“摆”式矫治器远中移动上颌磨牙的疗效分析

目的研究"摆"式矫治器远中移动磨牙的效果以及其对面部骨骼和上颌牙齿的影响。方法选择处于替牙期或恒牙早期,上颌牙列轻中度拥挤,磨牙远中关系的病例25例。采用"摆"式矫治器远中移动上颌磨牙。以X线头影测量分析为测定手段。结果①上颌第一、二磨牙均发生了远中倾斜移动;②上颌第一前磨牙发生了近中倾斜移动,上中切牙发生了唇向倾斜移动;③在垂直向上,第一磨牙位置无明显变化,上颌第二磨牙伸长。④前牙覆盖增加,覆减小;⑤MP-SN和前下面高(ANS-Me)增加。结论①"摆"式矫治器可以有效的远中移动上颌磨牙;②"摆"式矫治器主要影响上颌牙齿,而对面部骨骼影响较小;③"摆"式矫治器在远中移动磨牙的同时伴随有上颌磨牙远中倾斜和上颌前部支抗丧失。     

Pendulum矫治器推上颌第一磨牙向远中时对上颌第二磨牙的影响

本研究旨在了解采用Pendulum(摆式)矫治器使上颌第一磨牙向远中移动时对上颌第二磨牙的影响。 收集38例在福岗齿科大学矫正齿科及私人诊所就诊,并采用Pendulum(摆式)矫治器远中移动上颌第一磨牙的患者,分为3组:其中19例上颌第二磨牙未萌出(未萌组),9例已萌出(已萌组),10例已拔除(拔除组)。采用头影测量片和研究模型分别比较以上3组在治疗前后上颌磨牙和支抗单元的变化。     

Distal-Jet 矫治器远中移动上颌磨牙的疗效

目的:评价Distal-Jet矫治器远中移动上颌磨牙的疗效。方法:应用Distal-Jet矫治器对12例平均年龄为12.3岁,由于上颌磨牙前移所致的安氏Ⅱ类错患者进行治疗,通过远中移动磨牙前后的头影测量分析和模型测量分析评价其远中移动磨牙的疗效。结果:①磨牙平均向远中移动(3.6±0.75)mm,牙冠远中倾斜(3.5±3)°;②第一前磨牙近中移动(2.1±1.7)mm,牙冠近中倾斜(3.1±2.57)°,前牙覆盖增加(1.47±1.76)mm;③磨牙和第一前磨牙分别伸长(0.39±0.46)mm和(0.43±0.61)mm;④双侧上颌第一磨牙中央窝间宽度增加(2.8±1.1)mm。结论:Distal-Jet矫治器能有效地整体远中移动上颌磨牙,但也会引起少量前磨牙的近中移动及牙冠近中倾斜。     

摆型矫治器远中移动上颌磨牙矫治安氏II类错

目的　研究改良摆型矫治器对牙和面部骨骼结构的影响。方法　选择安氏Ⅱ类错16例 ,其中女 13例 ,男 3例 ,年龄 9 3～ 2 2 8岁 ,平均 13 6岁。采用摆型磨牙远中移动矫治器治疗。摆型矫治器推磨牙向远中的疗程为 1～ 6个月 ,平均 3 7个月。以X线头影测量分析和模型测量分析为测定手段。结果　①每侧磨牙平均向远中移动 3 5 9mm ,主要为磨牙向远中倾斜移动。②切牙牙冠平均向近中移动 3 2 8mm ,主要为切牙的近中倾斜移动 ,前牙的覆盖增加 ,达 1 5 6mm。③牙列出现较大的间隙 ,双侧分别达 6 70mm和 6 5 9mm。④磨牙垂直向移动较少 ,推磨牙后 ,磨牙平均伸长仅0 6 9mm。⑤磨牙区、双尖牙区与尖牙区的宽度均增加 ,分别达 2 0 3mm、1 6 6mm和 1 10mm。⑥摆型矫治器对面部骨骼结构无明显的直接影响。结论　摆型矫治器能有效地远中移动上颌磨牙 ,快速矫正磨牙关系。但也可导致磨牙倾斜及切牙唇向倾斜移动 ,临床治疗中应予注意     

改良式摆型矫治器远中移动上颌磨牙的疗效分析

目的 评价改良式摆型矫治器远中移动上颌磨牙的疗效。方法 选择14例牙性安氏Ⅱ类错的患者,应用改良式摆型矫治器远移上颌第一磨牙,通过矫治前和磨牙远移到位后的X线头影测量分析评价其疗效。结果 磨牙平均向远中移动3.85mm,牙冠远中倾斜3.22°;切牙近中倾斜移动2.08mm,覆盖增加1.68mm。结论 改良式摆型矫治器能有效地整体远中移动上颌磨牙,快速矫正磨牙关系,但也会引起少量的支抗丧失和切牙唇向移动。     

改良蛙式矫治器远中移动上颌磨牙临床初探

目的：比较改良蛙式矫治器与摆式矫治器远中移动上颌磨牙的临床疗效。方法：将20例需远中移动上颌磨牙病例分成两组,改良蛙式矫治器组8例,摆式矫治器组12例。对矫治前及磨牙移动至中性关系后的头颅定位侧位片进行测量,并通过成组设计的t检验分析两组牙颌面形态变化的差异。结果：①改良蛙式矫治器组与摆式矫治器组在上颌第一磨牙远中移动距离、远中倾斜程度、矫治时间及速率上无明显统计学差异（P〉0．05）。②改良蛙式矫治器组上颌第二前磨牙远中移动1．83±1．21mm,远中倾斜7．50°±7．07°摆式矫治器组上颌第二前磨牙近中移动1．79±2．44mm,近中倾斜4．33°±3．73°两组问有明显统计学差异（P〈0．01）。③改良蛙式矫治器组上颌中切牙近中移动0．17±0．52mm,远中倾斜0．580±1．74°摆式矫治器组上颌中切牙近中移动2．96±2．46mm,近中倾斜7．08°±7.48°两组问有明显统计学差异（P〈0．05）。结论：改良蛙式矫治器能不依赖患者配合,有效地远中移动上颌磨牙,并且相比较摆式矫治器能有效地减少前牙支抗丧失,适用于安氏Ⅱ类错胎畸形的矫治。     

改良"摆"式矫治器推磨牙远移12例分析

目的:研究改良"摆"式矫治器对(牙合)和面部骨骼结构的影响.方法:安氏Ⅱ类错(牙合)12例,采用改良"摆"式矫治器治疗.摆式矫治器推磨牙向远中的疗程为2～4个月.进行X线头影测量分析和模型测量分析.结果:①每侧磨牙平均向远中移动2.75 mm,主要为倾斜移动.②切牙牙冠平均向近中移动2.06 mm,主要为近中倾斜移动,前牙覆盖增加1.30 mm.前牙唇倾增加1.9°.③摆式矫治器改良后对面部骨骼结构无直接影响.结论:摆式矫治器能有效地远中移动上颌磨牙,快速矫正磨牙关系,但也可导致磨牙远中倾斜及切牙唇向倾斜移动.     

弹弓式磨牙远移器治疗上颌第一恒磨牙异位萌出

目的评价使用弹弓式磨牙远移器治疗第一恒磨牙异位萌出的临床效果。方法选择替牙期不可逆性第一恒磨牙异位萌出患者8例,男3例,女5例,年龄6.8~9.5岁,平均8.6岁。所有病例均存在不同程度的第二乳磨牙远中根吸收。采用弹弓式磨牙远移器标准型或简化型矫治器治疗,推第一恒磨牙向远中移动,使第一恒磨牙与第二乳磨牙远中面脱离接触并最终萌出到正常位置。结果所有病例第一恒磨牙牙冠均向远中移动并竖直,与第二乳磨牙脱离接触。治疗时间1.5~4.0个月,平均2.2个月。结论弹弓式磨牙远移器是治疗第一恒磨牙异位萌出的有效方法。     

早期远移磨牙矫治上颌第二前磨牙阻生的临床研究

目的:探讨远中移动上颌第一磨牙,结合直丝弓矫治伴有第二前磨牙阻生的II类错畸形的有效性。方法:选取处于替牙晚期、上颌中重度拥挤的24例患者,采用活动矫治器单侧或双侧远移上颌第一磨牙,开辟间隙并进行第二期固定矫治;统计学分析治疗前后的X线头影测量结果,评估临床疗效。结果:上颌第一磨牙平均远中移动4.5 mm,两侧磨牙和尖牙达到I类关系,上颌前牙唇倾度增加。结论:早期远中移动上颌第一磨牙并结合直丝弓技术可促进第二磨牙正常萌出。     

第二磨牙存在状态对远移第一磨牙效果的临床研究

目的分析上颌第二磨牙的不同存在情况对口外弓远移上颌第一磨牙的影响,并评价临床疗效。方法临床选取磨牙Ⅱ类Ⅰ分类关系口外弓远移磨牙病例30例,其中拔除上颌第二磨牙7例,平均年龄18.4岁;上颌第二磨牙未萌13例,平均年龄11.7岁;上颌第二磨牙已萌10例,平均年龄16.9岁。根据治疗前后牙列模型及头颅侧位片,测量分析磨牙远移总量、总时间、下磨牙近移量等指标,评价临床疗效。结果拔除组上颌第一磨牙远移速度最快;拔除组磨牙的远中倾斜显著小于已萌组;3组中上颌第二前磨牙向近中移动、上前牙轴倾度增加不明显,且拔除组小于其他2组。结论在严格把握适应证的前提下,对于某些特定病例,拔除上颌第二磨牙可以有效提高疗效和简化疗程。     

Dentoalveolar and skeletal changes associated with the pendulum appliance.

The purpose of the study was to examine the dentoalveolar and skeletal effects of the pendulum appliance in Class II patients at varying stages of dental development and with varying facial patterns (high, neutral, and low mandibular plane angles). Specifically, the amount and nature of the "distalization" of the maxillary first molars and the reciprocal effects on the anchoring maxillary first premolars and incisors were studied, as were skeletal changes in the sagittal and vertical dimensions of the face. Pretreatment and posttreatment cephalometric radiographs obtained from 13 practitioners were used to document the treatment of 101 patients (45 boys and 56 girls). The average maxillary first molar distalization was 5.7 mm, with a distal tipping of 10.6 degrees. The anchoring anterior teeth moved mesially, as indicated by the 1.8-mm anterior movement of the upper first premolars, with a mesial tipping of 1.5 degrees. The maxillary first molars intruded 0.7 mm, and the first premolars extruded 1.0 mm. Lower anterior facial height increased 2.2 mm; there was no significant difference in lower anterior facial height increase between patients of high, neutral, or low mandibular plane angles. In patients with erupted maxillary second molars, there was a slightly greater increase in lower anterior face height and in the mandibular plane angle and a slightly greater decrease in overbite in comparison to patients with unerupted second molars. Similar findings were observed in patients with second premolar anchorage versus those with second deciduous molar anchorage. The results of this study suggest that the pendulum appliance is effective in moving maxillary molars posteriorly during orthodontic treatment. For maximum maxillary first molar distalization with minimal increase in lower anterior facial height, this appliance is used most effectively in patients with deciduous maxillary second molars for anchorage and unerupted permanent maxillary second molars, although significant bite opening was not a concern in any patient in this study.     

Intraoral maxillary molar distalization

OBJECTIVE: To evaluate the maxillary molar distalization and anchorage loss in two groups, one before (MD 1 group) and one after (MD 2 group) eruption of second maxillary molars. MATERIALS AND METHODS: After a sample size calculation, 20 patients were recruited for each group from patients who fulfilled the following criteria: no orthodontic treatment before distal molar movement, Class II molar relationship defined by at least end-to-end molar relationship, space deficiency in the maxilla, and use of an intra-arch NiTi coil appliance with a Nance appliance to provide anchorage. Patients in the MD 1 group were without any erupted second molars during the distalization period, whereas in the MD 2 group both the first and second molars were in occlusion at start of treatment. The main outcome measures to be assessed were: treatment time, ie, time in months to achieve a normal molar relation, distal movement of maxillary first molars, and anterior movement of maxillary incisors (anchorage loss). The mean age in the MD 1 group was 11.4 years; in the MD 2 group, 14.6 years. RESULTS: The amount of distal movement of the first molars was significantly greater (P < .01) and the anchorage loss was significantly lower (P < .01) in the group with no second molars erupted. The molar distalization time was also significantly shorter (P < .001) in this group, and thus the movement rate was two times higher. CONCLUSIONS: It is more effective to distalize the first maxillary molars before the second molars have erupted.     

Evaluation of maxillary molar distalization with the distal jet: a comparison with other contemporary methods

Maxillary molar distalization is an increasingly popular option for the resolution of Class II malocclusions. This communication describes the effects of one particular molar distalizing appliance, the distal jet, in a sample of 20 consecutively treated and growing subjects (11 females, nine males; mean starting age of 13) and compares these effects with those of similar devices. Pre- and postdistalization cephalometric radiographs and dental models were analyzed to determine the dental and skeletal effects. The distal jet appliances were constructed using a biomechanical couple to direct the distalizing force to the level of the maxillary first molar's center of resistance. The distal jet was the only appliance used during the distalization phase of treatment. Examination of the cephalometric tracings demonstrated that the crowns of the maxillary first molars were distalized an average of 3.2 mm into a Class I molar relationship. In the process, the first molars were tipped distally an average of 3.1 degrees, however, the amount of tipping in each case was influenced by the state of eruption of the second molar. In subjects whose second molars had erupted only to the level of the apical third of the first molar roots, distal tipping was almost twice that seen when the second molar had completed their eruption. Anchorage loss measured at the first premolars averaged 1.3 mm, but the crowns tipped 3.1 degrees distally because of the design of the appliance. The maxillary incisors were proclined an average of 0.6 degrees with minimal effect on the mandibular plane angle and lower facial height. This study suggests that the distal jet appliance effectively moves the maxillary molars distally into a Class I molar relationship with minimal distal tipping, however, some loss of anchorage is to be expected during this process. The distal jet appliance compares favorably with other intraoral distalization devices and with mechanics featuring mandibular protraction for the resolution of patients with Class II, despite the fact that these types of mechanics address different jaws.     

钟摆矫治器联合颊侧推簧远移磨牙的疗效分析

目的：评价钟摆矫治器联合颊侧推簧远移磨牙的疗效.方法：选择40例牙性安氏Ⅱ类错（牙合）畸形的患者,随机均分为两组：钟摆矫治器联合颊侧推簧远移磨牙组（组1）和头帽口外弓远移磨牙组（组2）,在治疗开始前（T0）和远移磨牙完成时（T1）分别拍摄侧位头影定位片进行头影测量,t检验分析组内和组间的差异.结果：组1和组2远移磨牙的平均距离分别是（4.48±1.63） mm、（2.68±1.71） mm;组1和组2磨牙远中倾斜的平均角度分别是5.46°±3.23°、1.02°±2.16°;组1上颌中切牙未发生明显的唇倾和唇向移位,而组2上颌中切牙发生了较为明显的腭侧移位.结论：钟摆矫治器联合颊侧推簧远移磨牙可有效防止前牙支抗的丧失、控制磨牙的近中颊侧旋转.     

Efficiency of a pendulum appliance for molar distalization related to second and third molar eruption stage.

A modified pendulum appliance, including a distal screw and special preactivated pendulum springs (built-in straightening activation and toe-in bending), was used for bilateral maxillary molar distalization in 36 adolescent patients in various stages of the molar dentition. The patients were divided into 3 groups (PG 1-3) according to the stage of eruption of their second and third molars. In PG 1 (18 patients), eruption of the second molars had either not yet taken place or was not complete. In PG 2 (15 patients), the second molars had already developed as far as the occlusal plane, with the third molars at the budding stage. In PG 3 (3 patients), germectomy of the wisdom teeth had been carried out, and the first and second molars on both sides had completely erupted. Analysis of cephalograms to identify any changes in the sagittal plane showed that, in the direction of distalization, a tooth bud acts on the mesial neighboring tooth like a fulcrum, and that tipping of the first molars in patients in whom the second molar was still at the budding stage was thus greater. In patients whose second molars had erupted completely, the degree of tipping was greater again when a third molar bud was located in the direction of movement. After previously completed germectomy of the wisdom teeth, almost exclusively bodily distalization of both molars is possible, even without bands being applied to the second molars. However, if the first and second molars are distalized simultaneously with a pendulum appliance, the duration of therapy will be longer, greater forces will have to be applied, and more anchorage will be lost. Statistical analysis of the results of dental-angular measurements showed significant differences in the degree of molar tipping and reciprocal incisor protrusion. The degree of distal tipping of first molars was less in patients with erupted second molars (PG 2 and PG 3) than in those whose second molars were not yet erupted (PG 1). For instance, the measured angles were 0.9 degrees +/- 3.43 degrees (to the palatal plane) and 0.8 degrees +/- 3.4 degrees (to the anterior cranium floor) in PG 2, and -0.33 degrees +/- 0.58 degrees and 0.67 degrees +/- 2.08 degrees, respectively, in PG 3, contrasting with respective values of 5.89 degrees +/- 3.74 degrees and 5.36 degrees +/- 3.49 degrees in PG 1. Tipping of erupted second molars was much more marked in PG 2 (7.92 degrees +/- 5.83 degrees to the palatal plane and 7.55 degrees +/- 5.28 degrees to the anterior cranium floor), but much less pronounced in PG 3 (2 degrees +/- 1.73 degrees to the palatal plane and 2 degrees +/- 2 degrees to the anterior cranium floor) than the corresponding movement of the second budding-stage molars in PG 1 (4.06 degrees +/- 2.15 degrees and 3.97 degrees +/- 2.27 degrees, respectively). The degree of incisor protrusion occurring reciprocally with molar distalization was much less in these patients (measured angles of 3.28 degrees +/- 1.97 degrees and 2.89 degrees +/- 2.17 degrees to the palatal plane and anterior cranium floor, respectively) than in the patients presenting different stages of the dentition (angles of 5.5 degrees +/- 3.33 degrees and 6.03 degrees +/- 4.29 degrees, respectively, in PG 2, and angles of 5.5 degrees +/- 3.28 degrees and 6.67 degrees +/- 3.09 degrees, respectively, in PG 3). Moreover, measurement of dental casts in the horizontal plane showed not only the targeted mesiobuccal rotation of both maxillary molars, but also a vestibular drift of the unbanded second molars.     

Efficiency of molar distalization associated with second and third molar eruption stage

Objective:To evaluate the efficiency of molar distalization associated with the second and third molar eruption stage.Materials and Methods:A systematic computerized database search was conducted using several databases. Adaptations of the terms molar distalization and distalizing appliances were used. The reference lists of all the selected articles were also searched for any potential articles that might have been missed in the electronic search. The data provided in the selected publications were grouped and analyzed in terms of molar distalization with respect to various eruption stages of maxillary second and third molars.Results:Out of the 13 initially identified articles only four fulfilled the final selection criteria. Three of the four studies showed no statistical significance in linear molar distalization based on the eruptive stage of the second and/or third molars, while one study found that the amount of distal movement of the first molars was significantly greater in the group with unerupted second molars. Only one study found that the amount of molar tipping that occurred as a result of distalization was related to the eruption stage of the maxillary molars. Similarly, three of the four studies found that molar distalization time was not significantly affected by eruption of the second or third molars.Conclusion:The effect of maxillary second and third molar eruption stage on molar distalization—both linear and angular distalization—appears to be minimal. This conclusion is only based on low–level of evidence clinical trials. The large variability in the outcomes should be considered clinically.     

Comparative evaluation of molar distalization therapy with erupted second molar: Segmented versus Quad Pendulum appliance

Background

There are controversial opinions about the effect of erupted second molars on distalization of the first molars. Most of the distalizing devices are anchored on the first molars, without including second molars; so, differences between sequentially distalize maxillary molars (second molar followed by the first molar) or distalize second and first molars together are not clear. The aim of the study was to compare sequential versus simultaneous molar distalization therapy with erupted second molar using two different modified Pendulum appliances followed by fixed appliances.

Methods

The treatment sample consisted of 35 class II malocclusion subjects, divided in two groups: group 1 consisted of 24 patients (13 males and 11 females) with a mean pre-treatment age of 12.9 years, treated with the Segmented Pendulum (SP) and fixed appliances; group 2 consisted of 11 patients (6 males and 5 females) with a mean pre-treatment age of 13.2 years, treated with the Quad Pendulum (QP) and fixed appliances. Lateral cephalograms were obtained before treatment (T1), at the end of distalization (T2), and at the end of orthodontic fixed appliance therapy (T3). A Student t test was used to identify significant between-group differences between T1 to T2, T2 to T3, and T1 to T3.

Results

QP and SP were equally effective in distalizing maxillary molars (3.5 and 4 mm, respectively) between T1 and T2; however, the maxillary first molar showed less distal tipping (4.6° vs. 9.6°) and more extrusion (1.1 vs. 0.2 mm) in the QP group than in the SP group, as well as the vertical facial dimension, which increased more in the QP group (1.2°) than in the SP group (0.7°). At T3, the QP group maintained greater increase in lower anterior facial height and molar extrusion and decrease in overbite than the SP group.

Conclusion

Quad Pendulum seems to have greater increase in vertical dimension and molar extrusion than the Segmented Pendulum.     

两种推磨牙向后矫治器临床应用比较

目的:评价两种推磨牙向后矫治器的主要优缺点。方法:28例磨牙前移所致的Ò类错患者,分成两组,采用两种不同的方法进行推磨牙向后矫治,¹活动法:采用口内活动矫治器辅以头帽口外牵引装置使磨牙向远中移动;º固定法:采用自制的固定矫治器(固定矫治器由改良螺旋扩大器及支抗牙所组成,Nance托将各部分连成一个整体),转动螺旋杆,使磨牙向远中移动。结果:活动法需7~9个月才能达到推磨牙向后的预期效果,并需患者高度配合,磨牙以远中倾斜移动为主;固定法只需2~215个月就能达到目标,磨牙以整体移动形式为主。结论:两种方法均能移磨牙向远中,但活动法疗程长,依从性要求高,固定法疗程短,磨牙能整体远中移动。     

A new approach in maxillary molar distalization: intraoral bodily molar distalizer.

The objectives of our study were to achieve bodily molar distalization, avoid distal tipping of molars, eliminate the need for patient cooperation (no headgear, no elastics, and no esthetic and social concern), and finally to minimize the treatment period and maximize the treatment efficiency. The study was carried out on 5 males and 10 females, a total of 15 patients. Mean age for the study group was 13.53 years. Dentally, all the patients had Class II molar relationship on both sides. The patients were in permanent dentition, second molars were erupted, and the lower dental arch was well aligned. Patients showed normal or sagittally directed growth pattern. Lateral cephalograms and study models were taken and analyzed before and after molar distalization. In the present study, in order to achieve maxillary molar distalization, a new intraoral appliance was developed. The intraoral bodily molar distalizer (IBMB) was composed of 2 parts: the anchorage unit and the distalizing unit. The anchorage unit was a wide Nance button, and the active unit consisted of distalizing springs. The springs had 2 components: the distalizer section of the spring applied a crown tipping force, while the uprighting section of the spring applied a root uprighting force on the first molars. A total of 230 g of distalizing force was used on both sides. After the distal movement of the first molars, the cephalometric results of 15 patients showed the following. Maxillary first molars were moved distally by an average of 5.23 mm (P <.001) without tipping or extrusion. Maxillary first premolars were moved 4.33 mm mesially (P <.001), tipped 2.73 degrees distally (P <.05), and extruded by 3.33 mm (P <.001). Maxillary central incisors were proclined by an average of 4.7 mm (P <.001) and tipped 6.73 degrees labially (P <.01). Model analysis showed that maxillary first molars were not rotated, and intermolar distance did not change after distal movement of molars. In conclusion, unlike most of the other molar distalization mechanics, this newly developed device achieved (1) bodily distal movement of maxillary molars and (2) eliminated dependence on patient cooperation and did not require headgear wear for molar root uprighting.