下颌前倾或水平阻生磨牙的简捷快速竖直

下颌前倾或水平阻生的磨牙临床上多予以拔除,笔者对于牙列较整齐、下颌第二磨牙阻生或经正畸减数治疗后上颌第三磨牙位置正常、下颌第三磨牙阻生者仅采用与阻生磨牙相邻的磨牙作支抗牙,黏接焊接了多曲推簧的磨牙带环,推阻生磨牙向远中、牙合向移动,引导前倾或水平阻生的下磨牙竖直、萌出.结果显示前倾或水平阻生的下颌磨牙较快地被竖直、萌出到正常的牙合平面,建立良好的牙合关系,X线曲面断层片示原阻生牙冠所占的位置为正常牙槽骨组织所代替.该方法能有效地使前倾或水平阻生的下颌磨牙产生快速的远中牙合向旋转运动,具有无须手术暴露阻生磨牙颊面、操作简单、竖直时间短、患者无明显不适和创伤小等优点.     

下颌磨牙阻生的正畸治疗

目的探讨下颌前倾、水平阻生磨牙的正畸治疗方法，评估其效果。方法采用固定矫治器结合磨牙带环焊多曲推簧，推14颗水平阻生或前倾阻生的下颌磨牙远中向、[牙合]向移动，引导其竖直、萌出。结果前倾、水平阻生的下磨牙全部竖直萌出到正常的[牙合]平面并有良好的[牙合]接触关系。X线片显示原阻生牙牙冠所占位置被正常牙槽骨组织所代替。竖直治疗时间为6～12个月，平均7．4个月。结论带环焊多曲推簧的磨牙竖直技术能有效地使前倾、水平阻生的下颌磨牙产生快速的远中向、[牙合]向旋转运动，具有创伤小、操作简单、患者易适应等优点。     

2种竖直下颌前倾第二磨牙方法的比较研究

目的 介绍2种竖直下颌前倾第二磨牙的正畸方法,评价其临床疗效的差别。方法 选择12例下颌第二磨牙前倾阻生的安氏Ⅰ类错牙合患者,共16颗前倾阻生的下颌第二磨牙。按照随机化原则分成2组,每组8颗磨牙。A组采用下颌第一磨牙带环焊支架的方法,通过橡皮链连接支架与下颌第二磨牙牙合面上粘结的舌侧扣,控制力值在2.5～3.0 N,拉第二磨牙向远中直至完全竖直;B组采用下颌第一磨牙带环焊双曲或三曲推簧的方法,将推簧放置于下颌第二磨牙牙合面粘结的舌侧扣的近中,推第二磨牙向远中直至完全竖直,力值与A组相同。对2种方法矫治时间的差别及矫治结束后第二磨牙近中牙槽嵴的改建情况进行比较分析。 结果 A组8颗前倾阻生的下颌第二磨牙完全直立所需的矫治时间为4.5～8.4个月,平均6.3个月,B组为6.5～11.5个月,平均8.5个月,2组数据比较P<0.01,有统计学意义;A组下颌第二磨牙完全直立后近中牙槽嵴高度增加的平均值为4.8 mm,B组为5.0 mm,2组比较P＞0.5。 结论 2种矫治方法都成功地竖直了前倾阻生的下颌第二磨牙,并且使第二磨牙的近中牙槽嵴高度增加,A组的方法矫治时间更短。     

正畸治疗中磨牙的拔除和保留(五)悬吊竖直法矫治下颌磨牙阻生

目的：探讨下颌磨牙低位近中、水平阻生的矫治方法和效果。方法：采用直丝弓矫治器,在阻生磨牙近中相邻磨牙带环上焊接悬吊竖直簧,对14例下颌第三磨牙,6例下颌第二磨牙共30个阻生磨牙（其中水平阻生12个、近中阻生18个）进行牵引竖直。结果：阻生磨牙均被快速竖直,排齐整平后纳入治疗系统。竖直磨牙时间1～5个月,平均3个月。X线片显示阻生磨牙周围牙槽骨生长、恢复良好。结论：悬吊竖直法能高效、快速、简便地竖直低位阻生磨牙,并具有同期矫治（不延长矫治期）,有效增强支抗和竖直支抗磨牙的优点。     

自制推簧远中直立近中阻生磨牙的力学分析及临床应用

本文将结合1例上颌第一、第二磨牙近中阻生病例,介绍一种椅旁自制的螺旋推簧,用于近中阻生磨牙的远中直立移动,并探讨该螺旋推簧的力学原理及临床应用,为竖直近中阻生的磨牙提供一种新的治疗方法.     

活动支架竖直近中阻生下颌第二磨牙的临床应用

目的 评价自制活动支架竖直近中阻生下颌第二磨牙的疗效.方法 选择6例下颌第二磨牙近中阻生的安氏Ⅰ类错（牙合）,采用自制活动支架和双颊面管带环,将支架两末端插入第一磨牙带环颊舌面的颊面管内,橡皮链连接支架与阻生磨牙牙面舌侧扣,牵引并竖直磨牙.结果 6例近中阻生磨牙直立,取得良好咬合关系,竖直时间为3～8个月.结论 自制活动支架竖直近中阻生磨牙,疗效明显.     

正畸治疗前倾阻生的下颌第三磨牙的根吸收风险研究

目的：探讨矫治前倾阻生下颌第三磨牙后牙根的改变和根吸收的影响因素,为临床医师提供风险预测的依据。方法：样本共10例（女性8名,男性2名,年龄15～32岁）,下颌第一恒磨牙已拔除或无保留价值,且伴同侧下颌第三磨牙前倾至水平阻生。矫治采用直丝弓矫治器,利用口内辅弓法后推下颌第三磨牙,再通过竖直簧直立第三磨牙。直立前、后拍摄全口曲面断层片进行测量。采用两相关样本非参数检验（Wilcoxon Signed Ranks Test）对矫治前后牙根长度的改变进行对比分析。结果：经过治疗,10例病例都取得满意的疗效。矫治后成人组阻生磨牙根长度有所减少,但未见统计学差异。青少年组牙根长度增加,差异具有显著性（P〈0.05）。结论：通过正畸手段直立阻生磨牙具有可行性和可靠性,为科学的权衡各种治疗方法提供帮助,为患者提供安全、有效的治疗方案。     

拔除下颌第三磨牙后相邻第二磨牙远中牙周情况的早期变化

目的 :观察低位近中阻生的下颌第三磨牙拔除后,相邻第二磨牙远中牙周情况的变化。方法:58例低位阻生的下颌第三磨牙拔除前后随访观察6个月,通过全景片测量相邻第二磨牙远中牙槽嵴高度,临床检查牙周袋深度、龈缘位置和附着水平等牙周指标。结果:58例低位近中阻生的下颌第三磨牙拔除后,相邻第二磨牙远中齿槽嵴高度和龈缘位置均有不同程度的增高,差异有统计学意义。结论:对于年轻患者,应尽早拔除阻生的下颌第三磨牙,有益于增加拔牙后相邻第二磨牙远中牙槽骨的高度。     

下颌智齿阻生类型及其邻牙远中邻面患龋情况的对称性初探

目的 调查下颌第三磨牙生长情况的对称性及其对相邻第二磨牙远中邻面龋患病情况的影响,为临床早期预防性拔除下颌智齿提供依据。方法 纳入2019年11月1日至2019年11月23日在上海交通大学医学院附属仁济医院口腔科拍摄的全景片196张,调查其双侧下颌第三磨牙的对称性,通过卡方检验分析不同阻生类型的下颌第三磨牙与相邻第二磨牙远中邻面龋患病情况之间的关系。结果 双侧下颌第三磨牙对称者187例,占比95.41%。Winter分类中垂直阻生对称性（79.2%）显著高于近中阻生（47.6%）与水平阻生（59.1%）（P=0.001）; Winter分类为近中阻生（46.4%）和水平阻生（38.4%）的下颌第三磨牙,其相邻第二磨牙远中邻面龋发生率显著高于垂直阻生（23.6%）（P=0.001）。结论 下颌智齿具有对称性;为预防相邻第二磨牙远中邻面龋,近中阻生及水平阻生的下颌第三磨牙应在临床上早期预防性拔除。     

应用阻生磨牙竖直器矫正下颌第三磨牙近中倾斜阻生

目的 通过临床应用阻生磨牙竖直器配合使用阻生磨牙直立牙挺辅助矫治近中倾斜阻生的下颌第三磨牙,检验其疗效.方法 选择9名下颌第三磨牙近中倾斜阻生患者使用阻生磨牙竖直器配合使用阻生磨牙直立牙挺进行正畸治疗,共有15颗下颌阻生齿需要治疗.测量矫治前后的曲面断层片下颌第二磨牙和第三磨牙的倾斜角,对比分析矫治前后倾斜角度变化,进行配对t检验.分别测量治疗前后下颌第二磨牙长轴与下颌升支后缘切线、双侧乙状切迹最下缘连线及双侧突顶点连线交角,独立样本t检验表明,矫治前后角度变化无统计学意义(P＞0.1).结果 全部患者矫治效果良好,近中倾斜阻生的第三磨牙实现直立.第二、三磨牙的夹角倾斜度平均减少(55.47±22.07)°,具有显著的统计学意义(P＜0.05).第二磨牙治疗前后倾斜度改变无统计学意义(P＞0.1).结论 阻生磨牙竖直器配合使用阻生磨牙直立牙挺是一种竖直近中倾斜阻生磨牙的简单高效的方法.     

Eruption of third permanent molars after the extraction of second permanent molars. Part 1: Assessment of third molar position and size.

The eruptive path of third molars after extraction of second molars was examined in 63 patients. Panoramic radiographs from the start and the end of active treatment and 3 or more years after treatment were assessed. Study models were used to compare the size of the second and third molars and to assess the final position of the third molars. All third molars erupted; none became impacted. During eruption, maxillary third molar crowns uprighted and maintained their angulation as they came into occlusion. Mandibular third molar crowns continued to upright significantly mesiodistally after active treatment, with space closure the result of horizontal translation rather than mesial tipping. Further uprighting occurred once occlusion was established, although few became as upright as the second molars they replaced. However, mandibular third molar roots were frequently curved distally, thus the third molar crown position was invariably better than the overall tooth angulation would suggest, by 16.5 degrees on average. Model analysis (Richardsons' scoring system) showed 96% of mandibular and 99% of maxillary third molars erupted into a good or acceptable position. Limitations of this scoring system are discussed. The mesiodistal size of third molars was suitable to replace second molars; on average, mandibular third molars were 0.55 mm larger and maxillary third molars were 0.7 mm smaller than second molars.     

Orthodontic uprighting of impacted mandibular permanent second molar: a case report

The mandibular second molars can become impacted beneath the crown of the first molars due to various causes and fail to erupt normally. Presented herewith is a case report of orthodontic uprighting of a mesioangular impacted mandibular right permanent second molar. Though various treatment options were available, an uprighting push spring appliance was used as it is easy to fabricate and produces distal tipping and uprighting of the impacted tooth without the necessity of surgical assistance, bone removal, or splinting. The uprighting of the mandibular second molar was achieved within two months.     

微螺钉直接支抗直立下颌第二磨牙的临床研究

目的 评价微螺钉直接支持的片段弓矫治器直立下颌第二磨牙的效果.方法 本研究包括18例种植修复前正畸患者,平均年龄32.8±5.7岁.样本人群总计有25颗下颌第二磨牙近中倾斜,需要正畸直立治疗.所有患者经牙周专科医师检查不存在活动期牙周病.18例患者在其下颌前磨牙区植入一颗微螺钉(1.6×9.0mm,慈北医疗器械有限公司),植入高度在膜龈结合部位或稍偏向方.愈合一周后,微螺钉头部连接由0.016×0.022英寸(1英寸=25.4 mm)的TMA丝制作的磨牙直立片段弓丝.下颌第二磨牙远中直立治疗前后分别拍摄头颅侧位定位片,并进行头影测量的分析比较.结果 18例患者的25颗近中倾斜的下颌第二磨牙均获得良好的正畸直立治疗效果,直立治疗的平均时间为4.0±1.0个月.相对于下颌平面,第二前磨牙的角度和高度均未发生变化.而第二磨牙角度平均增加16.5度(P＜0.001),第二磨牙和第二前磨牙距离平均增加4.4 mm(P＜0.001),均有显著性意义.第二磨牙远中颊尖高度未发生显著性变化.结论 应用微螺钉直接支抗支持的TMA丝片段弓矫治器可以有效地远中直立下颌倾斜磨牙,支抗稳定,第一磨牙间隙适度扩大.     

改良舌弓矫治下颌第二磨牙近中倾斜的临床应用

目的 评价改良舌弓矫治下颌近中倾斜第二磨牙的疗效。 方法 选择5例下颌第二磨牙近中倾斜病例,采用改良舌弓远中牵引、直立近中倾斜的第二磨牙,观察其临床效果,通过曲面断层片测量评价其疗效。 结果 5例近中倾斜磨牙均远中直立,建立了良好咬合关系,平均疗程5个月。 结论 改良舌弓能有效直立近中倾斜的第二磨牙。     

Vertical eruption patterns of impacted mandibular third molars after the mesialization of second molars using miniscrews

Objective:To investigate (1) whether vertical eruption of impacted third molars improves after mesialization of second molars and (2) what factors affect the vertical eruption of impacted third molars when space caused by missing molars is successfully closed by mesialization of the second molar using miniscrews.Materials and Methods:The treatment group (Group 1) included 52 patients who had (1) missing mandibular first molars (ML-6) or missing deciduous mandibular second molars (ML-E), (2) initially impacted mandibular third molars, and (3) successful space closure of the edentulous area with orthodontics. Panoramic radiographs at start of treatment (T1) and at time of space closure (T2) were collected. The control group (Group 2) included 46 nonedentulous patients with impacted mandibular third molars without molar protraction treatment. Panoramic radiographs with similar T1/T2 treatment times were selected. Nine measurements were obtained regarding horizontal available space, vertical eruption, and third molar angulation.Results:Third molars erupted vertically an average of 2.54 mm in Group 1 compared with 0.41 mm in Group 2. Age, gender, Nolla stage, and angle of the third molars did not show significant correlations with the vertical change of the impacted third molars, whereas the depth of third molar impaction and available space showed significant correlations.Conclusions:Impacted mandibular third molars vertically erupt as a result of uprighting with mesialization of the second molar, and vertical eruption is affected by the initial vertical location of impacted third molars and available space.     

Management of unilaterally deep impacted first, second, and third mandibular molars

Simultaneous impactions of first, second, and third permanent molars comprises a very rare clinical situation with diverse therapeutic approaches and is a difficult challenge for dentists. Early diagnosis and treatment of eruption disturbances contributes to optimal outcomes. This article reports the treatment of a teenager with severe impaction of right mandibular first, second, and third molars, which hinders the masticatory function and dental arch integrity. A decision-making process and a simple orthodontic technique are described. To shorten the treatment time and simplify the procedures, the impacted right mandibular third and second molars were orthodontically uprighted with an innovative tip-back cantilever. Subsequently, the deeply impacted right mandibular first molar was extracted with minimal obstacles. The combined surgical-orthodontic approach resolved a challenging clinical problem and eliminated the need for prosthetic or dental implant replacement of the impacted molars. Good occlusion, normal function, and a healthy periodontium of the patient were also achieved.     

磨牙后区微种植体支抗竖直下颌近中阻生第二磨牙的临床应用

目的探讨磨牙后区微种植体应用于下颌近中阻生第二磨牙竖直的正畸治疗方法,评估其效果。方法选择南京医科大学附属口腔医院正畸科2011—2014年门诊下颌第二磨牙近中阻生的患者13例23颗患牙,采用磨牙后区植入微种植体,牵引23颗患牙向远中移动,引导其竖直、萌出。结果 23颗阻生的下颌第二磨牙全部竖直萌出并建立良好的咬合。竖直治疗平均时间为6.5个月。结论磨牙后区微种植体支抗能简单有效地竖直下颌阻生的第二磨牙,并且可以控制磨牙的垂直向高度,避免对相邻牙齿产生不良影响。