前牙开正畸治疗和外科治疗的限度

目的　探讨前牙开畸形正畸治疗与外科治疗的界限。方法　选择正畸治疗开患者70人 ,平均年龄 18 0岁 ;外科治疗开患者 14人 ,平均年龄 2 5 1岁。对经计算机头影测量得出的15 4项颅面软硬组织测量项目值进行单因素和多因素判别分析。结果　下切牙下颌平面角 (L1MP)可作为单因素判别指标 ,当其值≤ 89 5°时 ,可判断为外科治疗的适应证 ,>89 5°时则判断为正畸治疗。根据多因素逐步判别分析建立的判别函数 :Z =- 0 80 188L1MP +0 9140 1Age +0 6 71111Antigonialnotch MP +0 5 99992SNPg ,当Z≥ 0时 ,判定为外科治疗组 ,Z <0时判为正畸治疗组。结论单因素判别指标和多因素判别函数均可用于确定正畸治疗与外科治疗的界限 ,判别函数优于单因素判别指标。     

骨性Ⅲ类错（牙合）正畸-外科联合治疗后牙齿长期稳定性研究

目的　探讨口腔正畸 正颌外科联合治疗前后不同阶段牙齿的变化和术后的稳定性。方法　选取 31例在北京大学口腔医学院进行口腔正畸 正颌外科联合治疗的骨性安氏III类错患者 ,对其不同阶段X线头影测量片进行研究。结果　牙齿在术前正畸阶段有明显的去代偿 ,下切牙平均唇倾 7 0 8°。在术中 ,上切牙随颌骨的旋转有直立 ,下切牙有后移。术后 ,上切牙有唇向复发 ,下切牙相对于基骨稳定。术后牙齿保持良好的咬合 ,而且主要变化发生在术后正畸阶段。结论　III类错患者在术前正畸阶段牙齿明显去代偿 ,术后上前牙稍有复发 ,下前牙相对保持稳定     

安氏Ⅲ类成人患者手术非手术治疗的判别分析

目的用判别分析对安氏Ⅲ类成人患者的手术非手术治疗进行判别及预测.方法从北京大学口腔医学院正畸科1997-1999年就诊的患者中收集86名安氏Ⅲ类成人患者,其中53人接受了正畸和正颌联合治疗,33人接受了单纯正畸治疗.两组之间的性别及年龄差异均无显著性.为了评价所形成判别方程的准确性,9名患者被随机选出形成"校验样本",剩余77名患者作为"训练样本"进行了判别分析.结果判别分析选出了5项敏感的测量项目MP/FH,BsLL/FH,G-Pos(FH),ANS-Me和A-Pg(OP).标准判别方程为Y=0.384 MP/FH+0.916 BsLL/FH-0.595 G-Pos(FH)-0.512ANS-Me+0.857A-Pg(OP).分类方程为Y1=-65.797+0.829 MP/FH+1.34 BsLL/FH-0.411 G-Pos(FH)+0.185ANS-Me+0.315A-Pg(OP);Y2=-49.483+0.682 MP/FH+1.043 BsLL/FH-0.277 G-Pos(FH)+0.309 ANS-Me-0.048 A-Pg(OP).训练样本的判别准确性为89.6%,校验样本的判别准确性为88.9%.结论软硬组织颏部位置、下唇形态和面部骨骼前下部位垂直向高度在判别安氏Ⅲ类患者手术非手术治疗有明显的影响作用,患者的观点和功能性因素也应加以考虑.     

正颌外科矫治骨性下颌偏斜的术前及术后正畸治疗

目的　分析、总结临床采用正畸 正颌外科方法联合治疗严重骨性下颌偏斜畸形时术前与术后正畸治疗中的难点和要点 ,为临床工作提供参考。方法　严重骨性下颌偏斜畸形患者 2 1例 ,年龄 19～ 2 8岁 ,平均年龄 2 5 5岁。ANB角 - 3°～ - 8° ,Wits值 - 7～ - 14mm ,颏点偏斜 3～ 7mm。所有患者均接受术前及术后正畸治疗。结果　术前正畸疗程为 10～ 2 0个月 ,平均 18个月。术后正畸疗程为 5～ 10个月 ,平均 7 5个月。术前正畸治疗必须要解决以下主要难点 :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双颌手术时模型外科分析与导板的制作。术后正畸治疗的主要目的是对咬合关系进行精细调整。结论　术前术后正畸治疗是正颌外科治疗下颌偏斜畸形取得良好效果的必要保证     

骨性Ⅲ类错He正畸—外科联合治疗后牙齿长期稳定性研究

目的探讨口腔正畸-正颌外科联合治疗前后不同阶段牙齿的变化和术后的稳定性.方法选取31例在北京大学口腔医学院进行口腔正畸-正颌外科联合治疗的骨性安氏Ⅲ类错(牙合)患者,对其不同阶段X线头影测量片进行研究.结果牙齿在术前正畸阶段有明显的去代偿,下切牙平均唇倾7.08°.在术中,上切牙随颌骨的旋转有直立,下切牙有后移.术后,上切牙有唇向复发,下切牙相对于基骨稳定.术后牙齿保持良好的咬合,而且主要变化发生在术后正畸阶段.结论Ⅲ类错(牙合)患者在术前正畸阶段牙齿明显去代偿,术后上前牙稍有复发,下前牙相对保持稳定.     

儿童下颌后缩畸形的双期矫正治疗

目的　介绍一种儿童下颌后缩畸形的矫治方法。方法　Ⅰ期治疗用Activator +口外弓矫治 ,改善上下颌骨矢状不调。Ⅱ期用直丝弓矫治器进一步稳定上下颌骨关系 ,精确调整牙位与牙合位。结果　经X线头影测量 :SNB增加 2 .4° ,Go Pg增加 2 .5mm ,Z Angle增加 3.99° ,ANB减少 2 .8° ,|—SN减少 6 .10° ,|—MP减少 3.2 6°。结论　双期矫治儿童下颌后缩畸形是较好的方法之一。     

正畸治疗中牙根吸收的远期观察研究

大量研究表明在正畸治疗中存在着牙根吸收。通常牙根吸收较轻微,但也有少量患者会发生严重根吸收。一般认为:正畸治疗前先存的根吸收是引起正畸治疗中根吸收的诱因,并与个体差异,矫治器类型及矫治力大小有关。本研究目的即为了观察当矫治结束,矫治器去除后,根吸收是继续进展还是停止了。材料和方法100例患者,男性27例,女性73例。平均年龄13.6岁,平均疗程2.2年。正畸治疗前、后及治疗结束后三个月各拍一套全日牙片。并将牙根吸收分成4个等级,读片并分析。I°:牙根长度与治疗前一致,但根尖不规则;Ⅱ°:根吸收少于2mm,Ⅲ°:根吸收多于2mm,不超过根长的1/3;Ⅳ°:根吸收超过根长1/3.结果52%为Ⅰ°根吸收;40%为Ⅱ°根吸收;7%Ⅲ°根吸收;Ⅳ°根吸收仅为1%。另外,X 线片上可     

"摇椅形"弓丝治疗开(牙合)产生的作用力的研究

目的　通过分别测量“摇椅形”弓丝对标准模型前牙及磨牙产生作用力的大小 ,与多曲方丝弓作用力对比寻找适合治疗开畸形应用的最佳性质及弧度的弓丝。方法 :利用组合测量装置分别测出各种弓丝对模型前牙及磨牙的作用力。结果 :15°、2 0°、2 5°的 0 .0 16× 0 .0 2 2″、0 .0 17× 0 .0 2 5″NiNi方丝0 .0 14″不锈钢弓丝及 15°2 0°的 0 .0 16″的不锈钢弓丝弯制成的“摇椅形”弓丝对前牙及磨牙产生的力与0 .0 16× 0 .0 2 2″多曲方丝对牙齿产生的力相近。结论 :建议临床应用“摇椅形”弓丝治疗开患者尽可能应用筛选出的弓丝     

直丝弓滑动技术拔牙矫治骨性Ⅱ类错He的Steiner分析

目的探讨直丝弓滑动技术拔牙矫治骨性Ⅱ类错的治疗变化和代偿机制.方法选择16例骨性Ⅱ类错患者,平均年龄12.1岁.拔除4个第一前磨牙,应用直丝弓滑动技术治疗.进行治疗前后X线头影测量Steiner分析,并做配对t检验和逐步回归分析.结果SNA角减少1.1°,SNB角增加1.3°,上切牙回收4.1mm,下切牙回收1.3mm.治疗后U1NA角为21.3°,L1NB角为33.0°.得到回归方程ANB=0.19×L1NB-0.10×U1NA+0.27.结论直丝弓滑动技术拔牙矫治骨性Ⅱ类错,可使上切牙大量的内收,下切牙少量后移,同时上下颌骨发生了生长或改建.矫治骨性Ⅱ类错的代偿机制主要依靠下切牙一定程度内的唇倾,而上切牙牙轴的代偿作用不太明显,其倾斜角度基本上在正常值范围内.     

替牙期假性安氏Ⅲ类错He的牙颌特征

目的研究替牙期假性安氏III类错(牙合)的牙颌特征,为早期诊断提供依据.方法假性安氏III类错(牙合)组包括替牙期拍摄的36张头颅侧位片.该组为追踪观察至生长发育期后确定为假性安氏III类错(牙合)的患者(女15名,男21名),替牙期拍摄头颅侧位片时的平均年龄为10.7±2.0岁.选择标准为①安氏Ⅰ类磨牙关系,前牙反(牙合);②功能性下颌前移位.真性安氏III类错组包括替牙期拍摄的40张头颅侧位片.该组为追踪观察至生长发育期后确定为真性安氏III类错并接受正颌手术治疗的患者(女21名,男19名),替牙期拍摄头颅侧位片时的平均年龄为9.7±2.2岁.选择标准为安氏III类磨牙关系,前牙反(牙合).安氏Ⅰ类错(牙合)组包括31名安氏Ⅰ类错(牙合)患者(女17名,男14名),平均年龄为11.2±1.4岁.选择标准为①安氏Ⅰ类骨面型,②覆(牙合)覆盖正常,③轻度或中度牙列拥挤,④正中(牙合)位时为直面型.结果假性安氏III类错组中,女性"A"点到N perp的距离平均值为-1.63mm,与安氏Ⅰ类错(牙合)女性平均值0.52 mm相比,差异有显著性(P＜0.05).假性安氏III类错(牙合)组上切牙较直立.结论替牙期假性安氏III类错(牙合)组的牙颌特征为①面中部长度(Co-A)稍短,②下颌功能性前移位,但下颌长度正常,③上前牙舌倾,下前牙倾斜度正常,④垂直向生长发育正常.     

骨性开畸形正颌外科手术前后的正畸治疗

目的：通过分析总结骨正开He畸形手术前后正畸治疗的原则和方法,以指导临床。方法：前牙开He畸形32例,男性9例,女性23例,开He度1－8．5mm,平均4mm31例伴下颌前突,1例伴下颌后。单纯术前正8 ,纯术后正3 ,余21例在手术前后均行正畸治疗。结果：术产术畸疗程为4－33个月,平均12个月;术后正畸疗程为3－17个月,平均8．5个月。开He畸形的术前治疗的;排齐上下牙列,解除牙列拥挤;去代偿治疗,避免上下切牙He向伸长移;支上下牙列列的唇颊向倾斜度。上下颌骨垂直牵引,防止开He复发,上下颌间Ⅱ类或Ⅲ类牵引,调整磨牙关系,结论通过系统的术前术后正畸治疗及正颌外科手术,可矫正前牙开He畸形,并取得良好的矫治效果。     

应用"摇椅形"弓丝矫治前牙开牙合的临床研究

目的　研究“摇椅形”弓丝对前牙开牙合畸形的矫治效果。方法　对 14例前牙开牙合的患者应用“摇椅形”弓丝同时配合前牙区垂直牵引进行矫治 ,通过分析矫治前后X线头颅定位侧位片 ,评价其矫治效果。结果　矫治后上下颌切牙伸长、内收 ,下颌磨牙直立 ,牙合平面改建 ;同时控制了开牙合患者垂直方向的生长。结论　应用“摇椅形”弓丝同时配合前牙区垂直牵引矫治开牙合畸形符合利用固定矫治器治疗开牙合的机理 ,能获得良好的矫治效果。     

Osteotomy assisted maxillary posterior impaction with miniplate anchorage

This case report presents orthodontic treatment with miniplate anchorage accelerated by osteotomy-assisted maxillary posterior impaction in a severe open bite case. A 14-year-old girl with a severe anterior open bite was treated by intrusion of the maxillary posterior teeth. A segmental osteotomy was applied, and the miniplates were fixed to the zygomatic buttress area. The intrusive force was applied with nickel-titanium closed coil springs using a force of 250 g between the miniplates and the upper first and second molar buccal tubes. The intrusion was completed 2.5 months after osteotomy. The treatment was continued with the fixed orthodontic appliances and completed after 12 months. At the end of treatment, optimal occlusion and the correction of the anterior open bite were achieved. The maxillary molars were impacted 4.0 mm, and the mandibular plane showed a counterclockwise autorotation of 3.0 degrees . The results showed that osteotomy-facilitated orthodontic treatment clearly reduced the treatment time and had no adverse effects. In conclusion, this one-stage osteotomy technique can be an effective option to help molar intrusion in severe open bite cases.     

Nonsurgical treatment of open bite in nongrowing patients

Successful treatment of the adult patient with an open bite dental or skeletal pattern often presents a difficult challenge. While the causes of open bite may be multifactorial in nature, there are specific diagnostic criteria that may allow for an orthodontic treatment modality incorporating extraction therapy with retraction of incisors. Two case presentations illustrate treatment of adult patients with open bites due to proclined incisors. The diagnostic criteria and mechanics for appropriate and successful treatment are discussed. Although the selection of extraction therapy for correction of anterior open bite has a narrow range of application in the overall scheme of open bite treatment, this treatment method has certain areas of application in which success may be anticipated. (AM J ORTHOD DENTOFAC ORTHOP 1995;108:651-9.)     

正畸-正颌手术联合矫治骨性开(牙合)的长期稳定性研究

目的 研究正畸-正颌手术联合矫治骨性开15年后的骨性以及牙性变化.方法 本研究样本为10例成年骨性开患者,所有患者均采用正畸-正颌手术联合矫治.上颌采用了Le Fort I型截骨术,下颌采用了双侧升支矢状劈开截骨术(BSSO).选择患者在正畸治疗前(T1)、治疗后(T2)以及正颌手术后平均15年(T3)的头颅侧位片进行...     

用组合式矫治装置治疗前牙深覆(牙合)

目的：介绍一种组合式矫治装置及其应用。方法：该矫治方法由前牙平导板、高弹性方弓丝、第二磨牙设计支抗、后牙颌间垂直牵引等组成。结果：经临床应用２年,共６２例,效果良好。平均疗程４个月。该矫治方法的优点包括：１,前牙平（斜）导板在压低前牙和升高后牙的同时,还起到了肌激动器的作用,促使下颌骨长度与高度的发育;２,第二磨牙加入支抗系统使矫治力趋于合理,有利于牙弓的整平;３,高弹性方丝有利于牙弓的排齐和整平,同时能较好控制牙齿的位置和倾斜度;４,后牙早期颌间垂直牵引有助于后牙按一定方向萌出,并建立理想咬合关系,减小前牙覆牙合。结论：该矫治方法符合正畸生物力学原理,其疗效好,疗程短,适合于非高角型前牙深覆牙合特别是低角型深覆牙合的矫治。     

Correction of severe open bite using miniscrew anchorage

This report describes the treatment of a case of severe open bite with posterior crossbite. While treating open bite, the outcome may not always be successful with orthodontic therapy alone. In such cases, surgical therapy is often chosen to gain a stable occlusion. Skeletal anchorage systems such as miniscrews are now frequently used for correcting severe malocclusion. In this report, we treated an open bite by intruding the molars with miniscrews placed bilaterally in the interdental space between both the upper and lower posterior teeth. The active treatment period was 36 months and the patient’s teeth continued to be stable after a retention period of 36 months.     

正畸治疗安氏Ⅲ类错伴下颌偏斜的临床研究

目的探讨治疗安氏Ⅲ类错伴有单侧的后牙反、锁和单侧前牙反的牙源性下颌偏斜的有效方法。方法选择安氏Ⅲ类错伴单侧的后牙反、锁和单侧前牙反等牙源性下颌偏斜患者21例,年龄8~25岁,平均15.5岁。单侧后牙反、锁引起的下颌偏斜通过上颌扩弓、上下牙交互牵引纠正宽度不调,促使下颌自行复位;前牙反通过Ⅲ类牵引予以解除。结果 21例患者均取得良好的矫治效果,治疗后颜面对称性和咬合关系恢复正常,颏点偏斜平均减少（2.9±0.6）mm,因长期错导致的下颌骨偏斜亦得到了明显改善。结论牙源性下颌偏斜,经过合理正畸治疗,随着单侧后牙反、锁及单侧前牙反的解除可得到明显的改善。     

The overbite and intraoral mandibular distraction osteogenesis.

PURPOSE: The purpose of this study was to quantify the overbite reduction in skeletal Angle Class II malocclusions and discuss the management of the overbite during and after intraoral distraction of the mandible, and during orthodontic treatment with fixed appliances. MATERIAL AND METHODS: Cephalograms of 26 patients with an Angle Class II malocclusion and orthodontic appliances and distraction osteogenesis of the horizontal part of the mandible before (T0) and at least 1 year after treatment (T1) were evaluated. Mean age of the patients at the time of distraction was 14.6 years (range 12.8-15.9 years) and at the final registration 17.3 years (range 14.6-20.4 years). RESULTS: The overbite decreased significantly and the SpP/MP value increased significantly. The increase in the value of the Y-axis and the MP/SN angle before and after treatment was statistically insignificant. CONCLUSION: Opening of the bite during distraction of the mandible can be expected. The use of the 'floating bone' technique did not correct the overbite permanently. The patients in whom an open bite has already been treated are not ideal for mandibular lengthening by means of distraction osteogenesis.     

Treatment and posttreatment dentoalveolar changes following intrusion of mandibular molars with application of a skeletal anchorage system (SAS) for open bite correction

The skeletal anchorage system (SAS) consists of titanium anchor plates and monocortical screws that are temporarily implanted in either the maxilla or the mandible as absolute orthodontic anchorage. With SAS, anterior open bite can be improved by the counterclockwise rotation of the mandible, accompanied by the intrusion of molars. The present study was designed to evaluate treatment and posttreatment dentoalveolar changes following the intrusion of mandibular molars. Nine adult open bite patients (7 women and 2 men) successfully treated with SAS were included in the following study. The amount of intrusion, relapse, and dentoalveolar changes were measured on cephalometric radiographs, panoramic radiographs, and dental casts. The results of this study were as follows: (1) the average amount of intrusion of the mandibular first and second molars was 1.7 mm and 2.8 mm, respectively; (2) the average relapse rates were 27.2% at the first molars and 30.3% at the second molars; (3) there were no significant changes in crestal bone heights, clinical crown length, or root length; and (4) counterclockwise rotation of the mandible and decrease of anterior facial height were observed during treatment. Thus, it was concluded that SAS would be a valid modality to intrude mandibular molars for correction of open bite.