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目的    探讨镍钛（NiTi）摇椅弓附加前牙区垂直牵引对前牙开牙合畸形的治疗效果。 方法    利用NiTi摇椅弓加前牙区垂直牵引对2007—2009年在厦门市第一医院思明分院口腔科就诊的18例前牙开牙合畸形患者进行矫治,并对矫治前后的头颅侧位片进行测量分析。结果    X线头影测量显示治疗后骨骼无显著变化,下切牙伸长,下磨牙压低,上切牙及上下后牙竖直,上颌牙合平面有顺时针旋转的趋势,下颌牙合平面有逆时针旋转的趋势。开牙合间隙关闭,前后牙建立良好的咬合关系,所有病例治疗后均取得满意疗效。结论    NiTi摇椅弓加前牙区垂直牵引是治疗前牙开牙合的有效方法。     

“摇椅形”弓丝配合前牙区垂直牵引矫治开过程中对磨牙作用的生物力学研究

目的　验证应用“摇椅形”弓丝配合前牙区垂直牵引矫治开牙合畸形的效果。方法　建立包括牙周膜、牙槽骨在内的牙合的三维有限元模型 ,通过分析矫治力作用在牙体及牙周组织的应力大小及分布以及牙体的位移情况 ,认清牙齿移动的机理。结果　利用“摇椅形”弓丝配合前牙区垂直牵引矫治开牙合 |6 7畸形可以使后牙远中直立并压低 ,前牙在垂直牵引力作用下会抵消“摇椅形”弓丝对其的压低作用而牙合向移动。但要注意“摇椅形”弓丝的弧度不能太大。结论　应用“摇椅形”弓丝配合前牙区垂直牵引符合开牙合畸形治疗机理 :前牙牙合向移动 ,后牙直立及压低。可以取得与应用多曲方丝弓治疗开牙合的同样效果 ,建议临床推广应用治疗开牙合畸形患者。     

Cephalometric evaluation of the anterior open bite treatment

The present study was aimed at evaluating the treatment changes of anterior open bite malocclusion cases treated by means of the Multiloop Edgewise Arch Wire technique, which is considered one of the more effective treatment modalities for anterior open bite malocclusions. The open bite sample was composed of 16 young adults, 4 males and 12 females. The normal occlusion sample, as a controlled sample was composed of 58 young adults who had pleasing facial profiles and normal occlusions with no experience of orthodontic or prosthodontic treatment. The normal sample was subdivided by the cephalometric vertical facial relationships. Forty adults with cephalometric vertical facial relationships within the normal range of Korean standards were classified as Normal Occlusion Group 1. Eighteen adults with an increased vertical facial relationship but with normal occlusion, were classified as Normal Occlusion Group 2. Thirty-nine reference points were digitized on each film, and the computerized cephalometric analysis was obtained with 8 skeletal, 10 dentoalveolar, 17 teeth angulations, and 4 occlusal plane measurements. Treatment changes were determined by the paired t test, and the structural differences between the four groups were tabulated by the Student’s t test. The treatment changes were observed mainly in the dentoalveolar region in the upper and the lower occlusal planes, accompanied by the uprighting of the posterior teeth to the occlusal plane through the distal tipping movement of the entire dentition. After the treatment, there was a tendency for the structural feature of the open bite group to approximate those of the normal occlusion group 2. This ascertains that the treatment changes of open bite malocclusion produced by means of the multiloop edgewise arch wire technique are similar to those found in the natural dentoalveolar compensatory mechanism. (Am J Orthod Dentofacial Orthop 1999;115:29-38)     

"摇椅形"弓丝配合前牙区垂直牵引矫治开(牙合)过程中对磨牙作用的生物力学研究

目的验证应用"摇椅形"弓丝配合前牙区垂直牵引矫治开(牙合)畸形的效果.方法建立包括牙周膜、牙槽骨在内的(牙合)的三维有限元模型,通过分析矫治力作用在牙体及牙周组织的应力大小及分布以及牙体的位移情况,认清牙齿移动的机理.结果利用"摇椅形"弓丝配合前牙区垂直牵引矫治开(牙合) 67畸形可以使后牙远中直立并压低,前牙在垂直牵引力作用下会抵消"摇椅形"弓丝对其的压低作用而(牙合)向移动.但要注意"摇椅形,,弓丝的弧度不能太大.结论应用"摇椅形"弓丝配合前牙区垂直牵引符合开(牙合)畸形治疗机理:前牙(牙合)向移动,后牙直立及压低.可以取得与应用多曲方丝弓治疗开(牙合)的同样效果,建议临床推广应用治疗开(牙合)畸形患者.     

"摇椅形"弓丝配合前牙区垂直牵引矫治开过程中对磨牙作用的生物力学研究

目的验证应用"摇椅形"弓丝配合前牙区垂直牵引矫治开(牙合)畸形的效果.方法建立包括牙周膜、牙槽骨在内的(牙合)的三维有限元模型,通过分析矫治力作用在牙体及牙周组织的应力大小及分布以及牙体的位移情况,认清牙齿移动的机理.结果利用"摇椅形"弓丝配合前牙区垂直牵引矫治开(牙合) 67畸形可以使后牙远中直立并压低,前牙在垂直牵引力作用下会抵消"摇椅形"弓丝对其的压低作用而(牙合)向移动.但要注意"摇椅形,,弓丝的弧度不能太大.结论应用"摇椅形"弓丝配合前牙区垂直牵引符合开(牙合)畸形治疗机理前牙(牙合)向移动,后牙直立及压低.可以取得与应用多曲方丝弓治疗开(牙合)的同样效果,建议临床推广应用治疗开(牙合)畸形患者.     

摇椅形弓丝配合前牙区垂直牵引矫治开(牙合)时牙齿应力分布与位移趋势的研究

目的:研究"摇椅形"弓丝配合前牙区垂直牵引矫治开袷时下颌牙齿的应力分布及移动趋势.方法:建立与人体物理性能相似的1:1的全牙颌光弹模型,对模型进行临床实际应用的"摇椅形"弓丝配合前牙区垂直牵引力加载,将下颌实验模型单颗牙进行三维方向冻结切片,利用三维切力差法,计算单颗牙牙槽骨各点应力值,从而描述单颗牙牙周组织应力分布规律及运动趋势.结果:在"摇椅形"弓丝配合前牙区垂直牵引作用下,17运动趋势为整体远中移动,冠受远中向力大于根,整体龈向压低,轻微颊向移动;(6)整体远中移动,龈向压低,冠向远中舌向倾斜;(5)的移动趋势为整体远中移动,(牙合)向伸长,冠向远中旋转,近中颊向远中舌向扭转;(3)运动趋势为(牙合)向伸长,冠唇向根舌向倾斜;(2)的运动趋势为(牙合)向伸长,冠唇向根舌向转矩.结论:"摇椅形"弓丝配合前牙区垂直牵引作用于全牙弓牙齿的移动趋势符合开(牙合)的矫治机制.     

Cephalometric changes during treatment with the open bite bionator.

Lateral cephalometric radiographs of 39 patients who were treated with an open bite bionator, also known as a "bionator to close the bite," were obtained from six private orthodontic practices. Comparisons of pretreatment cephalometric values with published standards indicate that clinicians do not generally use this appliance for patients who have marked excessive anterior vertical dimension. Rather, the cases appear to be Class II with mild anterior open bites or with some indication of open bite tendency, such as a steep mandibular plane angle. Changes in cephalometric values during treatment with the appliance were compared with normal growth standards. Patients exhibited a reduction in facial convexity and overjet, reduced eruption of maxillary molars, and less of an increase in facial height than expected. The appliance appears to be effective for Class II correction in patients who require control or improvement of moderately excessive vertical dimension.     

Cephalometric comparison of adult anterior open bite treatment using clear aligners and fixed appliances

Objectives:To compare fixed appliances and clear aligner therapy in correcting anterior open bite and in controlling the vertical dimension in adult patients with hyperdivergent skeletal patterns.Materials and Methods:In this retrospective study, two treatment groups of adult (≥18 years old) hyperdivergent patients (mandibular plane angles of ≥38°) with anterior open bites were included: 17 fixed appliance patients and 36 clear aligner patients. Thirteen cephalometric measurements representing the vertical dimension were reported for each group. A two-sample t-test was used to assess differences in changes in mandibular plane angle and overbite between the two treatment groups.Results:There were no statistical differences found in the magnitude of overbite correction and the changes in any of the cephalometric measurements for vertical control. The clear aligner group showed a slightly greater amount of lower incisor extrusion (P = .009). The main mechanism of open bite correction was similar between the two treatment groups and was accomplished through retroclination of the upper and lower incisors while maintaining the vertical position of the upper and lower molars.Conclusions:Cephalometric comparison of anterior open bite correction and changes in the mandibular plane angle associated with use of clear aligners and fixed appliances did not demonstrate statistically significant differences in adult hyperdivergent patients.     

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.     

Orthodontic treatment of anterior open bite

OBJECTIVE: To review the currently available treatment options of anterior open bite. METHODS: Search all major dental journals and literature on treatment and management of anterior open bite. Medline search (1960-2006). Literature and data on treatment and management of anterior open bite with keywords 'open bite', 'anterior open bite', 'orthodontic treatment', 'long face', 'vertical dentoalveolar problem' and 'vertical skeletal problem'. RESULTS: Over 50 articles were found and relevant information and data were reviewed by the authors. It was found that the multifactorial nature of anterior open bite makes its management difficult and various treatment modalities are being used. Clinicians must be able to diagnose the problem and choose the best treatment. CONCLUSION: Successful treatment of anterior open bite greatly relies on both diagnosis and therapeutics. Although there are many different treatment modalities available, stability after treatment is still a critical issue as evidence on long term stability of various treatment options is lacking. Thus, clinicians should pay more attention during retention phase and long-term studies on post-treatment changes and stability should be encouraged.     

Cephalometric and clinical diagnoses of open bite tendency

Pretreatment lateral cephalometric radiographs of patients between 10 and 16 years of age were searched for persons who met criteria commonly used for identifying patients with "open bite tendencies." Results indicate that different measures of open bite tendency identify different patients. Of 50 patients with sella-nasion-mandibular plane angles greater than 40 degrees, only 11 had upper facial height/lower facial height ratios less than 0.70; of 50 patients who had occlusal plane-mandibular plane angles greater than 22 degrees, only 15 had posterior facial height/anterior facial height ratios of less than 0.58. Of the 250 patients who exhibited some well-accepted cephalometric indication for excessive vertical dimension, only 13% had actual anterior open bites. When clinicians ranked their own patients according to the difficulty in controlling excessive vertical growth during treatment, measurements such as the mandibular plane angle, upper to lower facial height ratio, and anterior to posterior facial height ratio did not predict treatment responses.     

前牙开(牙合)不同矫治设计的初步研究

目的 探讨前牙开不同的矫治设计和矫治技术的选择。材料方法 选择13例(男性1人,女性12人)12～45岁前牙开(牙合)畸形患者,对矫治设计和矫治技术进行总结分析,并对矫治前后的头颅侧位片进行测量分析,比较使用不同方法矫治前后的变化。结果 所有病例治疗后均取得满意疗效。其中1例为不拔牙矫治,4例为拔除第二或第三磨牙,8例为拔除双尖牙。不拔牙或拔除后牙矫治患者均采用MEAW矫治技术,通过直立磨牙、伸长切牙来改变平面、关闭开;拔除双尖牙患者采用滑动矫治技术通过内收前牙、前移磨牙来矫治开。结论 在正确诊断的前提下,结合病因治疗、选择适当的矫治技术是正畸治疗前牙开畸形成功的关键。     

磨牙前倾弯治疗前牙开(牙合)畸形的临床效果评价

目的 开拾畸形在临床治疗上难度较大，治疗方法较单一、局限、疗程长、矫治效果不确定，本文目的在于了解应用前倾弯矫治前牙开He时的矫治效果。方法 对5例前牙开He的患者应用前倾弯进行矫治，通过分析矫治前后X线头颅定位侧住片，评价前倾弯在矫治前牙开He畸形的效果。结果 发现矫治过程中，第一磨牙明显近中倾斜；矫治前后全面高、前后面高有显著性变化；上颌切牙至腭平面、下颌切牙至下颌平面的垂直距离明显增加；下颌第一磨牙至下颌平面的角度明显变大，说明在矫治后上下切牙伸长并向舌侧移动。结论 前倾弯治疗开He主要是通过前牙的伸长和舌侧移动来达到建立覆He的目的，而后牙不仅不能直立，而且会更加近中倾斜，从而使He平面不能改变，而使开He的矫治效果不稳定。