这项工作由国际 Align 研究奖励计划（Align Technology Inc.，亚利桑那州坦佩）资助。然而，资金来源没有参与研究和/或文章的准备工作。我们要感谢 Sandra Tai 博士和 Samuel Tam 博士对提供 Invisalign 隐适美案例的慷慨支持，以及 Nikolas Krstic 对统计分析的专业支持。

这项研究获得了不列颠哥伦比亚大学机构审查委员会的伦理批准（编号 H19-00787）。为了保密，研究中使用的所有样本都经过了去标识化程序。此外，在纳入研究之前，适当地获得了所有参与患者的知情同意。
注意：每位参与者都贡献了四个上颌数字模型，其中包括以下内容：
<ol><li>预处理数字模型，使用iTero扫描上颚</li>
	<li>治疗后数字模型，使用iTero扫描上颚</li>
	<li>预处理模型，从计划软件中导出。</li>
	<li>预测模型，从规划软件导出。</li>
</ol>该协议利用了多种软件工具的组合，其中包括 CloudCompare、Meshmixer 和 Rhinoceros。这些软件平台在促进配准过程和能够分割单个牙齿以分析其运动和方向方面发挥了关键作用。值得注意的是，这些软件工具可以与其他开源软件选项一起复制，前提是它们能够实现类似的目标。 图 1 显示了软件序列的工作流程。
1. 准备工作
<ol><li>通过单击“ 工具”>“导出> STL”，从规划软件中获取立体光刻 （STL） 文件的初始和最终（预测）模型。 注意：从计划软件导出的模型仅显示临床牙冠和虚拟牙龈，而没有上颚。</li>
	<li>通过选择扫描件，单击并选择 导出>导出类型（打开外壳）、数据格式（每个拱门的文件 [拱门方向遮挡]））从扫描模型软件 （OrthoCAD） 获取处理前和处理后数字模型作为 STL 文件。 注意：从模型扫描软件导出的模型不仅包括牙列，还包括牙龈和整个上颚。</li>
</ol>2. CloudCompare中治疗前和治疗后数字模型的腭叠加
<ol><li>打开软件，拖放处理前和处理后数字模型的STL文件。</li>
	<li>选择每个模型，然后单击 “编辑”>“颜色”>“设置唯一 ”以更改所选模型的颜色。</li>
	<li>选择后处理数字模型，然后单击 平移/旋转 图标。单击鼠标右键以拖动模型，使其并排。单击 绿色复选标记。</li>
	<li>选择预处理数字模型，然后单击 分段 图标。</li>
	<li>单击腭部上的四个点，然后单击鼠标右键取消选择。单击 “分段”，然后单击 绿色复选标记。对后处理数字模型重复步骤 2.4 至 2.5。</li>
	<li>隐藏 PostTreatModel.remaining 和 PreTreatModel.remaining 模型，然后同时选择 PostTreatModel.part 和 PreTreatModel.part 模型。</li>
	<li>单击 粗略配准 对齐图标（点对拾取），并在中线两侧的上颚上放置至少三个相应的地标，用于治疗前和治疗后的上颚。单击 “对齐”，然后单击 “绿色复选标记”。</li>
	<li>取消隐藏两个模型的网格，并通过复制变换矩阵，单击“编辑”>“应用变换”，然后粘贴变换矩阵来移动未变换的 PostTreatModel.remaining 模型。 注意：转换矩阵输出显示在控制台中。</li>
	<li>隐藏 PostTreatModel.remaining 和 PreTreatModel.remaining 模型，然后选择 PostTreatModel.part 和 PreTreatModel.part 模型。</li>
	<li>单击 “精细配准”（Fine Registration ） 对齐图标，并确保选择 PreTreatModel.part 模型作为参照。单击 “确定”。 注意：在注册信息窗口中确认生成的均方根 （RMS）。≤ 0.05 RMS 的偏差是可以接受的。</li>
	<li>取消隐藏两个模型的网格，并通过复制变换矩阵，单击“编辑”>“应用变换”，然后粘贴变换矩阵来移动未变换的 PostTreatModel.remaining 模型。</li>
	<li>将叠加的 PostTreatModel.remaining 和 PreTreatModel.remaining 模型另存为 STL 文件。</li>
</ol>3. 使用 Rhinoceros 软件叠加的软件模型准备
<ol><li>分别导入计划软件预处理模型和预测模型的STL文件。 注意：将软件模型导入 Rhinoceros 或 CloudCompare 等测量软件时，将保留方向和模型的配准</li>
	<li>选择模拟牙龈，然后按 Delete 将其删除。</li>
	<li>单击 MeshTools，选择 Meshplane。在牙齿周围画一个平面，并将平面移动到牙冠的咬合 1/3。这将提高叠加精度。</li>
	<li>双击 按钮向右 展开右侧视图。</li>
	<li>输入命令 MeshBooleanSplit 并选择平面和所有齿，然后按 Enter 键。</li>
	<li>删除牙齿的平面和颈部部分，留下 1/3 的咬合牙冠。</li>
	<li>将拆分模型另存为 STL 文件。</li>
	<li>对另一个模型重复所有步骤。</li>
</ol>4. 使用CloudCompare叠加软件预测和后处理数字模型
<ol><li>拖放先前腭叠加的预处理和后处理数字模型的 STL 文件，以及拆分预处理和拆分预测模型。</li>
	<li>选择每个模型，然后单击 “编辑”>“颜色”>“设置唯一 ”以更改所选模型的颜色。</li>
	<li>选择预处理和后处理数字模型，然后单击 平移/旋转 图标。单击鼠标右键以拖动模型，使它们并排。</li>
	<li>请求软件通过取消选中相应的框来隐藏拆分预测模型和后处理数字模型。选择拆分预处理模型和预处理数字模型。</li>
	<li>单击 “粗略配准 ”对齐图标，然后在拆分预处理模型和预处理数字模型的牙冠尖上放置相应的地标。单击 “对齐”，然后单击 “绿色复选标记”。</li>
	<li>通过复制变换矩阵，单击“编辑”>“应用变换”，然后粘贴变换矩阵，取消隐藏拆分预测模型和后处理模型，并移动未变换的后处理模型。</li>
	<li>隐藏 后处理和拆分预测模型。选择预处理和拆分预处理模型。单击 “精细配准 ”对齐图标，可在拆分预处理模型和预处理数字模型之间实现最佳拟合。</li>
	<li>通过复制变换矩阵，单击“编辑”（Edit）>“应用变换”（Apply Transformation），然后粘贴变换矩阵，取消隐藏网格并移动未变换的模型。</li>
	<li>取消隐藏 拆分预测和后处理数字模型，然后 隐藏 拆分预处理模型和预处理数字模型以显示叠加（图 2）。</li>
	<li>将模型另存为 STL 文件。</li>
</ol>5. 使用 Meshmixer 进行冠分割
<ol><li>将拆分预测模型和后处理数字模型导入 Meshmixer。</li>
	<li>单击 “编辑”（Edit） >“复制 ”（Duplicate） 以复制要分割的齿数的模型。在每个型号上贴上相应的要分割的齿号。</li>
	<li>通过单击“眼睛”图标隐藏拆分预测模型，使处理后数字模型保持可见。</li>
	<li>在后处理模型上，单击 “选择 ”（Select） 并调整 画笔的大小。要分割所选牙冠，请在所选牙齿的咬合面上拖动“ 刷牙”工具 ，密切注意牙尖。</li>
	<li>单击 “修改”（Modify） >“反转”（Invert ），然后单击 “编辑”（Edit） >“丢弃”（Discard ） 以删除模型的其余部分，保留分段的表冠。</li>
	<li>通过单击相应的“眼睛”图标，取消隐藏拆分预测模型并隐藏后处理模型。</li>
	<li>对拆分预测模型重复步骤 5.4-5.5。</li>
	<li>将每个选定的表冠导出为 STL 文件。</li>
	<li>对每个牙齿分割重复所有步骤。</li>
</ol>6. 使用 CloudCompare 进行牙科叠加
<ol><li>将分段的治疗后数字牙冠和拆分的软件预测牙冠导入软件。确保方向和云注册保持一致。建立 世界坐标网格 ，规范左右牙的朝向，提高方法的可靠性。网格的中心应表示 CloudCompare 软件云的 （0,0,0,0,0,0,0） 坐标。</li>
	<li>选择两个皇冠，然后单击 编辑 > 法线 > 计算每个顶点>。</li>
	<li>选择每个齿，然后单击 “编辑”>“颜色”>“设置唯一 ”以更改所选型号的颜色。</li>
	<li>通过取消选中该框来隐藏治疗后的牙齿，然后选择隐藏的治疗后牙齿和可见的预测牙齿。</li>
	<li>选择底部视图，单击 “平移/旋转 ”图标，然后使用平面 X、Y 和 Z 旋转牙齿，使颊尖与垂直线对齐。</li>
	<li>选择左侧视图，单击 “平移/旋转 ”图标，然后用水平线对颊尖和舌尖对齐。</li>
	<li>选择后视图，单击 “平移/旋转 ”图标，然后用水平线对颊尖和舌尖。 注意：旨在使其咬合和面部表面与世界轴和平面对齐。确保牙齿的边界框中心位于世界原点。通过遵守世界坐标网格，所有牙齿的位置都将标准化。此步骤可确保所有轴上的 X、Y 和 Z 平移的一致和准确转换，而与单个牙齿的具体位置无关。</li>
	<li>一旦所有尖点对齐，单击“ 平移/旋转 ”图标，在所有视图中将齿居中在网格上。</li>
	<li>取消隐藏治疗后牙齿，选择预测的牙齿和治疗后牙齿。</li>
	<li>单击 “精细配准 对齐”图标，将治疗后的牙齿配准在预测的牙齿上。单击 “确定”。 注意：完成后，CloudCompare 将显示注册信息，包括叠加 RMS（图 3）。</li>
	<li>要确定两颗牙齿之间的位置和旋转差异，请选择治疗后牙齿，复制变形矩阵，单击 “编辑”>“应用变形”，然后粘贴变形矩阵。</li>
	<li>选择“欧拉角”图标以显示预测牙齿和治疗后牙齿之间的旋转和线性运动。</li>
	<li>在电子表格中记录所有平移和旋转测量值。对所有剩余的后牙重复此过程。 注意：使用美国正畸委员会 （ABO） 模型分级系统12 来识别具有临床意义的测量差异。线性差异大于 0.5 毫米，角度差异大于 2 度被认为具有临床相关性。</li>
	<li>在电子表格中调整右侧牙齿前后方向的测量值。这种调整考虑了右侧牙齿到左侧牙齿的标准化方向。</li>
</ol>7.测量规格
<ol><li>了解旋转和测量约定的顺序：CloudCompare 采用 Tait-Bryan ZYX 外在（世界原点）约定进行测量。 注意：对于翻译，轴表示 X（颊舌方向）、Y（近远端方向）和 Z（垂直方向：侵入/挤压）。角运动由 X 轴（Psi - 近远端倾斜）、Y 轴（Theta - 颊舌扭矩）和 Z 轴（Phi - 近远端旋转）22 表示。牙齿运动是根据牙齿的解剖结构来表示的，无论它在牙弓中的位置如何。度量符号 （+， -） 表示从世界原点出发的方向和绕其轴旋转的方向。</li>
	<li>上下文相关性的重要性：请注意，描述牙齿运动的方向性术语（例如，近中、远端、颊舌）指的是特定的牙齿，并不考虑相对于牙弓的改变。</li>
</ol>8. 统计分析
<ol><li>通过 RStudio（版本 1.4.1103）使用 R 统计包（v 3.2.3，RStudio Inc.）进行所有分析。</li>
	<li>随机选择 32 颗牙齿，每隔 1 个月进行重复测量。</li>
	<li>使用两组测量的类内相关系数 （ICC） 和 Bland Altman 分析测试考官内部信度。</li>
	<li>应用 Hotelling 的 T 平方检验来检验角度和线性参数的预测和实现的齿位置之间的平均预测差异。</li>
	<li>使用 P 值的 Bonferroni 校正来调整多个齿比较，目标是 0.05 的家族错误率。</li>
	<li>如果检测到任何显着差异，则进行事后 Hotelling 的 T 平方检验，以确定每种牙齿类型和运动参数的预测差异是否显着。考虑线性测量中 0.25 mm 或更大的差异，以及 2° 或以上的角度测量的临床相关差异。</li>
</ol>

使用数字叠加评估上颌后牙移动

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A prospective clinical study evaluating the efficacy of tooth movement with Invisalign.</a> American Journal of Orthodontics and Dentofacial Orthopedics. 135 (1), 27-35 (2009).</li><li>Simon, M., Keilig, L., Schwarze, J., Jung, B. A., Bourauel, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Treatment+outcome+and+efficacy+of+an+aligner+technique-regarding+incisor+torque,+premolar+and+molar+distalization.">Treatment outcome and efficacy of an aligner technique-regarding incisor torque, premolar and molar distalization.</a> BMC Oral Health. 14, 68 (2014).</li><li>Charalampakis, O., Iliadi, A., Ueno, H., Oliver, D. R., Kim, K. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+of+clear+aligners:+a+retrospective+study+of+patients+who+needed+refinement.">Accuracy of clear aligners: a retrospective study of patients who needed refinement.</a> American Journal of Orthodontics and Dentofacial Orthopedics. 154 (1), 47-54 (2018).</li><li>Gr&#252;nheid, T., Loh, C., Larson, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+accurate+is+Invisalign+in+nonextraction+cases?+Are+predicted+tooth+positions+achieved.">How accurate is Invisalign in nonextraction cases? Are predicted tooth positions achieved.</a> Angle Orthodontist. 87 (6), 809-815 (2017).</li><li>Haouili, N., Kravitz, N. D., Vaid, N. R., Ferguson, D. J., Makki, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Has+Invisalign+improved?+A+prospective+follow-up+study+on+the+efficacy+of+tooth+movement+with+Invisalign.">Has Invisalign improved? A prospective follow-up study on the efficacy of tooth movement with Invisalign.</a> American Journal of Orthodontics and Dentofacial Orthopedics. 158 (3), 420-425 (2020).</li><li>Alwafi, A. A., Hannam, A. G., Yen, E. H., Zou, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+method+assessing+predicted+and+achieved+mandibular+tooth+movement+in+adults+treated+with+clear+aligners+using+CBCT+and+individual+crown+superimposition.">A new method assessing predicted and achieved mandibular tooth movement in adults treated with clear aligners using CBCT and individual crown superimposition.</a> Scientific Reports. 13, 4084 (2023).</li><li>Huanca Ghislanzoni, L. T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+tip+and+torque+on+virtual+study+models:+a+validation+study.">Evaluation of tip and torque on virtual study models: a validation study.</a> Progress in Orthodontics. 26 (1), 14-19 (2013).</li><li>English, W. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Individuality+of+human+palatal+rugae.">Individuality of human palatal rugae.</a> Journal of Forensic Sciences. 33 (3), 718-726 (1988).</li><li>Almeida, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stability+of+the+palatal+rugae+as+landmarks+for+analysis+of+dental+casts.">Stability of the palatal rugae as landmarks for analysis of dental casts.</a> Angle Orthodontist. 65 (1), 43-48 (1995).</li><li>Jang, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+method+for+the+assessment+of+three-dimensional+tooth+movement+during+orthodontic+treatment.">A novel method for the assessment of three-dimensional tooth movement during orthodontic treatment.</a> Angle Orthodontist. 79 (3), 447-453 (2009).</li><li>Chen, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stable+region+for+maxillary+dental+cast+superimposition+in+adults,+studied+with+the+aid+of+stable+miniscrews.">Stable region for maxillary dental cast superimposition in adults, studied with the aid of stable miniscrews.</a> Orthodontics and Craniofacial Research. 14 (2), 70-79 (2011).</li><li>Dai, F. F., Xu, T. M., Shu, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+achieved+and+predicted+tooth+movement+of+maxillary+first+molars+and+central+incisors:+first+premolar+extraction+treatment+with+Invisalign.">Comparison of achieved and predicted tooth movement of maxillary first molars and central incisors: first premolar extraction treatment with Invisalign.</a> Angle Orthodontist. 89 (5), 679-687 (2019).</li><li>An, K., Jang, I., Choi, D. S., Jost-Brinkmann, P. G., Cha, B. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+a+stable+reference+area+for+superimposing+mandibular+digital+models.">Identification of a stable reference area for superimposing mandibular digital models.</a> Journal of Orofacial Orthopedics. 76 (6), 508-519 (2015).</li><li>Miller, R. J., Kuo, E., Choi, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+Align+Technology's+Treat+IIITM+digital+model+superimposition+tool+and+its+case+application.">Validation of Align Technology's Treat IIITM digital model superimposition tool and its case application.</a> Orthodontics and Craniofacial Research. 6 (s1), 143-149 (2003).</li><li>Cevidanes, L. H. C., Oliveira, A. E. F., Grauer, D., Styner, M., Proffit, W. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+application+of+3D+Imaging+for+assessment+of+treatment+outcomes.">Clinical application of 3D Imaging for assessment of treatment outcomes.</a> Seminars in Orthodontics. 17 (1), 72-80 (2011).</li><li>Tait-Bryan angles - Wikimedia Commons. Available from: <a target="_blank" href="https://commons.wikimedia.org/wiki/Tait-Bryan_angles">https://commons.wikimedia.org/wiki/Tait-Bryan_angles</a> (2023)</li><li>Al-Nadawi, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+clear+aligner+wear+protocol+on+the+efficacy+of+tooth+movement.">Effect of clear aligner wear protocol on the efficacy of tooth movement.</a> Angle Orthodontist. 91 (2), 157-163 (2021).</li><li>Cortona, A., Rossini, G., Parrini, S., Dergibus, A., Castroflorio, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clear+aligner+orthodontic+therapy+of+rotated+mandibular+round-shaped+teeth:+A+finite+element+study.">Clear aligner orthodontic therapy of rotated mandibular round-shaped teeth: A finite element study.</a> Angle Orthodontist. 90 (2), 247-254 (2020).</li><li>Nucera, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+composite+attachments+on+orthodontic+clear+aligners+therapy:+A+systematic+review.">Effects of composite attachments on orthodontic clear aligners therapy: A systematic review.</a> Materials. 15 (2), 533 (2022).</li></ol>

作者没有什么可透露的。

腭腭在青春期具有独特的结构;它们在生长过程中保持不变，是个人识别的真实标记，被认为是上颌模型叠加的稳定解剖学参考 24,25,26,27。Dai 等人使用这种方法比较了第一前磨牙拔除后上颌第一磨牙和中切牙与透明矫正器的实现和预测的牙齿运动28。通过Rapidform软件将实现的后处理模...

1999 年，Align（Align Technology Inc.，亚利桑那州坦佩市）将数字制造的可移动正畸矫治器推向市场。最初，该系统旨在解决轻度至中度拥挤或封闭小空间的非生长情况，作为传统固定边缘设备的美学替代方案。随着数十年来在计算机辅助设计和制造 （CAD/CAM）、牙科材料和治疗计划方面的改进，透明矫正器疗法 （CAT） 已被用于治疗全球超过 1000 万名各种咬合不正患者1。最近的一项回顾性研究表明，对于患有轻度咬合不正的青少年人群，CAT 与固定矫治器治疗一样有效，在牙齿排列、咬合关系和过度喷射2 方面的结果显着改善。对于透明矫正器治疗患者来说，预约次数、急诊就诊次数和总体治疗时间也有更好的结果。尽管 CAT 可用于治疗非生长患者的非拔牙、轻度至中度错颌畸形 3,4，并缩短治疗持续时间和坐椅时间5，但尚不清楚该治疗是否与传统唇托的金标准一样有效 4,6,7,8,9，特别是对于前后和垂直矫正 10。
ClinCheck 是 Align 开发的软件平台，旨在为临床医生提供前瞻性牙齿运动的虚拟三维 （3D） 模拟。它主要关注患者的初始状态和临床医生的处方治疗计划，也可以成为患者的视觉交流工具。预测结果与已实现结果之间的任何不匹配都可能需要中途纠正、改进或转换为固定矫治器治疗。因此，软件预测的可靠性引起了研究人员的日益关注。自 2005 年 Lagravere 和 Flores-Mir 发表的系统评价以来 11，对预测模型和治疗后模型之间一致性的研究已经以不同的方式进行了测量，测量方法包括弓长、尖牙间距离、覆合、覆射、中线偏差12、美国正畸委员会客观分级系统 （ABO-OGS） 减少评分13、上下齿间宽度14，以及从锥形束计算机断层扫描15 得出的测量值。
还通过叠加 3D 模型16、17、18、19、20、21 进行了比较。例如，许多当前的软件平台，如ToothMeasure（由Align Technology开发的内部软件），可以使用用户选择的参考点在未经治疗的牙齿、腭部或种植牙上可重复地叠加两个数字模型。由于预测和实现的模型通常不包括腭表面，因此许多先前的研究 15,16,17,18 使用未经处理的后牙作为叠加的参考，包括由于这些牙齿的相对运动而增加误差的可能性。这些研究仅限于足弓的前部区域，在相对简单的病例中，有间距或轻度至中度拥挤。
Grünheid 等人使用数学叠加来量化虚拟治疗计划与实际治疗结果之间的差异，以评估数字模型中没有稳定解剖结构的全牙列 CAT的准确性 20。Haouili 等人在 Compare 软件中的最佳拟合算法中使用了相同的方法，对 CAT21 的牙齿移动功效进行了前瞻性后续研究。其目的是提供有关新兴技术（即 SmartForce、SmartTrack 对准器材料和数字扫描）相关精度的最新信息。他们的发现将整体准确性从 41%17 提高到 50%21 令人鼓舞，但并不否定使用透明矫正器系统仍然无法令人满意地实现某些牙齿运动的可能性。
当预测和实现时，数字模型包括独立于牙列的常见 3D 参考，例如腭褶皱、种植牙或 tori;它们可以在许多合适的软件平台的坐标系内共同配准。如果然后从一颗牙齿中分割出一颗感兴趣的牙齿，并通过数学方法进行转换以匹配其在另一颗牙齿中的位移版本，则转换矩阵包含描述整个 3D 转位所需的完整信息。其内容可以表示为正式约定所描述的三种翻译和三种轮换。在 Invisalign ClinCheck Pro 3D 控制软件上可以找到一个示例，其中指示将牙齿移动到其预测位置所需的 3D 牙齿运动的数值参数显示在牙齿移动表中。
虽然来自规划软件的初始和最终（预测）模型共享由同一软件平台提供的公共坐标系，但它们没有上颚限制了与任何其他数字牙列模型共同配准的可能性，除非它们具有相同的牙列。在这种情况下，假设软件预测和后处理（实现）模型的叠加是可行的。这种可行性源于两对的可用性：初始模型和最终模型（在从规划软件导出过程中自动叠加）以及另一对预处理和实现模型（使用腭部叠加）。可以使用预处理牙列作为参考来注册这些对，以将它们与 Invisalign 初始模型对齐。随后，可以对单个牙齿进行分割，以评估其位置和方向的差异。该评估涉及在模型之间移位齿，转换矩阵将能够对平移和重新定向进行数值量化。
在该方案中，引入了一种评估 CAT 在解决青少年和成人轻度至中度咬合不正方面的有效性的方法，特别关注上颌后牙。原假设是，在第一批透明矫正器之后，上颌后牙中实现的牙齿位置与规划软件预测的牙齿位置之间没有差异。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>CloudCompare&#160;</td>
			<td>GPL software&#160;</td>
			<td>&#160;Version 2.11</td>
			<td>open-source software (https://www.cloudcompare.net/)</td>
		</tr>
		<tr>
			<td>Meshmixer software&#160;</td>
			<td>Autodesk, Inc.</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Rhinoceros 5.0&#160;</td>
			<td>Robert McNeel &#38; Associates</td>
			<td>Version 5.0</td>
			<td></td>
		</tr>
	</tbody>
</table>

measuring maxillary posterior tooth movement: a model assessment using palatal and dental superimposition

自 1999 年 Align Technology， Inc. 推出 Invisalign 隐适美以来，关于 Invisalign（隐形矫治器）治疗的精确度一直存在疑问和争论，尤其是与使用传统固定矫治器相比。这在涉及前后矫正、纵向矫正和横向矫正的情况下尤为重要，在这些情况下，精确的比较至关重要。为了解决这些问题，本研究引入了一个精心设计的方案，主要强调以数字方式叠加上颌后牙的运动，以促进准确的分析。样本包括 25 名患者，他们已经完成了第一批隐适美（透明）矫正器系列。使用上颚跷板和牙列作为稳定参考，以数字方式叠加四个上颌数字模型（治疗前、治疗后、ClinCheck 初始模型和最终模型）。使用软件组合进行模型叠加和齿分割。然后，变换矩阵表示实现的齿位和预测的齿位之间的差异。临床相关差异的阈值为线性位移的 ±0.25 mm，旋转的阈值为 ±2°。使用 Hotelling 的 T 平方检验和 Bonferroni 校正评估差异。旋转（2.036°±4.217°）和扭矩（-2.913°±3.263°）的平均差异在统计学和临床上均有统计学意义，p值分别为0.023和0.0003。前磨牙的去旋和所有后牙的扭矩控制不太可预测。线性测量的所有平均差异在统计学和临床上都不显著，除了第一磨牙似乎比其预测位置略受侵犯（0.256 mm）。对于轻度至中度咬合不正的非拔牙病例，透明矫正器系统似乎符合其对大多数平移牙齿运动和上颌后牙近中远端倾斜的预测。

In 1999, digitally fabricated removable orthodontic appliances were made commercially available by Align (Align Technology Inc., Tempe, AZ). Originally, this system was designed to solve non-growing cases with mild to moderate crowding or close small spaces as an aesthetic alternative to traditional fixed edgewise appliances. With decades of improvements in computer-aided design and manufacturing (CAD/CAM), dental materials, and treatment planning, clear aligner therapy (CAT) has since been used to treat over 10 million patients with various malocclusions worldwide1. A recent retrospective study suggested that CAT is as effective as fixed appliance therapy for the teenage population with mild malocclusions, with significantly improved results in tooth alignment, occlusal relations, and overjet2. The number of appointments, emergency visits, and overall treatment time also had better outcomes for clear aligner therapy patients. Although CAT can be used to treat non-extraction, mild-to-moderate malocclusions in non-growing patients3,4, and shorten treatment duration and chair time5, it remains unclear whether the treatment is as effective as the gold standard of conventional labial braces4,6,7,8,9, especially for anteroposterior and vertical correction10.
ClinCheck is a software platform developed by Align to provide clinicians with virtual three-dimensional (3D) simulations of prospective tooth movements. Primarily concerned with the patient&#39;s initial status and the clinician&#39;s prescribed treatment plan, it can also be a visual communication tool for the patient. Any mismatch between the predicted and achieved results may require a mid-course correction, refinement, or conversion to fixed appliance therapy. Consequently, the reliability of software predictions has drawn increasing attention from investigators. Since Lagravere and Flores-Mir&#39;s systematic review published in 200511, investigations into the concordance between predicted models and post-treatment models have been measured in different ways, measurement methods including arch-length, inter-canine distance, overbite, overjet, midline deviation12, the American Board of Orthodontics objective grading system (ABO-OGS) reduction score13, upper and lower interdental width14, and measures derived from cone-beam computed tomography15.
Comparisons have also been made by superimposing 3D models16,17,18,19,20,21. For example, many current software platforms, such as ToothMeasure (internal software developed by Align Technology), can reproducibly superimpose two digital models using user-selected reference points on untreated teeth, palatal rugae, or dental implants. Since the predicted and achieved models usually do not include the palatal surfaces, many previous studies15,16,17,18 have used the untreated posterior teeth as references for superimposition, including the possibility of adding errors due to the relative movements of these teeth. These studies have been confined to anterior regions of the arch in relatively simple cases with spacing or mild to moderate crowding.
Gr&#252;nheid et al. used mathematical superimposition to quantify the discrepancies between virtual treatment plans and actual treatment outcomes to evaluate the accuracy of full-dentition CAT without stable anatomic structures in digital models20. Haouili et al. used the same method in a best-fit algorithm within the Compare software to conduct a prospective follow-up study on the efficacy of tooth movement with CAT21. The aim was to provide an update on the accuracy associated with emerging technology, i.e., SmartForce, SmartTrack aligner materials, and digital scans. Their findings of an improved overall accuracy from 41%17 to 50%21&#160;were encouraging but do not negate the possibility that some tooth movements are still not satisfactorily achievable with the clear aligner system.
When predicted and achieved, digital models include a common 3D reference independent of the dentition, such as palatal rugae, dental implants, or tori; they can be co-registered within the coordinate system of many suitable software platforms. If a tooth of interest is then segmented from one and transformed mathematically to match its displaced version in the other, the transformation matrix contains the complete information needed to describe the entire 3D transposition. Its content can be expressed as three translations and three rotations described by a formal convention. An example is found on the Invisalign ClinCheck Pro 3D control software, where the numerical parameters indicating the 3D tooth movements needed to move teeth to their predicted positions are shown in a tooth movement table.
While the initial and final (predicted) models from the planning software share a common coordinate system provided by the same software platform, their absence of palates restricts the possibility of co-registering with any other digital dentition model unless they possess identical dentition. In this context, it was hypothesized that the superimposition of software-predicted and post-treatment (achieved) models would be feasible. This feasibility arises from the availability of two pairs: initial and final (automatically superimposed during export from planning software) and another pair of pre-treatment and achieved models (superimposed using palatal rugae). These pairs could be registered using the pre-treatment dentition as a reference to align them with the Invisalign-initial model. Subsequently, the segmentation of individual teeth could be performed to assess differences in their positions and orientations. This assessment involves transposing teeth between the models, and the transformation matrices would enable a numerical quantification of the translations and re-orientations.
In this protocol, an approach to evaluate the effectiveness of CAT in addressing mild to moderate malocclusions in both adolescents and adults was introduced, specifically focusing on the maxillary posterior teeth. The null hypothesis was that there was no difference between the achieved and the planning software-predicted tooth position in the maxillary posterior teeth after the first series of clear aligners.

作者聚焦：透明矫正器治疗中上颌后牙的 3D 移动评估

测量上颌后牙运动：使用腭和牙齿叠加的模型评估

至少需要 24 个案例样本量来检测平均尖端和扭矩角度的 0.6° 效应变化，功率为 80%，alpha 为 0.0523。纳入标准如下：（1） 通过第一磨牙的全恒牙列，（2） I 类咬合不正，或小于 2 mm 的 II /III 类咬合不正，有间距，或经过非拔牙 Invisalign 治疗的轻度至中度拥挤，（3） 至少完成第一批 Invisalign 隐适美矫正器，以及 （4） 在初始和精细口腔内扫描中都出现腭皱。排除标准是：（1）以...

Watch this Scientific Journal Video about Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition at JoVE.com

这份手稿提出了一个全面的方案，使用数字模型叠加评估上颌后牙的三维 （3D） 运动，使用数字模型叠加，这是正畸学和牙颌面骨科的宝贵工具。

Since the introduction of Invisalign by Align Technology, Inc. in 1999, questions and debates have persisted regarding the precision of Invisalign (clear ...

在评估正畸治疗结果时，牙齿运动评估很重要。我们将演示一种评估上颌后牙在接受透明矫正器治疗时三维运动的方法。该协议提供了多种软件工具的组合，以及腭部和牙列作为稳定的参考。这种组合允许单个牙齿的叠加和分割，以分析它们的运动和方向。该协议展示了一种分析软件预测模型与实际治疗结果之间差异的新方法。通过了解软件预测治疗的疗效和准确性，临床医生将有更好的判断来规划牙齿移动。

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Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition

670 次观看.  King Abdulaziz University. 在评估正畸治疗结果时，牙齿运动评估很重要。我们将演示一种评估上颌后牙在接受透明矫正器治疗时三维运动的方法。该协议提供了多种软件工具的组合，以及腭部和牙列作为稳定的参考。这种组合允许单个牙齿的叠加和分割，以分析它们的运动和方向。该协议展示了一种分析软件预测模型与实际治疗结果之间差异的新方法。通过了解软件预测治疗的疗效和准确性，?...

视频: 作者聚焦：透明矫正器治疗中上颌后牙的 3D 移动评估

Since the introduction of Invisalign by Align Technology, Inc. in 1999, questions and debates have persisted regarding the precision of Invisalign (clear aligner) therapy, particularly when compared to the use of traditional fixed appliances. This becomes particularly significant in cases involving anteroposterior, vertical, and transverse corrections, where precise comparisons are of paramount importance. To address these inquiries, this study introduces a meticulously devised protocol, placing a primary emphasis on digitally superimposing the movement of maxillary posterior teeth to facilitate accurate analysis. The sample included 25 patients who had completed their first series of Invisalign (clear) aligners. Four maxillary digital models (pre-treatment, post-treatment, ClinCheck-initial, and final models) were digitally superimposed using the palate rugae and dentitions as stable references. A software combination was used for model superimposition and tooth segmentation. Transformation matrices then expressed the differences between the achieved and predicted tooth positions. Thresholds for clinically relevant differences were at &plusmn;0.25 mm for linear displacement and &plusmn;2&#176; for rotation. Differences were assessed using Hotelling's T-squared tests with Bonferroni correction. The mean differences in rotation (2.036&#176; &plusmn; 4.217&#176;) and torque (-2.913&#176; &plusmn; 3.263&#176;) were significant statistically and clinically, with p-values of 0.023 and 0.0003 respectively. De-rotation of premolars and torque control for all posterior teeth were less predictable. All mean differences for the linear measurements were statistically and clinically insignificant, except that the first molars seemed slightly (0.256 mm) more intruded than their predicted position. The clear aligner system appears to meet its prediction for most translational tooth movements and mesial-distal tipping in maxillary posterior teeth for non-extraction cases with mild to moderate malocclusions.

This manuscript presents a comprehensive protocol to evaluate the three-dimensional (3D) movement of maxillary posterior teeth with clear aligners using digital model superimposition, an invaluable tool in orthodontics and dentofacial orthopedics.