上颌中线定位在矫治下颌骨偏突颌畸形中的意义

目的:分析下颌骨偏突颌畸形(Ⅲ类)合并上颌中线偏斜的颅面形态特征,总结分析采用正畸-正颌联合治疗矫治此类畸形的特点及难点。方法:通过对20例下颌偏突颌畸形(Ⅲ类)正畸-正颌联合治疗前后资料的对比分析,探讨该类牙颌面畸形的临床特点,以及正颌手术前后合理的正畸治疗,特别是上颌中线定位对保证功能与形态效果的重要性。结果:术前正畸疗程为10～20个月,平均18个月。术后正畸疗程为5～10个月,平均8个月。术前正畸必须解决:①去除患者三维方向的牙代偿;②协调其牙弓形态及宽度的不调;③矫正上颌中线。术后正畸治疗的主要目的是对咬合关系进行精细调整。19例患者均获得满意效果,1例患者上颌中线未完全改正。结论:下颌骨偏突颌畸形(Ⅲ类)合并上颌中线偏斜的临床表现复杂,有别于单纯的骨性Ⅲ类畸形,正颌手术前后的正畸治疗是保证矫治效果达到功能形态俱佳的关键,其中术前上颌中线的准确定位尤其关键。     

骨性Ⅲ类错畸形术前术后正畸治疗的临床研究

目的探讨经正畸正颌联合治疗的骨性Ⅲ类错畸形患者的术前术后正畸治疗特点。方法 25例经完善的正畸正颌联合治疗的骨性Ⅲ类错畸形患者,分析治疗前(T0)、术前正畸治疗后(T1)、及矫治结束后(T2)的头颅定位侧位X线片,分析其不同时期的硬组织变化,总结术前术后正畸治疗特点。结果所有患者面部外形都较治疗前明显改观,咬合及功能改善。尽管头影测量结果显示骨面型:面角、颌凸角等变化明显,但术前正畸去代偿并不完全,上颌牙齿的代偿依然存在。术后的正畸主要是稳定手术后的颌骨关系和精细调整咬合,类似于综合性的正畸治疗。结论正畸正颌联合是治疗骨性Ⅲ类错畸形的有效手段,而治疗效果的日臻完善需要正畸正颌治疗的密切配合。     

正颌外科矫治骨性Ⅲ类错牙合中的正畸治疗

颌骨发育异常导致严重颌面部畸形，须采用正畸及外科相结合的方法才能使牙、颌、面获得平衡、协调的关系，恢复面部美观及咬合功能。下颌骨前突而形成骨性Ⅲ类错牙合是临床上最常应用正颌外科矫治的类型［１］。为了取得最佳的疗效，保持稳定的治疗效果，外科手术前后均应...     

上颌拔牙矫治对骨性Ⅲ类错牙合畸形正颌术前牙弓宽度影响研究

目的 评价骨性Ⅲ类错牙合畸形患者正颌术前正畸治疗中拔除与不拔除上颌第一前磨牙对牙弓横向宽度的影响,为是否在术前正畸中拔除上颌前磨牙提供一个参考指标。方法 选择2007年1月至2012年7月在大连市口腔医院接受正畸-正颌联合治疗的骨性Ⅲ类错牙合畸形患者28例,其中12例术前正畸采取拔牙矫治（拔牙组）,16例采取不拔牙矫治（非拔牙组）。对两组病例正畸治疗前后的模型进行牙弓宽度对比研究。结果 经过术前正畸治疗,拔牙组较非拔牙组的上颌后段牙弓宽度减小明显,差异有统计学意义（P < 0.05）;拔牙组与非拔牙组的下颌牙弓中段及后段宽度均有增加,但两组差异无统计学意义（P > 0.05）。结论 在骨性Ⅲ类错牙合畸形的正畸-正颌外科联合治疗中,拔除上颌第一前磨牙有利于术前正畸有效去除后牙代偿,协调上下牙弓间横向关系,为正颌手术创建良好条件。     

成人严重骨性Ⅲ类错畸形手术前后的正畸治疗

目的:研究成人严重骨性Ⅲ类错畸形在正颌外科治疗的术前与术后正畸的特点及难点。方法:成人严重骨性Ⅲ类错病例35例,对该类畸形的临床特点、正颌手术前后正畸治疗方法和注意事项进行分析研究。结果:术前正畸治疗必须完成个别牙齿错位的调整,纠正牙弓形态与宽度的不调和牙齿代偿的去除;术后正畸的主要目的是牙弓内残留间隙的关闭和咬合关系的进一步精细调整。结论:只有完善的术前、术后正畸治疗与正颌外科手术相互配合,才能较好地完成成人严重骨性Ⅲ类错的临床治疗。     

成人严重骨性Ⅲ类错牙合术前正畸及手术设计

提要：骨性Ⅲ类错牙合的正畸-正颌联合治疗是临床中比较复杂的情况之一。正畸-正颌联合治疗一般包括术前正畸、正颌手术及术后正畸3个阶段：排齐上下牙列,去除牙代偿,协调上下颌牙弓;采用颏成形术、单颌或双颌手术后退下颌骨或（和）前移上颌骨,改善侧貌美观;术后精细调整,形成良好咬合关系。治疗应根据患者颌骨畸形的严重程度、上下唇形态、颏部位置、牙列拥挤度、牙齿倾斜度等畸形特征,具体分析,严格把握适应证,对于边缘病例尤应重视。矫治过程中,应重视术前正畸和手术设计,为正颌手术提供便利。     

Ⅲ类错(牙合)下颌偏斜正畸疗效的初步分析

目的 探讨Ⅲ类错(牙合)牙性、功能性和轻度骨性下颌偏斜的正畸矫治效果,为临床治疗提供参考.方法 选择Ⅲ类错(牙合)牙性、功能性和轻度骨性下颌偏斜患者共35例,男性14例,女性21例,年龄7～22岁(平均16.5岁).牙性偏斜主要通过扩大上颌牙弓,促使下颌自动复位;功能性下颌偏斜应用双颌式功能矫正器或不对称性前方牵引和Ⅲ类颌间牵引进行治疗;轻度骨性下颌偏斜行拔牙正畸掩饰性治疗.结果 通过正畸临床矫治,22例Ⅲ类错(牙合)牙性和功能性下颌偏斜患者的颜面外形和咬合均达到满意的疗效.13例Ⅲ类错(牙合)骨性下颌偏斜患者,拔牙掩饰性正畸矫治仅可改善颜面美观.结论 Ⅲ类错(牙合)牙性和功能性下颌偏斜是正畸治疗的适应证;而对于Ⅲ类错(牙合)轻度骨性下颌偏斜的患者,单纯正畸治疗仅可减轻牙(牙合)畸形的程度.     

正畸-正颌手术联合治疗严重骨性Ⅲ类错（牙合）畸形

正颌外科在我国兴起于上世纪70年代末和80年代初[1],这对于颅面部严重骨性畸形的治疗具有划时代的意义.严重骨性Ⅲ类错（牙合）畸形就是一类常见牙颌面畸形,不仅影响患者的容貌、发音和咀嚼功能,甚至影响心理健康,有研究[2]表明此类人群常有敏感多疑、自卑、对人不信任等表现,所以进行治疗是非常必要的,但是由于骨性畸形严重,单纯正畸治疗难以取得良好的治疗效果,虽然也有采用非手术治疗严重骨性Ⅲ类错（牙合）的报告[3],但矫治难度大,对正畸医师技术要求高,难以推广,所以对于严重骨性Ⅲ类错（牙合）成年患者而言,采用正畸-正颌外科联合矫治是目前临床最常用的治疗手段.     

成人严重骨性Ⅲ类错(牙合)畸形手术前后的正畸治疗

目的：研究成人严重骨性Ⅲ类错耠畸形在正颌外科治疗的术前与术后正畸的特点及难点。方法：成人严重骨性Ⅲ类错胎病例35例，对该类畸形的临床特点、正颌手术前后正畸治疗方法和注意事项进行分析研究。结果：术前正畸治疗必须完成个别牙齿错位的调整，纠正牙弓形态与宽度的不调和牙齿代偿的去除：术后正畸的主要目的是牙弓内残留间隙的关闭和咬合关系的进一步精细调整。结论：只有完善的术前、术后正畸治疗与正颌外科手术相互配合，才能较好地完成成人严重骨性Ⅲ类错胎的临床治疗。     

24例骨性Ⅲ类伴偏颌畸形患者隐形正畸-正颌联合治疗效果分析

目的:评价骨性Ⅲ类伴偏颌畸形患者采用无托槽隐形矫治技术进行正畸-正颌联合治疗的临床效果.方法:回顾正畸-正颌联合治疗的骨性Ⅲ类伴偏颌畸形患者24例,其中,实验组(n=12)采用无托槽隐形矫治技术,对照组(n=12)采用传统固定矫治技术,分别进行术前和术后正畸治疗.比较、分析2组患者治疗前、后的头影测量指标及满意度问卷调...     

Early orthognathic surgery with three-dimensional image simulation during presurgical orthodontics in adults

To correct dentofacial deformities, three-dimensional skeletal analysis and computerized orthognathic surgery simulation are used to facilitate accurate diagnoses and surgical plans. Computed tomography imaging of dental occlusion can inform three-dimensional facial analyses and orthognathic surgical simulations. Furthermore, three-dimensional laser scans of a cast model of the predetermined postoperative dental occlusion can be used to increase the accuracy of the preoperative surgical simulation. In this study, we prepared cast models of planned postoperative dental occlusions from 12 patients diagnosed with skeletal class III malocclusions with mandibular prognathism and facial asymmetry that had planned to undergo bimaxillary orthognathic surgery during preoperative orthodontic treatment. The data from three-dimensional laser scans of the cast models were used in three-dimensional surgical simulations. Early orthognathic surgeries were performed based on three-dimensional image simulations using the cast images in several presurgical orthodontic states in which teeth alignment, leveling, and space closure were incomplete. After postoperative orthodontic treatments, intraoral examinations revealed that no patient had a posterior open bite or space. The two-dimensional and three-dimensional skeletal analyses showed that no mandibular deviations occurred between the immediate and final postoperative states of orthodontic treatment. These results showed that early orthognathic surgery with three-dimensional computerized simulations based on cast models of predetermined postoperative dental occlusions could provide early correction of facial deformities and improved efficacy of preoperative orthodontic treatment. This approach can reduce the decompensation treatment period of the presurgical orthodontics and contribute to efficient postoperative orthodontic treatments.     

Open-bite closure by intruding maxillary molars with skeletal anchorage

Most anterior open bite cases are characterized by the excessive vertical development of the posterior maxilla. Intrusion of the overerupted molar teeth with traditional orthodontic methods is hardly possible; therefore, there is no real alternative to a combined orthodontic and surgical approach. Skeletal anchorage has recently been offered for the orthodontic movement of teeth. Titanium miniplates implanted in the zygomatic buttress area can serve as absolute anchorage for maxillary molar intrusion. The aim of this study was to evaluate skeletal anchorage for closing open-bite malocclusions. Seven patients with severe anterior open-bites were selected. In all cases the deformity was due to the overeruption of the maxillary molars. Titanium miniplates were inserted bilaterally in the zygomatic buttress region. Fixation was performed with 3 miniscrews. Elastic bands or coil springs were used to reduce excessive maxillary molar heights. The mean active treatment time was 6 months. In all cases the anterior open-bite significantly improved. No side-effects were observed. Our results suggest that skeletal anchor plates offer successful treatment for closing skeletal anterior open bites.     

Treatment planning in Class III malocclusion

In Class III malocclusion, the overjet is reduced and may be reversed, with one or more incisor teeth in lingual crossbite. In the early mixed dentition, and in older patients with mild skeletal discrepancies, orthodontic treatment usually involves proclining the maxilliary anterior teeth into positive overjet. When the permanent dentition has established, orthodontic therapy is usually aimed at compensating for the underlying mild-moderate Class III skeletal discrepancy by proclining and retroclining the maxillary and mandibular incisors, respectively. In contrast, adolescent and non-growing patients with severe Class III skeletal discrepancies require a combination of orthodontic treatment and orthognathic surgery to correct the underlying skeletal pattern. Adolescent patients with moderately severe skeletal discrepancies require careful treatment planning because they are often at the limits of orthodontic compensation, and further mandibular growth may prevent a stable Class I occlusion from being maintained with growth. In this situation, treatment should be limited to aligning the maxillary arch, accepting that orthognathic surgery will be required to correct the underlying Class III skeletal discrepancy when skeletal growth has been completed. This article will inform dental professionals about the aetiology, assessment, diagnosis and treatment of patients with Class III malocclusions. Specifically, the types of orthodontic treatment that can be completed at the various stages of dental development and skeletal growth will be discussed.     

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.     

下颌前突外科手术前后的正畸治疗

目的 总结、分析口腔正畸－正颌外科联合矫治下颌前突畸形的治疗经验,以指导临床工作。方法 对４０例年龄为１７￣３８岁的下颌前突患者经口腔正畸与正颌外科联合矫治的资料进行分析。结果 ４０例下颌前突患者平均术前正畸治疗时间９个月（２￣２５个月）,术后正畸治疗时间７．６个月（２￣１５个月）。整个治疗过程平均１６个月（４￣２５个月）。术前正畸治疗的目标为排齐上下牙列,完成切牙和磨牙的去代偿治疗,整平牙例,协     

Extreme skeletal open bite correction with vertical elastics

Severe skeletal open bites may be ideally treated with a combined surgical–orthodontic approach. Alternatively, compensations may be planned to camouflage the malocclusion with orthodontics alone. This case report describes the treatment of an 18-year-old man who presented with a severe open bite involving the anterior and posterior teeth up to the first molars, increased vertical dimension, bilateral Class III molar relationship, bilateral posterior crossbite, dental midline deviation, and absence of the maxillary right canine and the mandibular left first premolar. A treatment plan including the extraction of the mandibular right first premolar and based on uprighting and vertical control of the posterior teeth, combined with extrusion of the anterior teeth using multiloop edgewise archwire mechanics and elastics was chosen. After 6 months of alignment and 2 months of multiloop edgewise archwire mechanics, the open bite was significantly reduced. After 24 months of treatment, anterior teeth extrusion, posterior teeth intrusion, and counterclockwise mandibular rotation were accomplished. Satisfactory improvement of the overbite, overjet, sagittal malocclusion, and facial appearance were achieved. The mechanics used in this clinical case demonstrated good and stable results for open-bite correction at the 2-year posttreatment follow-up.     

Dentoskeletal treatment changes in Class II subdivision malocclusions in submentovertex and posteroanterior radiographs.

The objective of this study was to evaluate the dentoskeletal changes consequent to orthodontic treatment in subjects with Class II subdivision malocclusions, treated with asymmetric extractions, compared with a normal-occlusion control group. The sample consisted of 3 groups, with 30 subjects in each: normal-occlusion subjects (group 1), untreated Class II subdivision subjects (group 2), and Class II subdivision patients treated with asymmetric extractions (group 3). All subjects had a full complement of permanent teeth at the beginning of treatment. The average ages of the subjects were 22.42, 15.76, and 18.57 years, respectively, in groups 1, 2, and 3. Measurements of relative differences in the spatial position of dental and skeletal bilateral landmarks were obtained from the submentovertex and posteroanterior cephalometric (PA) radiographs. The t test for independent samples was used to compare group 1 with groups 2 and 3 at different times. Results from the submentovertex radiograph showed that asymmetric extractions in Class II subdivision malocclusions will maintain the differences in the anteroposterior positions of right and left, maxillary and mandibular first molars, as would be expected with the treatment protocols used. There were no significant skeletal changes that could be attributed to the treatment approaches investigated or transverse collateral effects with the asymmetric mechanics used. It was also demonstrated that treatment of Class II subdivision malocclusions with asymmetric extractions produced corrections of maxillary and mandibular dental midline deviations with the midsagittal plane, without canting the occlusal plane or any other investigated horizontal plane, as seen in the PA radiograph. Treatment of Class II subdivision malocclusions with asymmetric extractions constitutes a beneficial approach to this problem.     

The use of skeletal anchorage in open bite treatment: a cephalometric evaluation

The aims of the present study were to assess the effectiveness of skeletal anchorage for intrusion of maxillary posterior teeth, to correct open bite malocclusion, and to evaluate the usage of titanium miniplates for orthodontic anchorage. Anterior open bite is one of the most difficult malocclusions to treat orthodontically. Currently, surgical impaction of the maxillary posterior segment is considered to be the most effective treatment option in adult patients. Various studies have reported the use of implants as anchorage units at different sites of midfacial bones for orthodontic tooth movement. The zygomatic buttress area could be a valuable anchorage site to achieve intrusion of maxillary posterior teeth. Ten patients, 17 to 23 years old and characterized with an anterior open bite and excessive maxillary posterior growth, were included in this preliminary study. Titanium miniplates were fixed bilaterally to the zygomatic buttress area, and a force was applied bilaterally with nine mm Ni-Ti coil springs between the vertical extension of the miniplate and the first molar buccal tube. The results showed that, with the help of skeletal anchorage, maxillary posterior teeth were intruded effectively. As compared with an osteotomy, this minimally invasive surgical procedure eased treatment and reduced treatment time and did not require headgear wear or anterior box elastics for anterior open bite correction. In conclusion, the zygomatic area was found to be a useful anchorage site for intrusion of the molars in a short period of time.     

Mandibular widening by intraoral distraction osteogenesis

Transverse mandibular deficiency with crowding of the mandibular anterior teeth is frequently present in patients with Class I and II malocclusions. The hallmarks of treatment by compensating orthodontics, functional appliances or orthopaedic devices are instability, compromised periodontium and compromised facial aesthetics. A new surgical technique has been developed to widen the mandible. The method is based upon gradual osteodistraction following vertical interdental symphyseal osteotomy. Ten patients with transverse mandibular deficiency and significant dental crowding were treated by symphyseal distraction and subsequent non-extraction decompensating orthodontic treatment. Either an intraoral tooth-borne Hyrax appliance or a new custom-made bone-borne osteodistractor was used to gradually widen the mandible. The surgical procedures were accomplished under local anaesthesia and intravenous sedation in an ambulatory surgical setting using an individualized distraction protocol. The appliances were activated 7 days after symphyseal osteotomies, once each day at a rate of 1 mm per day and stabilized for 30–60 days after distraction. After the segments were distracted, non-extraction orthodontic alignment of the mandibular anterior teeth was accomplished. The symphyseal distraction gaps were bridged by new bony regenerate. Distraction osteogenesis provided an efficient surgical alternative to orthognathic surgery for widening the mandible and treatment of transverse mandibular deficiency without extraction of teeth.     

骨性Ⅲ类错下前牙区牙槽骨形态的锥形束CT分析

目的:应用锥形束CT(cone-beam computed tomography,CBCT)评价骨性Ⅲ类和骨性Ⅰ类错患者下颌切牙区牙槽骨形态的差异。方法:选取45例恒牙期骨性Ⅲ类错病例及45例恒牙期骨性Ⅰ类错病例矫治前的CBCT图像,测量下切牙区的牙槽骨厚度,应用SPSS16.0软件包对测量结果进行团体t检验。结果:骨性Ⅲ类组唇侧、舌侧、唇舌侧总牙槽骨厚度平均值分别为2.0437mm、3.0750mm和5.1187mm,骨性Ⅰ类组唇侧、舌侧、唇舌侧总牙槽骨厚度平均值分别为2.6176mm、4.2765mm和7.0941mm。2组间唇侧、舌侧和唇舌侧总牙槽骨平均厚度均有显著差异(P<0.01)。结论:骨性Ⅲ类错患者的下前牙区牙槽骨存在菲薄的现象,提示在正畸治疗过程中,无论是内收下前牙还是去代偿正畸,均要警惕牙槽骨吸收和牙根暴露。