A cephalometric evaluation of anterior openbite correction with the magnetic active vertical corrector

The purpose of this study was to evaluate treatment effects of the magnetic active vertical corrector appliance (AVC) when used to treat anterior openbites in a sample of growing patients. Twenty-five patients with a mean age of 10 years 8 months underwent AVC treatment for an average of almost 8 months. They had an average of 3 mm of anterior openbite closure during the treatment period, primarily due to maxillary and mandibular molar intrusion. Additional contributions to correction of the openbite were related to maxillary incisor eruption and lingual tipping combined with mandibular incisor lingual movement. A small amount of mandibular rotation with closure of the bite and decrease in anterior force height was observed. Anteroposterior skeletal change attributed to the AVC therapy was minimal.     

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.     

“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。     

Anterior open bite correction using bite block: a case report

Several etiological factors that result in dental and/or skeletal alterations make the open bite a type of malocclusion with several treatment alternatives. Corrective fixed orthodontics in conjunction with mechanical or functional orthopedics is a routine approach in correcting this problem. However, orthosurgical treatment must never be discarded for cases with skeletal involvement. This article describes a clinical case which, despite involving skeletal aspects, was treated satisfactorily using a passive bite-block appliance in conjunction with corrective fixed orthodontics.     

"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.     

Surgical-orthodontic correction of vertical maxillary excess.

Superior repositioning of the maxilla via maxillary ostectomy has proved to be useful method of treating patients with vertical maxillary excess. It is indicated primarily in patients with lip incompetence, excessive exposure of maxillary anterior teeth, long lower facial height, contour-deficient chin, and either Class I or Class II malocclusion. We have used this procedure as routine treatment for vertical maxillary excess over the past 5 years. Timing of the surgery is not so important in non-open-bite patients, and the procedure can be done with equal success before any orthodontic intervention, during orthodontic treatment, and following all orthodontic procedures. Timing is primarily dependent upon the orthodontist's desires. Since the surgery can produce a much simpler orthodontic problem, thus reducing treatment time and allowing a better over-all result, we recommend that it be done as early in treatment as possible. Clinically, the over-all improvement in facial appearance and the predictability and stability of the results have made this a most versatile and effective procedure when carried out with good planning, proper execution and attention to detail.     

Surgical correction of vertical maxillary excess during adolescence

The timing of orthognathic surgery for the correction of dentofacial deformities is controversial. The expected predictable response to treatment in a young adult patient with vertical maxillary excess is illustrated by a case report. The concerns of the patient were addressed both morphologically and psychosocially. Postponing treatment for this group of patients until growth has finally stabilized may have far-reaching consequences, although the risk of outgrowing the correction is minimized. A retrospective study of 20 adolescents who had surgical impaction of the maxilla is reported.     

Masseter muscle adaptation following surgical correction of vertical maxillary excess

This study was designed to examine the adaptive response of the human masseter muscle following surgical correction of abnormal facial form. Biopsies of the deep surface of the anterior superficial masseter muscle were obtained from five patients demonstrating vertical maxillary excess (VME), one at the time of corrective surgery, and a second at a long-term postoperative time interval (mean, 8 months). Control biopsies were also obtained from five individuals (three cadavers and two patients) with normal dentofacial morphology. A standard regimen of histologic and histochemical staining was used to classify individual muscle fibers as either type 1, type 2, or intermediate. In both VME patients and normal subjects type 1 fibers predominated, with the control group displaying a higher percentage (50% vs. 43%). On the average, type 1 fibers also had the largest areas. Following surgery there was an increase in type 2 fibers (30% vs. 52%). Two patients receiving maxillary surgery only exhibited either no change in mean fiber area or only a slight increase. The three remaining patients who underwent concomitant maxillary and mandibular surgery all showed a significant decrease in mean fiber area. Two persons in the latter group also showed features consistent with a denervation-reinnervation process. The results of this study indicate that the human masseter responds to surgical manipulation of the jaws in a histochemically demonstrable manner, with the nature and magnitude of the response associated with the particular surgical procedure(s) performed.     

牵张成骨和引导骨再生术在垂直骨增量上的比较研究

随着种植外科的进展,大量垂直向和水平向骨增量技术得到了发展。许多种植患者存在垂直向骨量不足的问题,需要增加垂直向骨量;但垂直向骨增量相对于水平向骨增量难度比较大,预见性较差,往往易致较多的并发症;因此,垂直向骨增量技术受到了越来越多的关注。引导骨再生技术和牵张成骨术是2类较常用的垂直向骨增量技术,在临床上已得到一定的应用,本文对其在垂直向骨增量上的研究进展作一综述。     

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.     

Surgical treatment of the open bite deformity. Surgical correction of combined mandibular prognathism and open bite by oblique sliding osteotomy of the mandibular rami

Treatment of open bite deformity combined with a prognathic mandible using the oblique, sliding osteotomy of the mandibular rami has been followed for 2 1/2 years to evaluate the final outcome of the operation. The clinical and radiographic examination during the control period show a remarkably stable result with a relapse magnitude the same or slightly less than that for a straight, set-back procedure. A certain dental compensation occurs during the skeletal relapse. The thought of creating a certain "freedom-space" in the muscular fibres during the set-back procedure, thus facilitating closure of the open bite is proposed. Surgical correction of the anterior open bite today is otherwise most frequently focused on solutions with maxillary le Fort I or subapical procedures to ensure minimal influence from the jaw muscles.