Relapse following surgical treatment of anterior open bite

From a series of 40 cases of anterior open bite treated surgically by Le Fort I osteotomy, four cases relapsed. The nature of the relapse was investigated by computer aided analysis of lateral cephalometric radiographs. The location, aetiology and possible prevention of the relapse is discussed for each case.     

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.     

Stability of anterior open bite nonextraction treatment in the permanent dentition.

This study cephalometrically evaluated the long-term stability of anterior open bite nonextraction treatment in the permanent dentition after a mean period of 5 years. The experimental group consisted of 21 patients who had undergone orthodontic treatment with fixed appliances from whom cephalometric headfilms were obtained at the pretreatment, posttreatment, and postretention stages. Two control groups were used. The first, with ages comparable with the experimental group before treatment, was used only to characterize it. The second control group, with normal occlusion, was longitudinally followed for a period comparable with the posttretention period and was used to compare the changes between groups during this period. The differences between the observation stages in the experimental group were analyzed with paired t tests, and the postretention changes were compared with the changes of the second control group with independent t tests. A statistically significant decrease of the obtained anterior overbite was demonstrated at the end of the postretention period. The primary factor that contributed to the overbite decrease was the smaller vertical development of the maxillary and mandibular incisors in the postretention period. Neither the pretreatment anterior open bite amount nor the magnitude of correction was associated with the long-term overbite decrease. However, 61.9% of the sample had a clinically stable open bite correction.     

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。     

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)     

A ten-year follow-up case report following surgical correction of anterior open bite

A case is reported whereby an anterior open-bite was treated with the Köle osteotomy in an adult Chinese girl. This study documents cephalometrically the post-treatment changes occurring in the dento-alveolar complex over a ten year follow-up period and describes the possible mechanisms contributing to the remarkable stability of the open-bite correction.     

Combined surgical and orthodontic management of anterior open bite using corticotomy.

Two cases of dentoalveolar abnormality have been presented that were treated successfully in a relatively short time by using the combined efforts of the oral surgeon and orthodontist. Although corticotomy has limited applications, it has a place in the armamentarium of the orthognathic surgeon.     

The causes,diagnosis and treatment of anterior open bite

Anterior open bite has multiple aetiologies, but can be broadly described as being dental or skeletal in origin. Accurate differentiation is essential in determining the appropriate treatment plan: dental open bites may close spontaneously in the growing patient and are generally amenable to orthodontic treatment, whereas skeletal open bites frequently worsen with growth and usually require a combination of orthodontics and orthognathic surgery. The incidence of post-treatment relapse is high, making these malocclusions a challenge to treat successfully.     

前牙开畸形颅面形态的分类研究

目的　对前牙开畸形进行分类研究 ,为临床诊断和治疗提供参考。方法　随机选取116例恒牙期前牙开患者 ,借助计算机X线头影测量技术对其颅面软硬组织及气道结构进行测量 ,综合运用多种现代多元统计方法 ,对开畸形的颅面形态进行分类。结果　对年龄、性别、颅面特征等 15 6项指标经聚类和主成分分析精简为 30个变量 ,再通过因子分析提取出 4个因子 (下颌旋转因子、面高因子、牙骨矢状因子和上颌旋转因子 )。采用逐步聚类法对 116例患者的 4个因子得分进行聚类分析 ,将前牙开畸形这一群体分为牙齿槽型开、下颌顺时针旋转型开、长面型开、上颌逆时针旋转型开和骨性Ⅲ类开 5类并归纳出可供临床使用的简单分类方法。结论　对前牙开畸形进行分类在诊断和矫治设计中起着重要作用。