无托槽隐形矫治器设计平面导板对上牙列牙齿移动的影响

目的 探讨无托槽隐形矫治器设计平面导板,对上中切牙压低效率的影响及支抗前磨牙、磨牙的变化,以期对无托槽隐形矫治器设计平面导板矫治深覆(牙合)提供参考.方法 分别选取无托槽隐形矫治器设计平面导板和无平面导板矫治深覆(牙合)的病例各6例,两组均设计上中切牙不少于0.7mm的压低,通过前牙压低矫正深覆(牙合).前磨牙及磨牙作为支抗牙不设计移动.以腭穹窿为参照,重叠设计压低前后的数字化模型,比较两组上颌中切牙压低效率的差异,以及两组支抗前磨牙和磨牙的差异.结果 平面导板组上中切牙压低效率为33％,无平面导板组上中切牙压低效率为8％,二者的差异无统计学意义(P＞0.05);平面导板组第一前磨牙、第二前磨牙、第一磨牙和第二磨牙分别伸长0.3、0.1、0.2和0.1mm;无平面导板组第一前磨牙、第二前磨牙、第一磨牙和第二磨牙分别压低0.0、0.2、0.1和0.1mm,两组的差异均有统计学意义(P＜0.05);平面导板组和无平面导板组未设计移动的第一磨牙分别颊倾0.0mm和0.3mm,二者的差异有统计学意义(P＜0.05).结论 无托槽隐形矫治器设计平面导板对上颌中切牙的压低无明显影响,但能有效伸长支抗前磨牙及磨牙,克服无托槽隐形矫治器"(牙合)垫效应"造成的后牙压低,并维持磨牙水平向的位置,对深覆(牙合)的矫正发挥一定作用.     

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。     

无托槽隐形矫治器远移上颌磨牙的疗效评价

目的:评价无托槽隐形矫治器远中移动上颌磨牙的疗效.方法:选取安氏Ⅱ类错(牙合)患者15例,平均年龄为25.3岁.应用无托槽隐形矫治器远中移动上颌磨牙,通过重叠磨牙远移前后的三维数字化模型,并进行三维测量分析评价其远中移动磨牙的疗效.结果:双侧第一磨牙均平均向远中移动2.58 mm,左右侧第二磨牙分别平均向远中移动2.57 mm和2.68 mm,双侧中切牙均平均向近中移动0.34 mm.双侧中切牙在水平向上无明显移动,左右侧第一磨牙均平均颊向移动0.96 mm和0.97mm,左右侧第二磨牙平均颊向移动1.01 mm和1.11 mm.双侧中切牙无明显伸长或压低,双侧第一磨牙均平均压低0.26 mm,左右侧第二磨牙分别平均压低0.37 mm和0.36 mm.双侧第一磨牙和第二磨牙均无明显颊腭向旋转.结论:无托槽隐形矫治器能有效地远中移动上颌磨牙,但会引起轻微的磨牙压低和前牙支抗丧失.     

活动翼托槽与直丝弓矫治器矫治安氏Ⅱ类1分类错临床疗效比较

目的探讨活动翼托槽矫治器与直丝弓矫治器矫治安氏Ⅱ类1分类错患者临床疗效的差异。方法选择25例患者,随机分成2组,分别采用以上2种矫治器进行矫治,对2组各治疗阶段所需时间以及治疗前后牙颌组织头影测量数据进行比较分析。结果与直丝弓矫治器组相比,活动翼托槽组在排齐、整平牙列和关闭间隙阶段所用时间明显减少,而在精细调节阶段时间增加,差异有统计学意义（P〈0.05）;磨牙前移量减少,上下前牙更为直立,差异有统计学意义（P〈0.05）;两组颌骨关系变化差异无统计学意义（P〉0.05）。结论与传统直丝弓矫治器相比,活动翼托槽矫治器可以缩短整体治疗时间,但其对前牙转矩的控制及牙列的精细调节不足。     

尖牙垂直矩形附件位置及尺寸对隐形矫治器脱位力的影响

目的探讨尖牙上垂直矩形附件的位置及尺寸对无托槽隐形矫治器的垂直向及水平向脱位力的影响, 以期为临床应用提供参考。方法本研究为实验研究, 利用3D打印技术建立测试尖牙脱位力模型, 将矫治器附件分成3 mm龈端组、3 mm切端组、5 mm龈端组及5 mm切端组, 测试不同附件的垂直向及水平向的最大脱位力值, 每组重复14次。结果垂直向脱位力测试显示:3 mm龈端组、3 mm切端组、5 mm龈端组和5 mm切端组的垂直向脱位力分别为(7.10±1.98) N、(7.39±0.41) N、(6.22±1.35) N和(6.38±0.70) N, 其中3 mm切端组与5 mm切端组间差异有统计学意义(P=0.001);水平向脱位力测试结果显示:3 mm龈端组、3 mm切端组、5 mm龈端组和5 mm切端组的水平向脱位力分别为(3.40±0.34) N、(2.40±0.23) N、(3.85±0.24) N和(2.11±0.21) N, 各组间均存在统计学意义差异(P<0.01)。结论尖牙切端设计垂直矩形附件时, 3 mm附件的垂直向脱位力反而大于5 mm附件, 在尖牙的龈端设计附件其所获得...     

无托槽隐形矫治矩形附件对上颌磨牙远中移动力学影响的三维有限元分析

目的:建立无托槽隐形矫治远移上颌第二磨牙的三维有限元模型,计算牙周膜应力分布及第二磨牙位移趋势,为无托槽隐形矫治器远中移动上颌第二磨牙位移量、附件设计提供理论依据.方法:通过CT扫描获得患者上颌骨DICOM文件,采用Mimics、Geomagic Studio等软件分别建立无附件上颌第二磨牙远中移动0.2 mm(模型A...     

牙齿几何外形和模型底座厚度对隐形矫治器厚度的影响

目的研究牙齿几何外形和模型底座厚度对热成型隐形矫治器厚度的影响。方法层析扫描标准上颌模型,形成数字图像,通过数字化三维图像处理,激光快速成型输出底座厚度分别为0、1、2、3、4、5、6、7、8、9、10 mm的树脂模型共11副,在每个树脂模型上通过热压膜成型制作10副矫治器,标记每副矫治器上14个牙位的唇颊面和舌腭面牙冠面轴点,使用千分尺测量牙冠面轴点处矫治器的膜片厚度,比较热压膜成型后不同牙位上隐形矫治器的厚度,分析厚度分布规律。结果底座厚度为0 mm时,隐形矫治器中切牙到第二磨牙唇颊面厚度从0.398 mm均匀递增到0.504 mm,坐标图表现为均匀递增的直线,膜片厚度随牙位变化的直线公式为y=0.019x+0.379,拟合度和相关性良好。尖牙腭面膜片厚度最大,第一磨牙腭面膜片厚度大于第二前磨牙,表现为S形曲线。不同底座厚度的树脂模型上热成型的矫治器唇颊面和舌腭面膜片厚度随牙位变化的规律基本相同。隐形矫治器唇颊面和舌腭面的膜片厚度随模型底座厚度的增加呈递减趋势。结论隐形矫治器唇颊面厚度从前牙到后牙均匀递增;矫治器腭面厚度以尖牙最厚,分布无明显规律。模型底座厚度对隐形矫治器厚度有影响。     

无托槽隐形矫治器不同设计对伴牙槽骨吸收中切牙压低效能的有限元分析

目的:在三维有限元模型中,比较不同包裹面积及不同步距设计的无托槽隐形矫治器,对伴有不同程度牙槽骨吸收的右上中切牙压低效能的影响。方法:建立含3种包裹面积(100%、75%、50%)、3种步距设计(0.1 mm, 0.15 mm, 0.2 mm)的无托槽隐形矫治器三维有限元模型,模拟3种牙槽骨水平吸收状态下(牙槽骨正常水平、水平吸收1/3、水平吸收1/2),压低右上中切牙时,其位移及牙周膜应力的变化。结果:除牙槽骨水平吸收1/2、包裹面积50%、步距0.1 mm组外,各组右上中切牙主要表现为：在垂直向上近中切角伸长,其余部分压低,近中切角伸长量小于根尖压低量;在唇舌向上牙冠及牙根舌向移动,近中切角及切缘位移量大于根尖。另外,随着矫治器步距的增大,右上中切牙位移量也随之增大。各组右上中切牙牙周膜总体应力分布较均匀,腭侧面应力值大于唇侧面,应力值随矫治器步距增加而增加。矫治器步距设置为0.1 mm时,除包裹面积为50%的矫治器组产生的矫治力小于150 g/cm²,其余组矫治力均介于150～260 g/cm²之间;矫治器步距设置为0.15 mm和0....     

3种无托槽隐形矫治器附件粘接方法的比较研究

目的 比较全酸蚀粘接剂、自酸蚀粘接剂和树脂加强型玻璃离子水门汀3种材料粘接无托槽隐形矫治器附件的操作时间和临床效果。方法 将采用无托槽隐形矫治器矫治的30例错牙合畸形患者（附件156个）随机分为3组,每组10例。A组采用3M Adper Single Bond 2全酸蚀粘接剂和3M Z350纳米充填树脂粘接附件,B组采用3M Adper Easy One自酸蚀粘接剂和3M Z350纳米充填树脂粘接附件,C组直接采用GC Fuji Ortho LC树脂加强型玻璃离子水门汀粘接附件。记录每个附件的操作时间,评价粘接时、治疗1个月和6个月时3组附件的失败情况。结果 C组附件的操作时间较A、B组短（P<0.01）。3组附件之间的粘接失败率无统计学差异（P>0.05）,同一组内不同时间的粘接失败率也无统计学差异（P>0.05）。结论 3种材料粘接附件的稳定性均能达到满意的效果,但树脂加强型玻璃离子水门汀操作简便,更适宜临床推广。     

卡环固位力的循环测试与分析

目的　观察卡环在反复脱位循环过程中固位力的变化趋势 ,探讨卡环设计时适宜倒凹的选择依据 ,为义齿卡环设计获得最佳临床效果提供依据。方法　使用Chatillon测力仪 ,测试临床常用钴铬合金铸造三臂卡。在前磨牙与磨牙的 0 2 5mm、0 5 0mm、0 75mm 3个倒凹深度上 ,卡环在脱位循环中固位力的变化。结果　所得数据经SPSS10 0统计软件做相关及回归分析 ,表明卡环固位力随脱戴次数增加而减小 ,二者存在线性关系 ,且不同基牙、不同倒凹的固位力衰减率之间差异有极显著性 (P <0 0 1)。前磨牙 0 5 0mm倒凹组卡环经 4 0 0次脱位后 ,其固位力反而开始小于 0 2 5mm倒凹组卡环的固位力 ;0 75mm倒凹组卡环固位力衰减最明显 ,达 0 76 70kg。磨牙组卡环固位力衰减趋势比较相似 ,最终固位力仍以 0 75mm倒凹组者最大 ,0 2 5mm倒凹组卡环固位力最小。结论钴铬合金铸造前磨牙卡环进入倒凹深度以 0 2 5mm为宜 ;磨牙卡环弹性较大 ,因此卡环进入倒凹的深度可较前磨牙更深。     

舌向整体移位设计量对隐形矫治力影响的研究

目的 利用传感器芯片对不同移位设计量的隐形矫治器所产生的矫治力进行测量,探讨移位设计量对隐形矫治力及其衰减的影响,为临床正畸矫治设计提供参考.方法 选用厚度1.0mm的热压膜材料（Erkodent,德国）压制右上中切牙舌向移位设计量分别为0.2、0.3、0.4、0.5和0.6mm的隐形矫治器,利用隐形矫治微型测力系统测量矫治器产生的矫治力并观察其在2周内的衰减情况.结果 移位设计量为0.2、0.3、0.4、0.5、0.6mm的矫治器所产生的矫治力的平均值分别为8.047、9.250、10.189、11.821、12.247N.在矫治器戴入的最初8h矫治力衰减迅速,之后衰减缓慢直至第4天起矫治力维持在较为平稳的水平.结论 随矫治器移位设计量的增加,隐形矫治器产生的矫治力也相应增加.推荐上中切牙舌向整体移动的移位量设计不应超过0.5mm.患者在佩戴每副矫治器的最初4天应尽量全天佩戴.     

固定矫治器与隐形矫治器对正畸治疗疼痛影响差异的Meta分析

目的    比较在正畸治疗过程中固定矫治器与隐形矫治器对患者疼痛影响的差异。方法    计算机检索Cochrane Library、PubMed、中国知网等数据库,查找使用固定矫治器与隐形矫治器进行正畸治疗的相关文章。通过Meta分析比较在正畸治疗过程中两种矫治器对患者疼痛影响的差异。结果    共纳入11篇相关文献,其中7篇为随机对照试验（RCT）研究,4篇为对照临床试验（CCT）研究。共计患者683例,其中使用隐形矫治器（研究组）患者348例,使用固定矫治器（对照组）患者335例。Meta分析结果显示,矫治器佩戴后1、3、5、7 d,研究组患者的疼痛程度均小于对照组,差异有统计学意义（均P < 0.05）。结论    矫治器初戴1周内,隐形矫治器对患者产生的疼痛程度小于固定矫治器。临床上应用隐形矫治器可能会提高患者依从性与配合度。     

The impact of personality on adult patients' adjustability to orthodontic appliances

Objective:To evaluate the impact of psychological traits on patients'' choice of orthodontic appliances and their adjustability to orthodontic treatment.Materials and Methods:The sample consisted of 68 adult patients divided into three groups (28 buccal, 19 lingual, and 21 clear aligners). Prior to treatment participants filled out the Brief Symptom Inventory to assess symptoms of mental distress and the Narcissistic Vulnerability Scale to assess narcissistic personality traits. During the first week after appliance delivery and on day 14, patients completed a Health-Related Quality of Life questionnaire to assess their perception of pain and four areas of dysfunction. The correlation between personality traits and patients'' reaction to treatment was evaluated.Results:Somatization was the only trait that affected the choice of lingual and clear aligner appliance. Reduced self-esteem regulation was associated with increased pain in all patients, while exploitation was associated with pain in lingual patients. Narcissistic vulnerability slightly influenced patients'' adaptability to orthodontic appliances. Although adjustability to lingual appliances was the most difficult, only two parameters were affected by personality features. In the buccal group, adjustability was affected by numerous parameters. Adaptation to the clear aligner appliance was relatively uneventful and least affected by psychological features.Conclusion:Anxious individuals tend to prefer lingual and clear aligner appliances. The selection of lingual and clear aligner appliances governs the patient''s response and recovery process, leaving little room for the effect of psychological features. On the other hand, the buccal appliance allows for greater impact of personality traits on adjustability.     

舌侧矫治器对牙周致病菌的影响

目的研究舌侧矫治器对患者牙周临床指标和牙周致病菌的影响。方法收集成年正畸治疗患者55例资料,28例使用颊侧矫治器作为对照组,27例使用舌侧矫治器作为试验组,于治疗前和治疗6个月后,分别记录菌斑指数、龈沟出血指数、探诊深度,PCR检测龈下菌斑中牙龈卟啉单胞菌(Porphyromonas gingivalis,Pg)、伴放线放线杆菌(Actinobacillus actinomycetemcomtans,Aa)、福赛斯坦氏菌(Tannerella forsythensis,Tf)3种牙周致病菌的检出率。结果治疗6个月试验组菌斑指数、龈沟出血指数、探诊深度分别为2.36±0.71、2.05±0.49、(3.43±0.56)mm,对照组分别为1.86±0.44、1.67±0.25、(2.87±0.74)mm,2组间差异均有统计学意义(P<0.05);试验组Pg、Aa检出率分别为37.0%和22.2%,对照组的Pg、Aa检出率分别为14.3%和10.7%,试验组高于对照组(P<0.05)。结论舌侧矫治器,较颊侧矫治器,对牙周临床指标影响更大,可造成更多的牙周致病菌聚集。     

Biomechanics in lingual orthodontics: What the future holds

The field of orthodontics faced a few fundamental pivots since 1800. Edward Angle introduced a systematic approach to treating patients in 1899. Between 1920 and 2000, development of new orthodontic appliances as well as improvements in orthodontics education reshaped orthodontics. Digital technology has changed how orthodontists treat malocclusions in the last two decades. Specifically, advances in digital orthodontics introduced a paradigm shift in lingual orthodontics attracting more orthodontists especially recently graduated practitioners to offer lingual appliances. This review aimed to point out some of important biomechanical factors in lingual orthodontics and to delineate commonalities and contrasts of these factors in clear aligners and labial systems. Highlights of two work in-progress lingual systems were also discussed. One can reason that better understanding of the advantages and challenges associated with lingual systems especially in comparison to clear aligners and labial systems is essential to creating a fully customized orthodontic experience for patients.     

Lingual retention and the elimination of the visible clasp arm

The modern removable partial denture (RPD), in response to the increased esthetic demands of our patients, is no longer acceptable if it requires visible buccal and facial clasp arms for retention. By eliminating the bracing arm and having its functions taken by paralleled guide planes and precise, positive rests, the retentive element, a lingual circumferential wire clasp arm, will provide the same amount of retentive force as if it were placed on the buccal surface and will not be visible. Designs for the major connector either plate the lingual surface of the abutment or, as in a lingual bar, leave that surface open. Both of these situations are adaptable to the lingual retentive clasp and are illustrated in this article. CLINICAL SIGNIFICANCE: Design features such as metal clasps needed for the retention of RPDs can be very unsightly, creating an esthetic problem. This article reviews the concepts for creating lingual clasp arms that enhance the esthetic quality of prostheses.     

骨埋伏阻生下颌第三磨牙颊舌侧骨壁厚度测量及分类

目的 根据颊舌侧牙槽骨壁厚度差异,将骨埋伏阻生下颌第三磨牙进行分类,为选择去骨方式提供依据。方法 以在我院放射科做过锥形束CT（cone-beam computed tomography, CBCT）的连续病例为对象,筛选110颗重度骨埋伏阻生的下颌第三磨牙作为研究样本。采用3种方法对CBCT图像进行测量,第1种方法为线距测量法,即用CBCT图像分析软件测量牙冠中点、釉牙骨质界中点和牙根中点处的颊舌侧骨壁厚度,以平均颊舌侧骨壁厚度差值作为分类标准（差值的绝对值小于1 mm为中央位,大于1 mm为颊侧位或舌侧位）。第2种方法为目测法,即目测CBCT图像并按颊舌侧骨壁厚度分类。第3种方法为按牙列的位置分为颊侧移位、舌侧移位和正中位。以线距测量法为金标准,比较后2种方法的诊断价值。结果 110颗阻生牙按线距测量法分类,舌侧位96例（87.3%）,中央位13例（11.8%）,颊侧位1例（0.9%）。按目测法分类,舌侧位93例（84.5%）,中央位16例（14.5%）,颊侧位1例（0.9%）。按牙列的位置分类,颊侧移位59例（53.6%）,正中位48例（43.6%）,舌侧移位3例（2.7%）。以线距测量法为金标准,目测法的一致率为88.18%,在判断舌侧位、中央位和颊侧位上的敏感度分别为91.67%、61.54%和100%,特异度分别为64.29%、91.75%和100%,youden指数分别为0.56、0.53和1。牙列分类法的一致率为3.64%,在判断舌侧位、中央位、颊侧位上的敏感度分别为3.13%、0%和100%,特异度分别为100%、50.52%和46.79%,youden指数分别为0.03、0.49和0.53。结论 骨埋伏阻生下颌第三磨牙以舌侧位居多、中央位次之、颊侧位最少。提示骨埋伏阻生牙应以舌侧去骨为主。临床上可用目测法判断颊舌侧位置。按牙列分类与骨壁厚度无关。     

Force changes associated with different intrusion strategies for deep-bite correction by clear aligners

Objectives:To investigate the relationships among different intrusion patterns of clear overlay aligners and the corresponding orthodontic forces and to provide guidance for clinical treatment.Materials and Methods:Five sets of removable thermoplastic-formed aligners with the same thickness, designed for different intrusion procedures (G0 aligners as a control group, with no activation; G1 aligners for intruding canines; G2 aligners for intruding incisors; G3 aligners for intruding canines and incisors with the same activations; G4 aligners for intruding canines and incisors with different activation), were manufactured, and the corresponding intrusion forces were measured with a multiaxis force/torque transducer measurement system in real time.Results:With the same activation (0.2-mm intrusion) and rectangular attachments placed on the premolars and first molars, the canines experienced the largest intrusive force when intruded alone using G1 aligners. The canines received a larger intrusive force than incisors in G3. The incisors received similar forces in G2 and G3. First premolars endured the largest extrusive forces when all anterior teeth were intruded with G3 aligners. Extrusion forces were exerted on canines and lateral incisors when using G4 aligners.Conclusions:Aligners with different intrusion patterns exert different forces on incisors, canines, and premolars, and the forces were closely related to the designed activation, shape and position of the attachment and relative movement of the adjacent teeth.     

A Comparison of the Periodontal Health of Patients during Treatment with the Invisalign® System and with Fixed Lingual Appliances

OBJECTIVE: Evaluation of the periodontal health of patients during treatment with the Invisalign system or fixed lingual appliances. STUDY DESIGN: The study was designed as a concomitant trial of two groups of consecutive patients. The lingual patients were evaluated between February and May 2005. PATIENTS AND METHODS: Thirty patients each with aligners or fixed lingual appliances were examined at three consecutive control visits for their periodontal status. All the Invisalign patients and some of those wearing lingual appliances were patients from the Department of Orthodontics and Dentofacial Orthopedics of the Charité Berlin. The rest were recruited from the practices of two licensed orthodontists. The patients' periodontal health was evaluated in reference to a modified Gingiva, modified Plaque and modified Papillary Bleeding Index; we also measured the sulcus probing depth. All indices were documented buccally in the 1st and 3rd quadrants, and lingually in the 2nd and 4th quadrants from central incisor to first molar. The sulcus probing depth was measured mesially, distally, buccally and lingually in each quadrant's first molar and first premolar. Each control visit was concluded with detailed, individualized instructions in oral hygiene. RESULTS: Overall, the Invisalign patients demonstrated significantly better modified indices. However, the sulcus probing depths were very similar in both treatment groups. CONCLUSION: Although all the teeth and parts of the keratinized gingiva are covered nearly all day during Invisalign treatment, the periodontal risk is lower than that associated with fixed lingual appliances. This may be due to the fact that aligners are removable, permitting unimpeded oral hygiene. In contrast, the lingual tooth surfaces are very difficult to clean when fitted with a fixed appliance.