Kim Kiyean, Choi Youn-Kyung, Kim Sung-Hun, Kim Seong-Sik, Kim Yong-Il
Department of Orthodontics, Dental Research Institute, School of Dentistry, Pusan National University, Geumoro 20, Mulgeumeup, Yangsan, 50612, South Korea.
Dental and Life Science Institute, School of Dentistry, Pusan National University, Yangsan, 50612, South Korea.
Sci Rep. 2025 Jul 1;15(1):22220. doi: 10.1038/s41598-025-07110-6.
Clear aligners have transformed orthodontic treatment; however, they exhibit limited effectiveness in closing extraction spaces due to cumulative movement errors and excessive tipping. This proof-of-concept study introduces an innovative multi-step finite element method (FEM) for simulating sequential clear aligner applications in extraction space closure. A compensation protocol, incorporating an adaptive iterative FEM, was compared with a conventional protocol, and movement precision and unintended tipping were analyzed. The results demonstrated that the compensation protocol significantly reduced tipping (≤ 1°) compared to the conventional approach (> 6°) and minimized the mismatch between crown and root movements. Additionally, the compensation protocol consistently maintained a high achievement rate, preventing the progressive loss of movement efficiency typically observed with conventional protocols. It also provided a more controlled vertical displacement, thereby reducing unwanted extrusion. Furthermore, synchronized crown-root movement contributed to more stable bodily movement, ensuring that teeth followed the intended trajectory more accurately. These findings highlight the potential of the compensation protocol in improving treatment predictability and accuracy in extraction cases. This approach enables systematic adjustment of aligner design based on actual tooth movement, offering an optimized strategy for clear aligner biomechanics and potentially enhancing clinical outcomes in orthodontic treatment.
透明矫治器已经改变了正畸治疗；然而，由于累积的移动误差和过度倾斜，它们在关闭拔牙间隙方面效果有限。这项概念验证研究引入了一种创新的多步有限元方法（FEM），用于模拟在拔牙间隙关闭中连续应用透明矫治器的过程。将一种包含自适应迭代有限元方法的补偿方案与传统方案进行比较，并分析移动精度和意外倾斜情况。结果表明，与传统方法（>6°）相比，补偿方案显著减少了倾斜（≤1°），并使牙冠和牙根移动之间的不匹配最小化。此外，补偿方案始终保持较高的成功率，防止了传统方案中通常出现的移动效率逐渐丧失的情况。它还提供了更可控的垂直位移，从而减少了不必要的伸长。此外，同步的牙冠-牙根移动有助于更稳定的整体移动，确保牙齿更准确地沿着预期轨迹移动。这些发现突出了补偿方案在提高拔牙病例治疗可预测性和准确性方面的潜力。这种方法能够根据实际牙齿移动对矫治器设计进行系统调整，为透明矫治器生物力学提供了一种优化策略，并有可能改善正畸治疗的临床效果。
