Skeletal anchorage for orthodontic correction of severe maxillary protrusion after previous orthodontic treatment

The correction of a severe maxillary protrusion in an adult by distal movement of the maxillary molars has been one of the most difficult biomechanical problems in orthodontics. This article reports on the treatment of an adult case of severe maxillary protrusion and a large overjet treated with a skeletal anchorage system. A female patient, age 22 years and 3 months, complained of the difficulty of lip closure due to severe maxillary protrusion with a gummy smile. Overjet and overbite were +7.6 mm and -0.9 mm, respectively. She had a history of orthodontic treatment in which her maxillary first premolars were extracted. In order to conduct distal movement of the maxillary molars, anchor plates were placed in the zygomatic process. After achieving a Class I molar relationship, retraction and intrusion of the maxillary incisors were performed. After a 2-year treatment, an acceptable occlusion was achieved with a Class I molar relationship. Her convex facial profile with upper lip protrusion was considerably improved, and the lips showed less tension in lip closure. After a 2-year retention period, an acceptable occlusion was maintained without recurrence of maxillary protrusion, indicating a stability of the occlusion. The result of this treatment indicated that skeletal anchorage is of great importance as a remedy for achieving intrusion and retraction of the maxillary incisors in cases of severe maxillary protrusion with a patient who had previous orthodontic treatment.     

Effects of a three-dimensional bimetric maxillary distalizing arch

This study aimed to investigate the dental effects of a three-dimensional (3D) bimetric maxillary distalizing arch. The Wilson rapid molar distalization appliance for Class II molar correction was used in 14 patients (10 girls and four boys with a mean age of 12.18 years). The open coil springs were activated with bent Omega stops and Class II intermaxillary elastics. The mandibular anchorage was gained by a 0.016 x 0.016 utility arch with a 3D lingual arch or a lip bumper with a standard lingual arch. The lateral cephalograms taken before and after treatment formed the material of the research. A Wilcoxon test was used to statistically evaluate the treatment effects. The results showed that the distal tipping of the maxillary first and second molars, and first and second premolars and canines were statistically significant. Significant distal movement occurred in all posterior and canine teeth. The maxillary first molar distalization was found to be 3.5 mm. The maxillary incisor showed significant proclination and protrusion. The decrease in overbite was found to be statistically significant. The mandibular plane angle significantly increased by a mean of 0.5 mm. In addition, significant soft tissue changes were observed.     

Evaluation of the Jones jig appliance for distal molar movement.

The purpose of this study was to determine the effects of the Jones jig appliance on distal movement of maxillary molars and reciprocal effects on premolars and maxillary incisors. Cephalometric radiographs before and after orthodontic treatment of 72 consecutively treated patients, 46 females and 26 males, were measured to define treatment changes attributed to the Jones jig. Comparative measurements were made on a matched sample of 35 patients (20 females and 15 males) treated with cervical headgear by the same clinician. Both series of patients were treated to correct an Angle Class II molar relationship. The molar correction in the Jones jig patients consisted primarily of molar distal movement. Dental, soft tissue, and skeletal changes were evaluated and compared for significant differences between techniques. The results from the Jones jig sample showed the mean maxillary first molar distal movement was 2.51 mm, with distal tipping of 7.53 degrees. The mean reciprocal mesial movement of the maxillary premolar was 2.0 mm, with mesial tipping of 4.76 degrees. The maxillary first molar extruded 0.14 mm; the maxillary premolar extruded 1.88 mm. The maxillary second molars were also moved distally 2.02 mm and tipped distally 7.89 degrees. The longitudinal assessment (initial to completion of orthodontic treatment) showed significant differences between the Jones jig sample and the cervical headgear sample for lower lip to E-line and SNA. The Jones jig sample showed a mean decrease in lower lip to E-line of 0.25 mm versus 1.20 mm (P < .0212) for the headgear sample. SNA decreased 0.40 degrees for the Jones jig sample versus 1.20 degrees (P < .0093) for the headgear sample. However, the Jones jig sample and cervical headgear sample did not show significant differences of the final position in either linear or angular measurements of the maxillary first molars and corresponding premolar-incisor anchor units. The Jones jig appliance demonstrated treatment results comparable with those of the sample treated with cervical headgear. The Jones jig sample demonstrated effective distal molar movement and maintenance of the Class I molar relationship. Advantages of the Jones jig include minimal dependence on patient compliance, ease of fabrication, and ease of buccal force application.     

Cephalometric Changes following Simultaneous First and Second Maxillary Molar Distalization Using a Non-Compliance Intraoral Appliance

AIM: The aim of this prospective study was to evaluate the dentoalveolar, skeletal and soft tissue changes induced by a modified minimal-compliance intraoral appliance following the simultaneous distalization of first and second maxillary molars. SUBJECTS AND METHODS: The study sample consisted of 14 patients with a mean age of 13.4 years treated by one clinician. In all cases a bilateral Class II molar relationship was corrected to Class I in a mean treatment period of 16.5 weeks. Lateral cephalometric analysis of the sample was based on the radiographs taken before and immediately after treatment with the appliance. The mean maxillary first molar distal movement was 1.4 mm, accompanied by a mean distal tipping of 6.8 degrees. The vertical change in molar position was insignificant. The anchorage unit was unable to completely resist the reciprocal mesial force of the activated coil spring. The second premolars were moved mesially by a mean 2.6 mm and tipped by a mean 4.1 degrees without significant extrusion. The mean increase in overjet was 0.9 mm, and the mean decrease in overbite 1.0 mm. RESULTS: The results of this study have shown that the presented intraoral appliance is an effective and reliable means of distalizing first and second maxillary molars simultaneously without the need for patient compliance. Appliance effects are limited primarily to the dentoalveolar structures. Mesial movement and slight protrusion of the anchorage unit have to be taken seriously into consideration during intraoral distalization.     

Maxillary unilateral molar distalization with sliding mechanics: a preliminary investigation.

Fifteen patients, eight males and seven females with a mean age of 13.32 years, were selected for unilateral molar distalization. Dentally, all presented with a unilateral Class II molar relationship. The subjects were all in the permanent dentition with second molars erupted and with a well aligned lower dental arch. For maxillary molar distalization a new intra-oral appliance was developed, the Keles Slider, which comprised two premolar and two molar bands. The anchorage unit was a Nance button with an anterior bite plane. From the palatal side, the point of distal force application was carried towards the level of centre of resistance of the maxillary first molar. A Ni-Ti coil spring was used and 200 g distal force was applied to the Class II first molar. Lateral cephalograms were taken and analysed before and 2 months after molar distalization. The Class II molars were distalized bodily, on average, 4.9 mm (P < 0.001). Mesial migration of the Class II first premolars was 1.3 mm (P < 0.05), incisor protrusion was 1.8 mm (P < 0.05) and incisor proclination 3.2 degrees (P < 0.05). The overbite was reduced by 3.1 mm (P < 0.001) and the overjet increased 2.1 mm (P < 0.01). For stabilization, the corrected Class II unilateral molar relationship was maintained with a Nance button for 2 months. The results show that this newly developed device achieved bodily distal molar movement with minimum anchorage loss.     

Unilateral molar distalization with a modified slider

Although there are numerous publications on bilateral non-compliance molar distalization appliances, there is limited information on problems such as asymmetrical unilateral Class II malocclusions. The aim of the present investigation was to examine the distalization of molars unilaterally in patients with a unilateral Class II molar relationship utilizing a Keles Slider, designed without a bite plane. Ten girls (mean age 13.94 +/- 2.13 years) and seven boys (mean age 13.12 +/- 1.51 years) comprised the study material. Following insertion of the appliance, the patients were seen monthly and the screw was reactivated every 2 months. After a super-Class I molar relationship was achieved, the appliance was removed and the molars were stabilized with a Nance appliance for 2 months before the second-phase of orthodontic treatment. The Nance appliance was maintained in the palate until the end of canine distalization. Lateral cephalometric radiographs were obtained before and immediately after insertion of the molar distalizer. The results showed that the maxillary first molars were distalized bodily on average by 2.85 mm. The maxillary first premolars moved forward bodily 2 mm and were extruded 2.03 mm. In all, 1.32 mm of protrusion, 1.12 mm of extrusion, and 1.79 degrees of proclination of the upper incisors were observed. The mandibular incisors and mandibular molars erupted 0.83 and 0.95 mm, respectively. The unilateral Keles Slider distalized molars successfully to a Class I molar relationship.     

上下颌唇挡对替牙晚期儿童牙(牙合)的影响

目的研究上下颌唇挡同时应用对替牙晚期儿童牙(牙合)的影响.方法选择替牙晚期上下牙列轻度或中度拥挤患儿12例,上下颌均采用唇挡治疗8个月,进行治疗前后X线头影测量分析和模型测量分析,并对治疗前后的测量值变化进行配对t检验.结果唇挡治疗后,SNA、SNB分别增加1.02°和0.97°(P＜0.05),上下切牙前移均是牙冠向近中倾斜,而根尖相对固定的控制性倾斜,旋转中心接近根尖.上下磨牙远中倾斜效果不同,上磨牙远中倾斜直立,旋转中心接近牙冠;下磨牙远中倾斜移动,旋转中心接近阻抗中心;上颌磨牙间牙弓宽度、牙弓周径分别增加4.12mm和5.09mm(P＜0.01),下颌磨牙间牙弓宽度、牙弓周径分别增加4.07mm和6.86mm(P＜0.01).结论在儿童生长发育高峰期,唇挡可有效地引起上下颌牙弓横向和纵向变化,减轻或解除上下牙弓拥挤.     

A new approach in maxillary molar distalization: intraoral bodily molar distalizer.

The objectives of our study were to achieve bodily molar distalization, avoid distal tipping of molars, eliminate the need for patient cooperation (no headgear, no elastics, and no esthetic and social concern), and finally to minimize the treatment period and maximize the treatment efficiency. The study was carried out on 5 males and 10 females, a total of 15 patients. Mean age for the study group was 13.53 years. Dentally, all the patients had Class II molar relationship on both sides. The patients were in permanent dentition, second molars were erupted, and the lower dental arch was well aligned. Patients showed normal or sagittally directed growth pattern. Lateral cephalograms and study models were taken and analyzed before and after molar distalization. In the present study, in order to achieve maxillary molar distalization, a new intraoral appliance was developed. The intraoral bodily molar distalizer (IBMB) was composed of 2 parts: the anchorage unit and the distalizing unit. The anchorage unit was a wide Nance button, and the active unit consisted of distalizing springs. The springs had 2 components: the distalizer section of the spring applied a crown tipping force, while the uprighting section of the spring applied a root uprighting force on the first molars. A total of 230 g of distalizing force was used on both sides. After the distal movement of the first molars, the cephalometric results of 15 patients showed the following. Maxillary first molars were moved distally by an average of 5.23 mm (P <.001) without tipping or extrusion. Maxillary first premolars were moved 4.33 mm mesially (P <.001), tipped 2.73 degrees distally (P <.05), and extruded by 3.33 mm (P <.001). Maxillary central incisors were proclined by an average of 4.7 mm (P <.001) and tipped 6.73 degrees labially (P <.01). Model analysis showed that maxillary first molars were not rotated, and intermolar distance did not change after distal movement of molars. In conclusion, unlike most of the other molar distalization mechanics, this newly developed device achieved (1) bodily distal movement of maxillary molars and (2) eliminated dependence on patient cooperation and did not require headgear wear for molar root uprighting.     

The effect of a maxillary lip bumper on tooth positions

The effect of the use of a lip bumper with anterior vestibular shields on the maxilla was studied in twenty-two 9-14-year-old children with a space deficiency in the maxillary dental arch. The lip bumper was used for 1 year. The effect of the treatment was evaluated from dental casts and profile cephalograms made before and after treatment. Both the width of the maxillary dental arch at the premolars and the length of the arch increased significantly by about 2 mm. The effect of the treatment on the antero-posterior position of the first molars was small. In one subject the molar was distalized 2.8 mm. The average effect was, however, a reduction in the anterior movement of the molar within the face by about 0.5 mm, i.e. the maxilla moved anteriorly 1 mm, but the molar only 0.4 mm. No skeletal effects were found when the group of subjects treated with a lip bumper was compared with a reference sample of untreated individuals. The main effects of a maxillary lip bumper thus seem to be a widening of the dental arch across the premolars, a moderate increase in arch length due to eruption and slight proclination of the incisors, and moderate distal tipping of the first molars.     

A strategy for nonextraction class II treatment

Class II nonextraction treatment, which commonly includes distal movement of the maxillary molars to correct the molar relationship, most often can be successful when treatment is started in the late-mixed dentition stage of development. At least two factors contribute to this success. One is that the molars can be distalized routinely at this age. The second is that the “E” space is available and can be used either to help correct the molar relationship or to resolve any crowding that may exist. This article describes and illustrates the treatment of a late mixed-dentition patient with this type of Class II nonextraction treatment that includes distal movement of the maxillary molars with a 100 g NiTi coil system and the maintenance of the “E” space with a lip bumper.     

Dentoalveolar and skeletal changes associated with the pendulum appliance.

The purpose of the study was to examine the dentoalveolar and skeletal effects of the pendulum appliance in Class II patients at varying stages of dental development and with varying facial patterns (high, neutral, and low mandibular plane angles). Specifically, the amount and nature of the "distalization" of the maxillary first molars and the reciprocal effects on the anchoring maxillary first premolars and incisors were studied, as were skeletal changes in the sagittal and vertical dimensions of the face. Pretreatment and posttreatment cephalometric radiographs obtained from 13 practitioners were used to document the treatment of 101 patients (45 boys and 56 girls). The average maxillary first molar distalization was 5.7 mm, with a distal tipping of 10.6 degrees. The anchoring anterior teeth moved mesially, as indicated by the 1.8-mm anterior movement of the upper first premolars, with a mesial tipping of 1.5 degrees. The maxillary first molars intruded 0.7 mm, and the first premolars extruded 1.0 mm. Lower anterior facial height increased 2.2 mm; there was no significant difference in lower anterior facial height increase between patients of high, neutral, or low mandibular plane angles. In patients with erupted maxillary second molars, there was a slightly greater increase in lower anterior face height and in the mandibular plane angle and a slightly greater decrease in overbite in comparison to patients with unerupted second molars. Similar findings were observed in patients with second premolar anchorage versus those with second deciduous molar anchorage. The results of this study suggest that the pendulum appliance is effective in moving maxillary molars posteriorly during orthodontic treatment. For maximum maxillary first molar distalization with minimal increase in lower anterior facial height, this appliance is used most effectively in patients with deciduous maxillary second molars for anchorage and unerupted permanent maxillary second molars, although significant bite opening was not a concern in any patient in this study.     

微螺钉种植体支抗推磨牙向后的临床研究

目的研究临床上微螺钉种植体作为强支抗在推磨牙向远中的治疗效果。方法选取10例AngleⅡ类重度拥挤的患者作为研究对象,采用双侧颊侧植入微螺钉种植体作为强支抗远移上颌磨牙,施力为2.45～2.94N。在治疗前后拍摄头颅侧位片,测量上颌第一磨牙在矢状向的位置变化。取研究模型,通过三维扫描仪及测量软件测量上颌磨牙的三维方向的变化,进行统计学分析。结果所有病例都达到了预期的矫治效果,磨牙中性关系、面型得到了较好的改善。上颌第一磨牙平均向远中移动3.58±0.87mm;上颌磨牙的压低、颊倾、远中倾斜治疗前后均无显著性差异。结论微螺钉种植体作为强支抗,能成功远移上颌磨牙,没有出现支抗丧失,是非常有效的非依从性远移磨牙的方法。     

微种植体支抗钉结合改良滑动杆近中移动 上颌前磨牙的临床应用

目的 探讨微种植体支抗钉结合改良滑动杆近中移动上颌前磨牙关闭缺牙间隙的可行性及有效性。方法 选取上颌侧切牙或尖牙缺失的患者5例（男2例,女3例）,年龄14~25岁。缺失侧磨牙关系均为安氏Ⅱ类。在上颌第二前磨牙及第一磨牙间植入微种植体支抗钉,结合改良滑动杆近中移动前磨牙。前磨牙移动到位后更换支抗钉位置,利用支抗钉拉磨牙近中移动,关闭剩余间隙。前磨牙移动疗程6~10个月。通过矫治前后石膏模型测量前磨牙近中移动有效性。结果 5例患者均得到有效治疗,上颌前磨牙及磨牙近中移动,缺牙间隙关闭,缺牙侧磨牙关系完全远中,治疗效果均令人满意。上颌前磨牙近中平均移动4.1 mm,平均移动速度0.96 mm/月。结论 对于上颌侧切牙或尖牙缺失的患者,微种植体支抗钉结合改良滑动杆可简单高效实现前磨牙近中移动,并最终关闭缺牙间隙,临床上可作为一种备选治疗方案。     

Dentoskeletal effects induced by rapid molar distalization with the first class appliance.

The purpose of this study was to evaluate the treatment effects of the first class appliance (FCA; Leone, Firenze, Italy), a new intraoral device for unilateral or bilateral rapid molar distalizaton. A retrospective study was conducted to compare the predistalization and postdistalization cephalograms of 17 patients (10 male, 7 female) with Class II malocclusions treated with the FCA. Mean age at the start of treatment was 13 years 4 months. The FCA produced rapid molar distalization, and the bilateral Class II molar relationship was corrected in 2.4 months, on average. Maxillary molar distalization contributed to 70% of the space created anterior to the first molars; 30% of the space was due to reciprocal anchorage loss of the maxillary second premolars. The maxillary first molars showed a significant distalization of 4.0 mm, associated with a significant distal axial incline of 4.6 degrees and a significant extrusion of 1.2 mm. As for anchorage loss, the second premolars exhibited a significant mesial movement of 1.7 mm, associated with a significant mesial axial incline of 2.2 degrees and a nonsignificant extrusion of 1.0 mm. In the anterior region, a significant mesial movement of the maxillary incisor of 1.3 mm was associated with a significant incisor proclination (2.6 degrees ) and a significant increase in overjet (1.2 mm). No significant changes in either sagittal or vertical skeletal relationships were observed. The results suggest that the FCA is an efficient and reliable device for distalizing the maxillary permanent first molars.     

Combined use of miniscrews and continuous arch for intrusive root movement of incisors in Class II division 2 with gummy smile

Adequate intrusion and torque control of the retroclined maxillary incisors are critical for the treatment of Class II division 2 (div2) malocclusion. In addition, anterior retraction via lingual root movement can be challenging. This case report demonstrates a combined use of miniscrews and continuous arch with additional torque for intrusion, retraction, and torque control of maxillary incisors in the Class II div2 with gummy smile. A 20-year-old woman presented with multiple issues, including impacted canine, lip protrusion, prolonged retained mandibular primary molar, and two missing maxillary premolars. In order to improve her facial profile and eliminate the need for prosthetic work, the mandibular primary molar and contralateral premolar were extracted. Two miniscrews were placed at the maxillary buccal alveolar bone to apply the posterosuperior force for retraction of anterior teeth, with additional labial crown torque on the arch wire. The results were the intrusion (4 mm) and lingual root movement (17°) of the maxillary incisors without anchorage loss of maxillary molars, flattening of the Curve of Spee, and Class I molar relation that were maintained after 50 months of retention period. The combined use of miniscrews and continuous arch could be a reliable and effective treatment modality for torque control and intrusion of retroclined maxillary incisors in the Class II div2 patient.     

Asymmetric severe skeletal Class II division 1 patient with temporomandibular joint disorder treated with zygomatic anchorage devices and Ni-Ti alloy wires

Objective:To describe the orthodontic treatment of a nongrowing 30-year-old woman with asymmetric severe skeletal Class II malocclusions (asymmetric Angle Class II), large overjet (16 mm), large overbite (8 mm), two congenitally missing mandibular incisors (presenting a deciduous anterior tooth), and signs and symptoms of temporomandibular joint disorder (TMD).Materials and Methods:We used novel improved super-elastic Ni-Ti alloy wires (ISWs) combined with Ni-Ti alloy coil springs, power hooks, and a zygomatic implant as reinforced anchorage to provide a constant and continuous mild force to the dentition.Results:We successfully distalized maxillary molars, premolars, and retracted anterior teeth and corrected the asymmetric Angle Class II molar relationship using this system of zygomatic anchorage in conjunction with ISWs, Ni-Ti alloy open-coil springs, and crimpable power hook. The maxillary molars were distalized, and postero-occlusal relationships were improved to achieve Class I canine and molar relationships on both sides. Intrusion of the upper molars made the mandibular plane close. Ideal overbite and overjet relationships were established. Facial esthetics were improved with decreased upper and lower lip protrusion, and no symptoms of TMD were observed after treatment.Conclusion:The orthodontic treatment described here is a promising anchorage technique alternative to traditional techniques to improve severe skeletal Class II with TMD.     

Class II division 1 malocclusion treated with extraction of upper first premolars: Case report

This report describes the treatment of a 13.7-year-old girl with a severe maxillary protrusion. She indicated Class II molar and canine relationship and showed 7-mm overjet, 0-mm overbite, and slight lower midline deviation with an unstable mandibular position. Treatment was started using a splint to stabilize the position of the mandible, followed by extractions of maxillary first premolars and fixed appliances to reduce lip protrusion. Molars were finished in a Class II relationship with canine guidance, and ideal overjet and overbite relationships were established. Also the final result was esthetically well balanced. The treatment results were stable 6 years after debonding.     

Extraction treatment of a Class II division 2 malocclusion with mandibular posterior discrepancy and changes in stomatognathic function

This case report describes the successful extraction treatment of a Class II division 2 malocclusion with mandibular posterior discrepancy and a congenitally missing maxillary lateral incisor on the left side. The posterior space in the mandibular arch was small, and the mandibular second molars were impacted, with distal tipping. The discrepancies in the maxillary and mandibular arches were resolved by extraction of the maxillary lateral incisor on the right side and the mandibular second premolars on both sides. The mesial movement of the mandibular first molars occurred appropriately, with the second molars moving into an upright position. A lip bumper was used with a preadjusted edgewise appliance in the maxillary dentition to reinforce molar anchorage and labial movement of the retroclined incisors. Despite the extraction treatment, a deep bite could be corrected without aggravation as a result of the lip bumper and utility arch in the mandibular dentition. Thus, an Angle Class I molar relationship and an ideal overbite were achieved. The occlusal contact area and masticatory muscle activities during maximum clenching increased after treatment. The maximum closing velocity and the maximum gape during chewing increased, and the chewing pattern changed from the chopping to grinding type. The findings in the present case suggest that the correction of a deep bite might be effective for improving stomatognathic function.     

Combined orthodontic and surgical treatment of severe mandibular laterognathie with bimaxillary protrusion: case report

This article summarizes the treatment progress for a patient with a severe dolichofacial pattern with a convex profile, severe lip incompetency, and concomitant mouth breathing. Her maxillary occlusal plane had a cant and the maxillary and mandibular midlines were shifted 2 and 4 mm to the left side, respectively. The treatment plan summary was as follows: (1) maxillary rapid expansion for the elimination of maxillary constriction; (2) extraction of maxillary right first molar; (3) extraction of mandibular first premolars; (4) preoperative orthodontic treatment to correct dental protrusions; (5) surgical repositioning of the maxilla and mandible; and (6) postoperative orthodontic treatment and retention. Orthodontic treatment lasted a total of 28 months, with a good intercuspation and significantly improved facial esthetics at the end of treatment. The 1-year postretention lateral cephalometric measurements did not indicate any significant relapse. Dental protrusion and crowding in both jaws were eliminated. Facial and dental asymmetry was resolved and the profile was improved. The cant of the occlusal plane and the lips were corrected. Evaluation of pre- and posttreatment profiles revealed a decrease in convexity. Dentally, Class I canine and Class III molar relationships were present at the end of the treatment. Maxillary and mandibular incisors were uprighted, improving the interincisal angle and the bite relationship.     

Severe unilateral scissor bite and bimaxillary protrusion treated by horseshoe Le Fort I osteotomy combined with mid-alveolar osteotomy

This report describes an orthognathic surgical case employing horseshoe Le Fort I osteotomy (HLFO) combined with mid-alveolar osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) for a patient with severe unilateral scissor bite and bimaxillary protrusion. A female patient (aged 26 years, 2 months) presented with a chief complaint of dysmasesis caused by scissor bite on the right side. The clinical examination revealed difficulty in lip closure and a convex profile. Overerupted right maxillary premolars and molars and lingual tipping of the right mandibular premolars and molars were indicated before treatment. After 3 months of presurgical orthodontic treatment, two-jaw surgery involving a combination of HLFO with mid-alveolar osteotomy and BSSRO was performed. A good interdigitation in the right side was established by superior-posterior-medial movement of the dento-alveolar segment of the maxilla. Next, both the maxilla and mandible were moved superiorly and posteriorly to correct the improper lip protrusion, thereby improving the patient''s profile. Our results suggest that this new orthognathic surgery technique—achieved by combining HLFO with mid-alveolar osteotomy and BSSRO—is effective for adult patients exhibiting severe unilateral scissor bite and bimaxillary protrusion.