Collaborative treatment for a case of condylar hyperplastic facial asymmetry

Facial asymmetry can be caused by unilateral condylar hyperplasia. In such cases, it may be difficult to achieve symmetry since there is dentoalveolar compensation on the affected side, and the occlusal cant does not correspond to the frontal mandibular deviation. In the case presented, surgical orthodontic treatment and orthognathic surgery planning was accomplished for a patient with facial asymmetry due to condylar hyperplasia. The surgical plan was devised with particular attention to the severe dentoalveolar compensation. In this case, prior to the two-jaw surgery, the occlusal cant and frontal mandibular plane inclination was corrected through impaction of the left molar region by segmental osteotomy. Facial asymmetry and severe dentoalveolar compensation were successfully corrected after a unilateral segmental osteotomy and two-jaw surgery, resulting in a stable occlusal relationship and facial symmetry as well as good jaw function. Collaboration between the orthodontists and maxillofacial surgeons was essential for the successful treatment of the patient.     

Le Fort I截骨术治疗上颌骨折咬合错乱

目的根据正颌外科技术要点,应用模型外科、Le Fort I型截骨术及钛板坚固内固定治疗上颌骨折移位咬合错乱.方法笔者经治的颌面部骨折患者8例,取模型按模型外科设计骨切开线,制作咬合板并行单颌牙弓夹板预备.采用Le Fort I型截骨恢复咬合关系后行坚固内固定.结果所有病例均为一期愈合,7例术后咬合关系恢复良好,2例术后开口度明显改善,其余病例开口度恢复正常.颜面外形恢复良好.结论按模型外科设计,行Le Fort I型截骨术是矫治上颌骨折咬合紊乱较为理想的方法,咬合板有利于(牙合)关系的恢复和稳定.     

Orthognathic surgery in craniomaxillofacial fibrous dysplasia.

In craniomaxillofacial fibrous dysplasia, jaw involvement often causes facial asymmetry, an occlusal cant, and loss of teeth. Although conservative management of fibrous dysplasia affecting the jaws is widely practiced, orthognathic surgery is indicated in such cases to restore occlusion and correct dentofacial deformity brought on by the disease process. Since 1981, the Craniofacial Center at Chang Gung Memorial Hospital in Taiwan has treated a total of 84 patients with craniomaxillofacial fibrous dysplasia. Of these, 55 (65%) had fibrous dysplasia affecting the jaws (Zone 4). Between 1988 and 1997, orthognathic surgery was performed on 1 male and 4 female patients with fibrous dysplasia involving the teeth-bearing jaws. One patient had localized fibrous dysplasia that involved the mandible. The other 4 patients had polyostotic craniofacial involvement of Zones 1, 2, or 3 and 4A. The patient with isolated mandibular involvement and 2 patients with maxillary fibrous dysplasia had single-jaw surgery. The other 2 patients with maxillary involvement required simultaneous two-jaw surgery to correct the dentofacial deformities resulting from the disease process. Follow-up ranged from 12 months to 9 years. All the patients had stable occlusion, good facial aesthetics, and no further recurrence after surgery. The long-term stability of the achieved occlusion and facial appearance confirms that adequate healing in fibrodysplastic bone is to be expected using the standard fixation.     

Dynamic orthognathic surgical procedure (DOSP) in asymmetric maxillomandibular dysmorphism secondary to unilateral micrognathia: Outcomes of 12 consecutive cases

This study aimed to evaluate the outcomes following a dynamic orthognathic surgical procedure performed at the end of growth to treat asymmetric maxillomandibular deformities linked to unilateral micrognathia when conventional orthognathic surgery was not feasible.The dynamic orthognathic surgical procedure (DOSP) combined concomitant mandibular distraction osteogenesis with contralateral poorly stabilized sagittal split osteotomy and Le Fort I osteotomy. Cephalometric studies were retrospectively conducted on pre- and postoperative lateral and frontal cephalographs, and maxillomandibular movements were calculated. Outcome scores were computed by both experts and laypersons based on photographic analyses.There was a significant postoperative increase in height of the micrognathic ramus in all patients (n = 12; p = 0.002). The angle between the occlusal cant and horizontal reference plane decreased significantly in all of the patients, as did the angle between the midline sagittal plane and mandibular tilt (p < 0.001). Postoperative outcome scores showed significant improvements in all cases, according to both expert and layperson groups.This procedure allows correction of maxillomandibular asymmetries linked to micrognathia. However, it cannot resolve all the factors participating in facial asymmetry, such as those originating in the oculo-auriculo-ventricular spectrum or complex tumor sequelae, and second-step procedures may be required.     

Changes in occlusal force after mandibular ramus osteotomy with and without Le Fort I osteotomy

The purpose of this study was to evaluate the differences in bite force changes and occlusal contacts after sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO) with and without Le Fort I osteotomy. Sixty female patients with diagnosed mandibular prognathism with or without asymmetry were divided into four groups (SSRO, IVRO, SSRO with Le Fort I osteotomy and IVRO with Le Fort I osteotomy). Bite force and occlusal contacts were measured preoperatively and at 1, 3, 6 and 12 months after surgery with pressure-sensitive sheets. The differences among surgical procedures were examined statistically. Maximum bite force and occlusal contacts returned to preoperative levels after between 3 and 6 months. Regarding time-dependent changes in bite force and occlusal contact area, there were no significant differences among the groups. In conclusion, this study suggests that the combination of IVRO or SSRO and Le Fort I osteotomy does not affect postoperative time-dependent changes.     

Evaluation of treatment with unilateral mandibular sagittal split ramus osteotomy and maxillary osteotomy in patients with condylar osteochondroma and mandibular asymmetry: A retrospective case series

The aim of the study was to describe an approach where condylar resection with condylar neck preservation was combined with Le Fort I osteotomy and unilateral mandibular sagittal split ramus osteotomy (SSRO).Patients with a unilateral condylar osteochondroma combined with dentofacial deformity and facial asymmetry who underwent surgery between January 2020 and December 2020 were enrolled. The operation included condylar resection, Le Fort I osteotomy and contralateral mandibular sagittal split ramus osteotomy (SSRO). Simplant Pro 11.04 software was used to reconstruct and measure the preoperative and postoperative craniomaxillofacial CT images. The deviation and rotation of the mandible, change in the occlusal plane, position of the “new condyle” and facial symmetry were compared and evaluated during follow-up. Three patients were included in the present study. The patients were followed up for 9.6 months on average (range, 8–12). Immediate postoperative CT images showed that the mandible deviation and rotation and occlusion plane canting decreased significantly postoperatively; facial symmetry was improved but still compromised. During the follow-up, the mandible gradually rotated to the affected side, the position of the “new condyle” moved further inside toward the fossa, and both the mandible rotation and facial symmetry were more significantly improved.Within the limitations of the study it seems that for some patients a combination of condylectomy with condylar neck preservation and unilateral mandibular SSRO can be effective in achieving facial symmetry.     

Passive repositioning of maxillary fractures: An occasional impossibility without osteotomy

PURPOSE: To present cases where passive repositioning of maxillary fractures was not achievable during surgery, and a method to provide passive occlusal positioning in those cases. PATIENTS AND METHODS: Over a 10-year period, the maxillae of 24 patients with fractures of the maxilla could not be passively repositioned during surgery. In these cases, a Le Fort I osteotomy was performed in addition to reduction and fixation of the other midfacial fractures. RESULTS: All patients had passive restoration of their pretrauma occlusion during surgery. All patients except 1 had maintenance of their pretrauma occlusion at the last follow-up visit (6 weeks or more) following surgery. CONCLUSION: When passive positioning of the maxilla is not possible, a concomitant Le Fort I osteotomy can provide passive positioning of the occlusion.     

Facial asymmetry in temporomandibular joint disorders

In order to investigate skeletal deviation in patients with internal derangement of the TMJ, facial asymmetry was examined by the frontal cephalogram and compared with a control group of asymptomatic subjects. It was demonstrated that mandibular lateral displacement in the patients was significantly greater than that in the controls. The degree of displacement was significantly related to the cant of the frontal occlusal plane and the frontal mandibular plane, indicating the reduced vertical dimension of the posterior occlusal level and the ramus height on the mandibular displaced side. It is concluded that facial asymmetry due to mandibular lateral displacement is a relatively common problem in patients with internal derangement of TMJ. The cant of the frontal occlusal plane seems to be an important occlusal characteristic related to temporomandibular joint dysfunction.     

The treatment of hemimandibular hyperplasia preserving enlarged condylar head.

OBJECTIVE: To present a case of hemimandibular hyperplasia (HH) treated with orthognathic surgery that preserves the condyle without disturbing mandibular function. METHODS: A 27-year-old woman with HH was treated with orthognathic surgery preserving the enlarged condylar head. Radiographic examination showed typical enlargement of the right condyle, elongation of the right ascending ramus and mandibular body, and tilted occlusal plane. A mandibular sagittal split osteotomy on the unaffected side and subcondylar ramus osteotomy on the affected side, Le Fort I wedge osteotomy to relevel the tilted occlusal plane, and contouring of the lower mandibular margin were performed. RESULTS: Excellent results in the full-face appearance and occlusion were obtained. There was no change in the size of the reserved condylar head 4 years postoperatively. In a series of examinations of jaw function with electromyography, mandibular kinesiography, and computer-aided diagnostic axiography, more favorable findings were obtained postoperatively. CONCLUSIONS: In a case of HH without abnormally high growth activity, orthognathic surgery preserving hypertrophic condyle produced functional improvement in addition to good occlusal and aesthetic outcomes.     

Orthognathic treatment for a patient with facial asymmetry associated with unilateral scissors-bite and a collapsed mandibular arch

Subapical mandibular surgeries have been used to correct vertical malocclusion and interdental problems associated with mandibular deformity. Subapical surgery to the anterior part of the mandible is applicable in many patients with anterior open bite and deepbite. Surgery of the posterior part of the mandible is needed less frequently than surgery of the anterior part. This case report describes the surgical-orthodontic treatment of a 21-year-old woman who underwent posterior subapical mandibular surgery. Her chief complaint was facial asymmetry, and she had a collapsed mandibular arch with a scissors-bite of the right premolars and molars. After subapical osteotomy, surgically assisted correction of the collapsed right mandibular arch was performed with a lingual arch appliance. Comprehensive orthodontic treatment was initiated in both arches after this correction. Le Fort I osteotomy and sagittal split ramus osteotomy were used to correct the facial asymmetry. Her facial appearance and temporomandibular problems were markedly improved, and she achieved a functional and stable occlusion after these treatments. This case report demonstrates the efficiency of posterior subapical mandibular surgery for a patient with a collapsed mandibular arch and a scissors-bite.     

Correction of skeletal Class III malocclusion with clockwise rotation of the maxillomandibular complex

A 19-year-old woman with skeletal Class III malocclusion, paranasal depression, and a low mandibular plane angle was treated with orthodontics and orthognathic surgery. Dental decompensation and protraction of maxillary right third molar to replace maxillary right second molar were performed before surgery. Clockwise rotation of maxillo-mandibular complex was applied by Le Fort I osteotomy and bilateral sagittal split osteotomies to achieve facial balance. The active treatment period was 12 months. The stable occlusion and skeletal relationship were observed after a 10-month follow-up period.     

Simultaneous maxillomandibular distraction in unilateral mandibular hypoplasia

In craniomaxillofacial surgery we often deal with hypoplastic mandibles and mandibular asymmetries, the correction of which is critical to obtaining acceptable aesthetic results. In all of them we find common skeletal problems once growth has finished, such as an inclined occlusal plane and facial asymmetry with a stable dental occlusion. Simultaneous maxillomandibular distraction, which involves a Le Fort I osteotomy and a mandibular osteotomy with intermaxillary fixation during the period of active distraction, is an excellent technique to solve these problems. Virtual surgical planning, stereolithographic models, and surgical guides are supportive tools for obtaining excellent results. In this paper we present our experience with five cases of hypoplastic mandibles and mandibular asymmetries of different aetiologies. In all patients we achieved a considerable improvement in their physical appearance in the distance between the lateral canthus and oral commissure, the height of the mandibular ramus, the inclination of the occlusal plane, and the medial position of the chin. The benefits of virtual surgical planning in terms of choosing the optimal vector and the amount of distraction make it a promising technological tool to achieve excellent outcomes.     

Five-year follow-up of Le Fort I osteotomies

The outcome of a five-year radiographic follow-up study of 150 patients with maxillo-mandibular malformations who had undergone Le Fort I osteotomy of the maxilla is reported. A superimposition technique made possible an exact evaluation of the adjustments effected. The results confirm the validity of a study conducted in 1977 and the five-year stability of the maxilla. The importance of the relationship between the Frankfort plane, occlusal plane and the osteotomy line is emphasized. In operations in which Le Fort I osteotomy of the maxilla is combined with a sagittal osteotomy of the mandible the maxilla undergoes minute displacements in the weeks following surgery, which can easily be predicted and allowed for at the planning stage. The long-term stability of the maxilla is assured.     

A 2-stage procedure combining maxillary advancement by distraction technique with mandibular setback surgery in patients with cleft lip and palate

A 2-stage procedure combining maxillary advancement by distraction technique with mandibular setback surgery was used to correct jaw deformities in 5 patients with severe maxillary retrusion secondary to cleft lip and palate. First, a Le Fort I maxillary osteotomy was performed. Immediately after maxillary distraction, the distraction device was removed. The advanced maxilla was fixed with miniplates after adjusting the length and direction of advancement, and mandibular setback surgery was performed simultaneously to obtain a normal occlusal relationship. This 2-stage procedure resulted in stable occlusion and a markedly improved facial profile.     

个性化上颌非对称旋转矫治上颌 平面偏斜畸形

目的评估上颌非对称旋转在矫正 平面偏斜不对称畸形患者中的应用。总结治疗面部不对称畸形患者的经验,为临床治疗面部不对称畸形提供参考。 方法选取32例 平面偏斜的面部不对称畸形患者,拍摄术前螺旋CT及术前、术后头颅正位片,术前在计算机辅助下模拟手术,设计个性化手术方案,不对称旋转上颌 平面,并将模拟数据用于手术中。采用配对t检验进行统计学分析比较术前、术后面部外形差异。 结果32例患者面部形态及功能均取得了良好的治疗效果,无术中及术后并发症发生,软硬组织取得良好对称性,面部外形协调美观。术后双侧上颌骨高度差异[（0.6 ± 0.5）mm]小于术前上颌骨高度差异[（4.7 ± 1.5）mm],差异有统计学意义（t= 15.172,P<0.001）。术后<平面偏斜度[（0.5 ± 0.5）°]小于术前<平面偏斜度[（4.4 ± 1.7）°],差异有统计学意义（t= 12.934,P<0.001）。术后非对称率[（0.7 ± 0.6）%]小于术前非对称率[（5.5 ± 1.7）%],差异有统计学意义（t= 15.640,P<0.001）。 结论（1）数字化计算机辅助外科技术能够模拟手术过程,设计手术方案,重建术后软硬组织形态并指导正颌手术的准确截骨;（2）上颌非对称旋转能够矫正上颌 平面偏斜畸形,达到面部软硬组织对称协调,改善面部不对称畸形。     

Combined maxillary and mandibulardistraction osteogenesis

Mandibular elongation by gradual distraction in patients with hemifacial microsomia is a simple and effective procedure to correct facial asymmetry. The changes in mandibular dimension result in changes in dental occlusion. These are minimal in children because of the rapid growth of the maxilla and can be corrected easily with minor orthodontic treatment. Mandibular distraction in adults with hemifacial microsomia produces good aesthetic results but leaves the patient with a severe alteration in the occlusion requiring complex orthodontic treatment over a long period of time. To avoid this problem, an incomplete Le Fort I osteotomy is performed simultaneously with the mandibular corticotomy. Intermaxillary fixation is placed on the fifth postoperative day, and distraction is initiated. This technique preserves the preexisting stable occlusion. After distraction, both the maxillary and mandibular occlusal planes become horizontal, and facial asymmetry is corrected.     

Cranial nerve injury after Le Fort I osteotomy

A Le Fort I osteotomy is widely used to correct dentofacial deformity because it is a safe and reliable surgical method. Although rare, various complications have been reported in relation to pterygomaxillary separation. Cranial nerve damage is one of the serious complications that can occur after Le Fort I osteotomy. In this report, a 19-year-old man with unilateral cleft lip and palate underwent surgery to correct maxillary hypoplasia, asymmetry and mandibular prognathism. After the Le Fort I maxillary osteotomy, the patient showed multiple cranial nerve damage; an impairment of outward movement of the eye (abducens nerve), decreased vision (optic nerve), and paraesthesia of the frontal and upper cheek area (ophthalmic and maxillary nerve). The damage to the cranial nerve was related to an unexpected sphenoid bone fracture and subsequent trauma in the cavernous sinus during the pterygomaxillary osteotomy.     

Maxillary distraction resulting in facial advancement at Le Fort III level in cleft lip and palate patients: a report of two cases

An 18-year-old female and a 14-year-old male who had previously received surgery for primary repair of a nonsyndromic cleft lip and palate (including alveolar defect bone grafting) unintentionally developed facial advancement at the Le Fort III level after surgical correction of their maxillary hypoplasia. The Le Fort I osteotomy, originally performed for their maxillary dentoalveolar hypoplasia, was an incomplete osteotomy. It was performed without down-fracture, leaving the pterygomaxillary and septal junctions intact. The gradual advancement of the maxilla during distraction osteogenesis was planned to correct the hypoplastic maxilla, and also prevent subsequent hypernasality; however, during the distraction procedure by means of a rigid external device both patients developed an unintentional facial advancement at the Le Fort III level.     

Surgical orthodontic treatment for a patient with unilateral cleft lip and palate and temporomandibular disorder

The patient was a 12-year-old female who presented with unilateral cleft lip and palate, facial asymmetry, mandibular protrusion, resorption of condyle heads, and transverse maxillary deficiency. At the age of 13 years 10 months, maxillary expansion and autogenous bone graft were performed to improve the maxillary collapsed arch. Aged 14 years 10 months, she described symptoms of temporomandibular joint pain and dysfunction. Segmental Le Fort I osteotomy and intraoral vertical ramus osteotomy (IVRO) were performed at the age of 15 years 11 months. Segmental Le Fort I osteotomy resulted in improved sagittal and transverse discrepancy of the maxilla. After IVRO, facial symmetry, a good facial profile, and disappearance of TMD symptoms were achieved. The occlusion and esthetics were stable after 5 years of retention.     

Osteogenic distraction and orthognathic surgery to correct sequelae of ankylosis of the temporomandibular joint: a case report

A 17-year-old female patient presented with sequelae to ankylosis of the temporomandibular joint, which included vertical maxillary protrusion, anterior open bite, labial incompetence, micrognathia, undefined neck angle, facial asymmetry, Class II molar relationship, and Class III canine relationship. She presented with the following cephalometric and soft tissue data: SNA angle = 78 degrees, SNB angle = 70 degrees, incisor-nasion-point A = 11 degrees, incisor-nasion-point B = 33 degrees, Frankfort-mandibular plane angle = 43 degrees, occlusal plane = 25 degrees, subnasale-stomion = 20 mm, stomion superius-stomion inferius = 9 mm, stomion inferius-soft tissue menton = 30 mm, neck angle = 144 degrees, and chin projection = 10 mm. Orthognathic surgery and mandibular osteogenic distraction were employed, specifically Le Fort I osteotomy to decrease a vertical excess of 12 mm, augmentation genioplasty of 17 mm, and bilateral extraoral distractors of bidirectional vector for a 14-mm augmentation of the mandible. The result was satisfactory with minimal adverse complications.