surgery. Prospective high-angle Class II patients should be comprehensively informed about the unpredictability of treatment outcomes in terms of occlusion and facial appearance., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Orthodontic Society.)

Background and Objectives: High-angle skeletal Class II malocclusion is one of the most challenging dentofacial deviations to treat and, in adults, a combination of orthodontic treatment and bimaxillary orthognathic surgery is often indicated. This study examines the rate of clinically significant relapse and whether a genioplasty affects the treatment outcome of high-angle Class II malocclusions., Material and Methods: Cephalometric tracings of 36 consecutively treated high-angle Class II patients were evaluated from pre-surgery to 3 years post-surgery. All patients had undergone bimaxillary surgery (Le Fort I and BSSO), 13 of them had in addition a genioplasty., Results: The maxilla remained stable, whereas relapse (greater than or equal to 2 mm) of the mandibular advancement was seen in 40 per cent of the patients. Advancement greater than 10 mm increased the risk for horizontal relapse. The overjet was normalized and remained stable despite mandibular relapse. Half of the patients had an anterior open bite 3 years post-surgery. A supplemental genioplasty did not affect the relapse rate., Conclusions and Implications: Overjet was normalized and remained stable long term; there was an open bite in half of the patients. Combined orthodontic and bimaxillary surgical treatment of high-angle Class II patients showed skeletal relapse (greater than or equal to 2 mm) of the mandible in 40 per cent of patients. Mandibular advancement greater than 10 mm increased the risk for relapse. There was no increased risk for dental or skeletal instability associated with a genioplasty in combination with maxillary and mandibular surgery in the treatment of high-angle skeletal Class II malocclusion., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Piezoelectric surgery is a newly introduced technique for rapid tooth movement. However, the efficiency of this technique has not been investigated on en-masse retraction cases yet., Objective: To investigate the efficiency of piezosurgery technique in accelerating miniscrew supported en-masse retraction and study the biological tissue response. In addition, to show if this technique induces a difference in dental, skeletal and soft tissue changes on lateral cephalograms, and in canine and molar rotations, besides intercanine and intermolar widths on dental casts., Design, Setting, Participants: We conducted a randomized, single-centred, parallel-group, controlled trial, requiring upper right and left first premolar extractions on 30 patients above the minimum age of 14 years at the beginning of retraction., Interventions: Piezosurgery-assisted versus conventional en-masse retraction anchored from miniscrews placed between second premolars and first molars, bilaterally., Outcomes: The main outcome was the en-masse retraction rate. Secondary outcomes were gingival crevicular fluid (GCF) volume and GCF content of receptor activator of nuclear factor κβ ligand (RANKL), changes regarding cephalometric and dental cast variables, and miniscrew success rates., Randomization: Accomplished with opaque, sealed envelopes., Blinding: Applicable for data assessment only., Recruitment: Commenced in February 2013 and ended in October 2014., Results: Thirty-one patients were included in the study and divided into 2 groups of piezosurgery (n = 16) and control (n = 15). After 9.3 months of follow-up, no statistically significant difference was observed between groups for neither retraction rates (P = 0.958) nor GCF parameters (P > 0.05). Changes in lateral cephalometric and dental cast variables, and miniscrew success rates did not show significant differences either., Conclusion: Based on the results of this study, piezosurgery technique was found to be ineffective in accelerating en-masse retraction, and promoting a difference in the studied GCF parameters, skeletal and dental variables., Registration: The trial was not registered., Protocol: The full protocol of this PhD thesis study can be accessed from tez.yok.gov.tr., Funding: This work was supported by Başkent University Research Fund. No conflict of interest was declared., (© The Author 2017. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com)

Background: Concerns about the effects caused by premolar extractions on the soft-tissue profile have motivated many investigations in different malocclusions., Objectives: To evaluate the cephalometric facial soft-tissue changes after orthodontic treatment with premolar extractions of Class II division 1 malocclusion subjects., Search Methods: Electronic databases PubMed, Web of Science, Embase, and Scopus were searched., Selection Criteria: Abstracts that appeared to fulfil the initial criteria (premolar extraction; cephalometric soft-tissue analyses/changes) were selected. The full-text original articles were then retrieved. Their references were also hand-searched., Data Collection and Analysis: By consensus of two researchers, the articles that fulfilled the selection criteria and quantified facial soft-tissue changes were individually analysed. Some methodological flaws were identified and some articles were excluded. The studies were rated according to the type of study, sample description and homogeneity, malocclusion severity, consideration of confounding factors, validity of the method, and statistical analyses., Results: Heterogeneous information about malocclusion severity before treatment was found in most articles. Statistically significant soft-tissue changes reported included nasolabial angle (NLA) increasing from 2.4 to 5.40degrees in 2-premolar extraction protocol and from 1 to 6.84degrees in 4-premolar extraction protocol. Retrusion of the upper and lower lips were also verified, with less retraction of the lower lip in 2-premolar extraction groups., Conclusions: When Class II division 1 malocclusion is treated with premolar extractions, the NLA increases and the lips are retracted. However, there is less retraction of the lower lip in the 2-maxillary premolar extraction protocol., (© The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objectives: This study aimed to assess whether non-extraction, two-premolars and four-premolars extraction Class II treatment protocols are different regarding long-term facial aesthetics, age appearance, and soft-tissue measures., Methods: Frontal and lateral photographs of 63 full Class II division 1 patients, treated at least 8 years before, were evaluated by 83 laypeople and 76 orthodontists, who assigned to each one's attractiveness scores from 1 to 10, and opined about their apparent ages. Patients were divided in three groups: XP0 (non-extraction, n = 20; 30.77 years, 15.63 years post-treatment), XP2 (two-premolars extractions, n = 25; 30.99 years, 15.68 years post-treatment), and XP4 (four-premolar extractions, n = 18; 32.80 years, 18.01 years post-treatment), that were matched by gender, post-treatment occlusal and soft-tissue outcomes, age, and post-treatment time. Soft-tissue measures were obtained with Dolphin Imaging 11.5 software., Results: Two-way analysis of variance revealed that attractiveness and apparent age were not affected by treatment protocols, but laypeople were slightly more critical then orthodontists. Analysis of variance showed more vertical facial pattern in XP4 group. Pearson correlation test revealed no influence of soft-tissue measures on sample's attractiveness., Conclusions: Treatment of full Class II division 1 malocclusion with and without extractions did not influence facial attractiveness, age appearance, and overall soft-tissue measures in the long-term., (© The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

To quantitatively evaluate on lateral cephalograms horizontal, vertical, and angular changes in the position of the maxillary first molar based on the presence and absence of erupted maxillary second molars when it is distalized with the XBow appliance. In this retrospective study, a total of 102 consecutively treated cases were assessed. Lateral cephalograms were obtained at the start and after completion of active treatment with the XBow appliance. In one group of patients, distal movement of the maxillary first molars was performed before the eruption of maxillary second molars; in the other group of patients, both first and second maxillary molars were simultaneously moved distally. All cephalograms were superimposed on palatal plane using the method of best-fit. In order to compare the mean horizontal, vertical, and angular changes in molar position between the treatment groups and gender, a multivariate analysis of covariance (MANCOVA) was performed with the pre-treatment class II severity used as a covariate. Regression analysis was also performed to further explore any possible relationships between the predictor variables and the quantity and quality of distalization. A MANCOVA revealed that the eruption stage of the maxillary second molar did not have a significant effect on the change in position of the maxillary first molar after treatment with a XBow appliance. When distalizing maxillary first molars with a XBow appliance, there is no difference in the amount of distalization in patients with erupted and unerupted maxillary second molars.

This study aimed to examine the skeletal, dental, and soft tissue effects of the implant-supported pendulum (ISP) and the zygoma anchorage system (ZAS) used for the distalization of maxillary posterior teeth. Among 30 patients showing Angle class II malocclusion, 15 patients with a mean age of 14.3±1.6 years and treated with ISP were included in the first group; 15 patients with a mean age of 14.7±2.5 years and treated with ZAS were included in the second group. The predistalization and postdistalization lateral cephalograms were analysed. Statistical evaluation was carried out using SPSS. Point A and upper incisors protruded in the ISP group, retruded in the ZAS group. Upper posterior teeth were distalized in both groups, but more in the ZAS group. Significant differences were observed between the groups for the sagittal movements of Point A, incisors, and posterior teeth. Overbite decreased in the ISP group, overjet decreased in the ZAS group, upper and lower lips retruded only in the ZAS group. Both methods provided absolute anchorage for distalization of posterior teeth, but the skeletal and soft tissue outcome and distalization obtained was greater in the ZAS group. Both methods can be used as alternatives to extraoral traction and conventional molar distalization appliances with different patient requirements.

The purpose of this study was to determine the perceived level of improvement in facial attractiveness as assessed by people with different backgrounds in skeletal Class II patients treated by mandibular advancement with bilateral sagittal split osteotomy (BSSO). The frontal and lateral pre- and post-operative photographs of 10 Caucasian patients were selected. Changes in frontal and profile attractiveness were assessed by 10 orthodontists, 10 art students, and 10 laypersons. Frontal and lateral pre- and post-operative photographs were randomly distributed throughout two surveys. For each photograph, the evaluators ranked the attractiveness of face, chin, and lips on visual analogue scales. A third survey was administered to orthodontists only, by presenting the same pre and post-operative photographs but paired side-by-side with pre- and post-operative status disclosed. Overall, attractiveness scores after BSSO showed an 11.5 per cent improvement (95 per cent confidence intervals: 9.4-13.5 per cent) on the lateral post-operative photographs and a 7.5 per cent improvement (95 per cent confidence intervals: 5.4-9.5 per cent) on the frontal post-operative photographs. Attractiveness scores differed significantly between the groups (P = 0.015), with orthodontists being more generous with their improvement ratings and the art students tending to give a more critical assessment. There were no significant differences between male and female evaluators (P > 0.05). Ratings of before-after attractiveness almost doubled when the pre- and post-operative status was disclosed as compared to blinded evaluations, thus indicating that prior knowledge of pre- and post-treatment status markedly influences aesthetic evaluations, with a bias towards a more favourable outcome.

Adult patients with a Class II skeletal base are often treated by a combined orthodontic and surgical approach. Advancement of the mandible, most often including a bilateral sagittal split osteotomy (BSSO), is preceded by orthodontic alignment and frequently the curve of Spee is levelled. When the chin is prominent, there is a risk of accentuating this as a result of surgery. An option to prevent this is to maintain a deep curve of Spee before surgical advancement. This will result in an opening rotation of the mandible during surgery and thus, a less prominent chin. The aim of this study was to compare, retrospectively, two orthodontic treatment approaches in patients treated by a BSSO. In one group (4 males, 20 females; mean age pre-surgery 29.3 years), the deep bite was maintained (deep bite group) while in the other (3 males, 10 females; mean age pre-surgery 27.1 years) the overbite was normal prior to surgery (level group). Lateral skull radiographs were taken before orthodontic treatment (T0), prior to surgery (T1), and at the end of treatment (T2). Differences between the groups as measured on lateral skull radiographs at T1 and T2 were analysed and quantified using an independent t-test. The results showed that soft tissue pogonion moved significantly further forward in the level than in the deep bite group (P < 0.05). Lower anterior face height and the cranial base-mandibular plane angle increased more in the deep bite than in the level group (P < 0.05 and P = 0.001, respectively). The maintenance of a deep bite prior to mandibular advancement surgery induces an opening rotation of the mandible reducing chin prominence and increasing lower anterior face height post-surgically.

Lateral head films of 200 Class II patients (106 females, 94 males) with a mean pre-treatment age range of 9.9-10.25 years successfully treated with functional orthodontics were analysed before (T1) and after (T2) treatment. The resulting data and findings were compared with lateral head films (T1, T2) of 20 patients (15 females, five males) with a mean pre-treatment age of 25.75 years whose Class II malocclusion and antero-posterior jaw discrepancy had been corrected by a mandibular sagittal split advancement osteotomy. The median and interquartile distances were calculated for every variable, at T1 and T2. The difference between the medians (T2-T1) was analysed using a signed rank test. The changes in scattering (T2-T1) were assessed by means of a F-test. Significant differences regarding the therapeutic influence on skeletal [ANB, Wits, Index, mandibular line-nasal line (ML-NL)], functional (beta', mu), and dental (1-NA degrees , 1-NB degrees ) variables were found. In the group initially treated with functional appliances in order to enhance mandibular prognathism, the antero-posterior (A-P) jaw discrepancy was reduced (ANB, Wits). The vertical skeletal pattern (Index) changed towards a more skeletal open relationship, whereas the ML-NL angle was reduced, which indicates a deepening of the bite. The comparison between biomechanical incisor position analysis (beta', mu) and dental variables (1-NA degrees , 1-NB degrees ) revealed different changes in incisor inclination depending on the type of analysis used. The findings for the dental variables (1-NA degrees , 1-NB degrees ) showed a protrusion of both upper and lower incisors after therapy. The results for the functional variables (beta', mu) showed a retrusion of the upper and a protrusion of the lower incisors. This change in incisor inclination is a dental compensation of the remaining sagittal jaw discrepancy. This effect is most clearly reflected by the functional analysis and the changes of the biomechanical variables beta' and mu. For the orthognathic surgery group, a clear improvement in the dental and skeletal relationship was observed: the skeletal discrepancies in the A-P plane were completely corrected (ANB, Wits) and the inclination of the incisors according to biomechanical and functional aspects was optimized (beta', mu).The alteration in both the Index and ML-NL angle in this group indicated an increase of the open bite components.

There are a number of increasingly sophisticated techniques available for orthognathic treatment planning. All are based on the determination of the skeletal pattern and the position of the dentition. However, they all suffer from difficulties associated with predicting the soft tissue profile. The aim of this retrospective cephalometric investigation was, therefore, to compare the ability to predict accurately the outcome of orthognathic treatment using the 'hand planning' technique and the orthognathic planning and analysis (OPAL) computer program, with an emphasis on the soft tissue profile. Seventy adult subjects were divided into two groups not specific for gender or age: the Class III patients had undergone bimaxillary surgery and the Class II patients sagittal split mandibular advancement. In each group, the pre-treatment and post-debond lateral cephalograms were utilized to calculate the actual orthodontic and surgical movements. These values were then used to produce a prediction using both the hand planning technique and the OPAL program. The resultant predictions were digitized using a customized computer program and compared with the actual outcome. The results show that there was marked individual variation when planning by hand and using the OPAL program. In the mandibular surgery group, hand planning and OPAL were of similar accuracy and few points differed significantly between prediction and outcome. However, for the bimaxillary group, a number of points showed bias and the hand planning technique appeared to be more accurate than the OPAL program, particularly in the region of the lips. Although the usefulness of predictions is acknowledged, these results suggest that they should be used with a certain amount of caution.

A case is described in which a Class II malocclusion with severe Class II skeletal pattern was treated with a modified Twin Block Appliance. The patient, an 11-year-old girl, had initially presented with an ameloblastoma located in the right maxilla. The subsequent defect produced by surgery was obturated by the appliance during her orthodontic treatment, which was undertaken during her pubertal growth spurt. Two years later the result was stable, allowing the provision of a more definitive prothesis to restore the occlusion.

The effect on distal molar occlusion following mandibular orthognathic surgery is highlighted. Two cases are presented in which at the completion of orthodontic/surgical treatment a stable molar occlusion was re-established by adjunctive restorative treatment. The clinical problem highlighted, illustrates the importance of restorative support for patients with residual post-orthodontic and post-surgical occlusal problems.

A case report is presented in order to illustrate the benefits of computerized video imaging in orthognathic surgery. It is suggested that superimposition of the cephalogram on the video image is helpful in treatment planning and in communication with the patient. Computerized video imaging techniques help clinicians and patients discuss the aesthetic impact of orthognathic surgery. The superimposition of the cephalogram and profile image, coupled with algorithmic predictions, allow the clinician to plan the surgery to closely match the desired result. This paper presents the planning and counselling of a patient using contemporary computerized video imaging techniques.

A longitudinal clinical-axiographic study including 10 patients who had undergone surgical mandibular advancement to correct a dental and skeletal Class II anomaly, produced evidence of correlations between alterations of acoustic symptoms and of mandibular mobility. In 7 of 11 movements, where TMJ-sounds disappeared, post-operative mandibular mobility was reduced to such a degree that the point at which the acoustic symptom originated pre-operatively could no longer be attained. On the other hand, in all cases, where TMJ sounds remained uninfluenced by the surgical intervention, reductions in mobility occurred only beyond this point. Even the persistence of losses of TMJ sounds during the further post-operative follow-up period could, in the majority of cases (4 of 7) be well explained by the persistence of mobility restriction. Accordingly, in the future a differentiation between mobility- and non-mobility-dependent alterations of TMJ symptoms should be made.

The three-dimensional changes in the bone and the ratio of soft tissue to bone movement were investigated in a group of 17 Skeletal II patients following orthognathic surgery. CT scans were taken for each patient pre-operatively and 1 year post-operatively. The scans were superimposed, radial measurements calculated, and the changes illustrated by two separate colour scales. There was a constant ratio of movement over the maxillae with the central part of the upper lip being moved in a 1:1 ratio, increasing to a 1.25:1 ratio over the canine regions and 1.5:1 ratio over the paranasal areas. In the mandible there was a constant ratio of 1.25:1 over the chin, mentalis, and canine regions bilaterally. The ratio reduced to 1:1 over the body of the mandible.

A prospective study including 63 adult Class II and Class III patients was carried out in order to examine short- and long-term effects of four different treatment methods on mandibular mobility. The patients were treated either (Group A, control-group) orthodontically alone or (Group B) by a LeFort I-osteotomy, a (Group C) mandibular advancement or (Group D) a two-jaw surgery/mandibular set-back. In the surgery-groups (B, C, and D) maximum opening, protrusion and lateral excursions were measured 2 days pre-operatively (T0), and 3, 8, 14.5, and 25.5 months post-operatively (T1-T4). In the control-group (A) at T0 and T4 was measured, only. Significantly differing effects of the four treatment methods on mandibular mobility were detected. (A) Orthodontic treatment alone, (B) maxillary advancement by LeFort I osteotomy, and (D) two-jaw surgery/mandibular set-back osteotomy did not influence mandibular mobility permanently. Temporary decreases in groups B and D (P less than or equal to 0.05) were observed, however. In contrast, permanent reductions after (C) mandibular advancement took place (P less than or equal to 0.001). Longitudinal survey showed that in all surgery groups recoveries were limited to a short period of 3-14.5 months, depending on the movement. Surprisingly, a closer similarity between the LeFort-I group (B) and the two-jaw surgery group (D), rather than between the sagittal-split groups (C and D), was seen indicating that the problem of reduced mobility after orthognathic surgery can be limited to Class II therapy. It was concluded that in Class III therapy, the application of rigid fixation in combination with a method of maintaining condyle-position, thereby dispensing with maxillomandibular fixation, prevents permanent reductions in mobility and guarantees a rapid recovery to pre-operative mobility levels.

The surgical correction of eleven Class III patients and 10 Class II patients with a long face, increased maxillary mandibular planes angle and anterior open bite was undertaken using bimaxillary surgical procedures. Lateral skull radiographs were examined pre-operatively, 48 hours, and 1 year post-operatively, to quantify the amount and direction of surgical change achieved and the subsequent stability. There was no consistent pattern in the actual movements achieved in either group of patients in the maxillae or the mandibles. Some of the cases being impacted and continuing to impact, others impacting then relapsing. In the Class III patients some of the mandibular set backs remained stable others relapsing and some continuing to move posteriorly. However, despite these inconsistent patterns, there was a 7-degree reduction in the maxillary mandibular planes angle which relapsed by 1.7 degrees over the first year. The overbite was increased from -6 mm to +3.1 mm post-operatively and this relapsed at the 1 year stage to +2.4 mm. The overjet reduced from -4 to 1.7 mm and continued to improve to -0.9 mm at the 1-year stage. In the Class II patients some of the mandibular advancements remained stable others relapsing and some continuing to advance. However, despite these inconsistent patterns there was a 9-degree reduction in the maxillary mandibular planes angle which reduced by a further degree at the 1 year stage. The overbite was increased from -4.6 to -1.6 mm post-operatively and this remained stable at the 1 year stage.(ABSTRACT TRUNCATED AT 250 WORDS)

Many attempts have been made to measure and compare the changes in the facial surface brought about by facial reconstructive surgery. Three-dimensional (3-D) analyses have largely consisted of qualitative descriptions rather than a quantitative treatment of these changes. Until recently, the lack of availability of 3-D data for the face and head has limited the advancement of these techniques. However, with 3-D information readily available from a laser scanning system which we have constructed, a technique has been applied which describes mathematically the facial shape and changes occurring in the face in terms of fundamental surface types. The method is described and used to compare the faces of two patients (one a cleft palate patient and the other a long-face, Class II malocclusion patient) before and after surgery along with the clinical description of the surgery, the resulting facial changes, the actual surgery performed, and the predicted surgical expectation. A strong relationship is found between the surface type description and the clinical observations. The implications of the method for surgery, facial aesthetics, and other disciplines are discussed.

The planning and management of orthodontic treatment for patients requiring surgery is considered in the light of a variety of problems that occur commonly, but have not received much attention in the literature. These problems can be categorized into dental, skeletal, and soft tissue varieties, and some cases are presented in illustration. The occasional need for compromise in treatment planning is suggested and the limitations of an excessive dependence on cephalometrics are discussed.

Orthodontic treatment decisions when maxillary central incisors are absent or are of poor prognosis, are discussed. Autotransplantation of mandibular first premolars to the incisor region is suggested as an approach in selected cases. The literature is reviewed, surgical technique described and case selection summarized. Cases are reported where autotransplantation of premolars to the maxillary incisor region has produced good functional and aesthetic results.

A 17-year-old male presented with bilateral double teeth in the 2 2 region and upper arch crowding. These were surgically sectioned and orthodontic treatment carried out to align 321 123. The sectioned teeth remained vital.

In 31 surgically treated Class II patients, several features were studied on cephalograms, before and after a mandibular lengthening osteotomy had been performed. After surgery, hardly any changes in the soft tissue thickness were recorded. In Class II patients, the upper part of the lower lip is situated at a larger distance from the skull, since its position is influenced by the antero-posterior position of the upper incisors and the overjet. The postoperative decrease of this distance was caused by the fact that the upper part of the lower lip failed to follow the total amount of forward mandibular displacement. This is due to the fact that the antero-posterior position of this part of the lip is touching the upper incisors and therefore does not follow the amount of mandibular advancement. The labiomental fold flattens, because the lower part of the lower lip completely follows the forward displacement of the mandible, whereas the upper part remains almost unchanged. This flattening can be favourable in Class II patients showing a very deep fold, as the surgical intervention tends to normalize the depth. In open bite profiles on the contrary, this effect could be unfavourable. The combination of the lengthening osteotomy with a genioplastic intervention, could mask this unfortunate result. Due probably to the presence of orthodontic retention devices and the intercuspidation of teeth, normal occlusal relations remained one year after surgery. A relapse of about 30 per cent was found in the mandibular bases. In order to anticipate this, some surgical overcorrection could be considered.