Vongtiang Natnicha, Tongkitcharoen Nathaset, Eurutairat Sawitt, Manopatanakul Somchai, Santiwong Peerapong, Viwattanatipa Nita
Faculty of Dentistry, Mahidol University, Bangkok, Thailand.
Dental Department, Bueng Kan Hospital, Bangkok, Bueng Kan, Thailand.
Orthod Craniofac Res. 2025 Apr;28(2):400-411. doi: 10.1111/ocr.12889. Epub 2024 Dec 28.
To investigate maxillary canine movement accuracy and anchorage during space closure in first premolar extraction cases (maximum anchorage) using In-House Clear Aligners (IHCAs).
A randomised controlled trial with a split-mouth design recruited 16 adults in university setting. Each patient was randomly assigned by side for canine retraction using 12 IHCAs to both the experimental palatal power arm (Pa) and non-Pa control (C). Accuracy was assessed using GOM Inspect by superimposing the virtual and actual digital models between pretreatment and 12th IHCA. Paired t-test or Wilcoxon signed-rank test was used to compare virtual-power arm (VPa) versus actual-power arm (APa) and virtual-control (VC) versus actual-control (AC). Root mean square error (RMSE) was calculated.
Pa displayed a significant difference in preliminary canine distalisation (VPa 2.0 mm vs. APa 2.4 mm), while the control did not differ. Both Pa and control exhibited significantly greater actual distal crown tipping than virtual movement (VPa 4.4° vs. APa -6.3°/VC 4.4° vs. AC -4.3°). AC achieved more canine rotation than VC. RMSE was slightly greater in Pa than control for canine distalisation (Pa 0.6 vs. C 0.55 mm) and distal crown tipping (Pa 10.9° vs. C 8.99°). Conversely, Pa displayed better accuracy in canine rotation. For anchorage, Pa and control exhibited significantly greater actual mesialisation and mesial tipping than virtual. RMSE for anchorage mesialisation and mesial tipping were comparable between Pa and control.
Preliminary canine retraction using Pa may result in greater error in distal crown tipping but less rotation than control.
ISRCTN 14020146 by the International Standard Randomised Controlled Trial Registry.
使用自制透明矫治器（IHCA）研究拔除第一前磨牙病例（最大支抗）关闭间隙过程中上颌尖牙的移动准确性和支抗情况。
一项采用分口设计的随机对照试验在大学环境中招募了16名成年人。每位患者通过随机分组，一侧使用12副IHCA进行尖牙后移，分别应用于实验性腭部加力臂（Pa）和非加力臂对照（C）。使用GOM Inspect软件通过叠加治疗前和第12副IHCA时的虚拟和实际数字模型来评估准确性。采用配对t检验或Wilcoxon符号秩检验比较虚拟加力臂（VPa）与实际加力臂（APa）以及虚拟对照（VC）与实际对照（AC）。计算均方根误差（RMSE）。
Pa在尖牙初步远中移动方面显示出显著差异（VPa 2.0毫米对APa 2.4毫米），而对照组无差异。Pa组和对照组实际远中冠倾斜均显著大于虚拟移动（VPa 4.4°对APa -6.3°/VC 4.4°对AC -4.3°）。AC组比VC组实现了更多的尖牙旋转。在尖牙远中移动（Pa 0.6对C 0.55毫米）和远中冠倾斜（Pa 10.9°对C 8.99°）方面，Pa组的RMSE略大于对照组。相反，Pa组在尖牙旋转方面显示出更好的准确性。对于支抗，Pa组和对照组实际近中移动和近中倾斜均显著大于虚拟移动。Pa组和对照组在支抗近中移动和近中倾斜的RMSE相当。
使用Pa进行尖牙初步后移可能导致远中冠倾斜的误差更大，但旋转比对照组小。
国际标准随机对照试验注册库的ISRCTN 14020146。
