比较2种部位种植钉支抗推上颌磨牙向远中移动的效果

目的：比较2种位置的微种植钉支抗推磨牙向远中的临床效果。方法：选择安氏Ⅱ类错25例,男7例,女18例,年龄15～29岁,平均22．58岁,牙列轻中度拥挤,面型较好,无明显前突。实验组（n ＝12）于颊侧第一磨牙近中颊根上方颧牙槽嵴处植入微螺钉种植体;对照组（n ＝13）于上颌第一磨牙与第二前磨牙牙根之间植入微螺钉种植体。推磨牙向远中,推力2．5 N。通过临床评价和对比2组矫治前后的头颅侧位定位片评价其治疗效果差异。结果：实验组和对照组微种植体首次植入成功率分别为100％（26/26）和87．5％（21/24）。治疗后上颌磨牙分别后移（2．91±0．96）mm 和（2．29±0．66）mm（P ＞0．05）。实验组磨牙压低的作用优于对照组,切牙唇倾的副作用小于对照组,切牙压入的作用优于对照组。结论：颧牙槽嵴处的微种植钉支抗推磨牙向远中移动较传统颊侧种植钉支抗对磨牙的垂直向压入及对抗切牙唇倾的效果好。     

Comparison between direct vs indirect anchorage in two miniscrew-supported distalizing devices

Objective:To compare two distalizing devices supported by palatal miniscrews, the MGBM System (MGBM) and the Distal Screw appliance (DS), in dental Class II patients.Materials and Methods:Pretreatment (T1) and postdistalization (T2) lateral cephalograms of 53 Class II malocclusion subjects were examined. MGBM consisted of 29 patients (16 males, 13 females) with a mean pretreatment age of 12.3 ± 1.5 years; DS consisted of 24 patients (11 males, 13 females) with a mean pretreatment age of 11.3 ± 1.2 years. The mean distalization time was 6 ± 2 months for MGBM and 9 ± 2 months for DS. Initial and final measurements and treatment changes were compared by means of a Student’s t-test.Results:Maxillary superimpositions showed that the maxillary first molar distalized an average of 5.5 mm in the MGBM and 3.2 mm in the DS between T1 and T2; distal molar tipping was greater in the MGBM (10.3°) than in the DS (3.0°). First premolar showed a mean mesial movement of 1.4 mm, with a mesial tipping of 4.4° in the MGBM; on the contrary, first premolar showed a distal movement of 2.2 mm, with a distal tipping of 6.2°, in the DS.Conclusions:The MGBM system resulted in greater distal molar movement and less treatment time, resulting in more efficient movement than was associated with the DS; DS showed less molar tipping during distalization.     

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.     

控根辅弓在推磨牙远移中的应用

目的探讨控根辅弓联合Ⅱ类牵引,应用于口内弓上施以镍钛簧推磨牙远移的临床效果。方法21例安氏Ⅱ类错牙合病例采用口内弓设置NiTi簧,辅以反向控根辅弓及Ⅱ类牵引推磨牙往远中,治疗前后均摄X线头颅侧位片及治疗前后口内外X线片。结果1.0~4.2个月(平均2.6个月)磨牙关系达到中性或偏近中,上切牙无明显唇倾、磨牙略有伸长。结论控根辅弓配合Ⅱ类牵引的口内弓推磨牙往远中,方法简便易行,并能较好地控制好前牙唇倾。     

Long-term stability of miniscrew anchored maxillary molar distalization in Class II treatment

ObjectiveTo investigate treatment stability of miniscrew-anchored maxillary distalization in Class II malocclusion.Materials and MethodsThis retrospective study included a distalization (n = 19) and a control (n = 19) group; a patient group with minor corrections served the control. Lateral cephalograms of 38 adult patients were taken before (T0), immediately after (T1), and 3–4 years after (T2) treatment. Horizontal and vertical movement and tipping of the maxillary first molars (U6) and central incisors (U1) were measured along with skeletal craniofacial parameters at three time points to compare the two groups regarding the achieved treatment effects and their stability.ResultsTotal arch distalization therapy led to 4.2 mm of distal movement of U6 without distal crown tipping (0.6° of axis change) and 3.3° of occlusal plane steepening. Over an average retention period of 42 months, maxillary total arch distalization provided high stability of treatment results, showing the same amount of mesial movement (0.7 mm) as the control group.ConclusionsIn Class II treatment, miniscrew-anchored maxillary total arch distalization can provide stable distal movement of the maxillary first molars and central incisors.     

Maxillary molar distalization with miniscrew-supported appliances in Class II malocclusion: A systematic review

Objectives:To evaluate the quantitative effects of miniscrew supported appliances for maxillary molar distalization in Class II malocclusion.Materials and Methods:The systematic search included MEDLINE, EMBASE, CINAHL, PsychINFO, Scopus, and key journals and review articles. The date of the last search was January 30, 2017. Methodological quality of the retrospective studies was graded by means of the Quality Assessment Tool for Quantitative Studies, developed for the Effective Public Health Practice Project (EPHPP) and prospective studies by means of Newcastle–Ottawa Scale.Results:In total, 298 studies were identified for screening, and 14 studies were eligible. The Quality Assessment Tool for Quantitative Studies rated all of the four included retrospective studies as moderate. The Newcastle–Ottawa Scale rated seven studies as high quality and three studies as low quality. The mean molar distalization values varied from 1.8 mm to 6.4 mm. Mean distal tipping of molars varied from 1.65° to 11.3°. The mean distal movement of premolars and incisors varied from 1.75 mm to 5.4 mm and 0.1 mm to 2.7 mm, respectively.Conclusions:Miniscrew-supported appliances are effective in molar distalization with distal movement of premolars with minimal anchorage loss and distal tipping of the molar teeth.     

改良双轨道装置GMD推磨牙远移的临床应用

目的：探讨一种改良推磨牙远移装置的临床效果。方法：选择AngleⅡ^错[牙合],上颌轻度前突或牙列拥挤,下颌正常或轻度后缩病例,第一期应用Nance托NiTi方丝多曲弓推磨牙远移矫治。第二期使用直丝弓矫治器矫治,治疗前后进行X线头影测量分析。结果：应用该矫治法解决了非拔牙矫治中间隙预备问题,为磨牙中性殆的建立创造了条件。结论：Nance托联合多曲NiTi方弓推磨牙远移是一种方法简便、安全可靠,有效的非患者依从性矫治方法。     

Upper molar distalization: a critical analysis

Traditional upper molar distalization techniques require patient co-operation with the headgear or elastics. Recently, several different intraoral procedures have been introduced to minimize the need for patient co-operation. This article reviews the appliances currently available for maxillary molar distalization and critically analyses their dentoalveolar and skeletal effects.     

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提要：推磨牙远中移动是消除牙列轻、中度拥挤，开拓间隙，改善安氏Ⅱ类错牙合磨牙关系的方法之一。本文就推磨牙远中移动技术的研究进展做一综述，并探讨磨牙远移矫治器的适用范围。     

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.     

Essix®-based molar distalization appliance

Abstract

A new design of molar distalization appliance and its fabrication are described in this article. This case report illustrates distal movement of mandibular molars with negligible loss of anterior anchorage. This new vacuum-formed Essix appliance can be a reasonable alternative to conventional appliances.     

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。     

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.     

Anatomical limitations and factors influencing molar distalization

ObjectivesTo analyze the anatomical limitations and characteristics of maxillary and mandibular retromolar regions affecting molar distalization using cone-beam computed tomography (CBCT).Materials and MethodsA total of 120 qualifying patients were classified into equal groups of skeletal Class II and Class III and stratified by vertical growth pattern, age, sex, and third molar presence. The available distance along the axis of distalization and cortical bone thickness (CBT) were measured in the maxillary and mandibular retromolar regions of Class II and Class III patients, respectively. One-way analysis of variance was used to examine the effects of the factors on the measured data.ResultsThe minimum available distance of the Class II maxilla was observed at a level 3 mm from the cementoenamel junction (CEJ), while that of the Class III mandible was at a level 9 mm from the CEJ. The average available distance at the limit level was 4.06 ± 1.93 mm in the Class II maxilla, and the average corresponding CBT was 1.00 mm. The average available distance at the limit level in the Class III mandible was 2.80 ± 1.96 mm, and the corresponding CBT was 2.24 mm. In both skeletal Class II and Class III patients, hyperdivergent groups had the least available distance for molar distalization.ConclusionsThe limit for available distance in the Class II maxilla is closer to the coronal level, while that of the Class III mandible is closer to the apical level. A hyperdivergent growth pattern in a patient is indicative of less potential for molar distalization. Axial slices of CBCT images provide valuable evaluation for molar distalization regarding limit levels.     

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目的研究Sliding jig配合颌间牵引远移磨牙的治疗效果。方法选择2005-2006年于中国医科大学口腔医学院正畸科就诊的15例Ⅰ类骨骼关系或轻度骨性错畸形、无须拔牙矫治患者,其中安氏Ⅱ类畸形7例、Ⅲ类畸形8例,分别行Sliding jig配合安氏Ⅱ类、Ⅲ类颌间牵引推磨牙向后,并与单纯牵引患者进行对比,通过头影测量确定磨牙的移动量,分析Sliding jig治疗产生的牙齿及骨骼效应。结果Sliding jig配合颌间牵引能达到安氏Ⅰ类关系,磨牙远移(3.14±1.07)mm;单纯颌间牵引磨牙远移(0.91±0.55)mm,两组比较差异有统计学意义(P<0.01)。头影测量结果比较,骨骼改变无明显差异。结论Sliding jig与颌间牵引等方法的联合应用可有效地将磨牙向远中移动,加快磨牙关系的调整。     

无托槽隐形矫治技术推磨牙向远中牙齿移动类型的研究

目的研究无托槽隐形矫治技术推磨牙向远中牙齿移动的类型。方法选取2016年3月至2018年10月于首都医科大学附属北京口腔医院正畸科就诊的患者58例,所有患者均采用无托槽隐形矫治技术推磨牙向远中。治疗前后均拍摄头颅侧位片及曲面体层片,分别测量上下颌第一、二磨牙远移量及牙长轴倾斜度。结果治疗前后上下颌第一、二磨牙到翼肌垂直平面(PTV)的距离比较,差异均有统计学意义(均P<0.05);治疗后上颌第一磨牙向远中移动(1.28±1.24)mm,上颌第二磨牙向远中移动(2.47±1.77)mm,下颌第一磨牙向远中移动(1.77±1.20)mm,下颌第二磨牙向远中移动(2.83±1.39)mm。治疗前后曲面体层片中的上下颌第一、二磨牙牙长轴与双侧眶下缘基准平面所成角比较,差异均无统计学意义(均P>0.05)。治疗前后头颅侧位片中上颌磨牙与前颅底平面(SN平面)所成角及下颌磨牙与下颌平面(MP平面)所成角比较,差异均无统计学意义(均P>0.05)。结论本研究初步证实了无托槽隐形矫治技术推磨牙向远中时磨牙是整体移动的,而非倾斜移动。     

“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。     

无托槽隐形矫治技术推磨牙向远中的研究进展

无托槽隐形矫治器在实现所有类型牙齿移动上,推磨牙向远中的效率最高.但临床中容易出现磨牙远中倾斜,支抗丧失等问题.该文就隐形矫治推磨牙向远中的适应证、临床疗效、远移效率、支抗设计等4个方面进行综述,为临床提供参考.