Department of Orthodontics, School of Dentistry, Showa University.
Department of Mechanical Engineering, Keio University.
Dent Mater J. 2022 Oct 2;41(5):688-697. doi: 10.4012/dmj.2021-339. Epub 2022 May 27.
Orthodontic aligners undergo deformation during installation, producing an unexpected component of elastic restoring force that causes unintended changes in the dentition. The aim of this study was to investigate the relationship between strain and elastic recovery of the aligner. We distinguished the contributions to aligner deformation due to molding and installation by measuring the thickness distribution of an aligner after molding using micro-CT and tracking changes in grid patterns drawn on the sheet used to fabricate the aligner. The aligner was installed on a device that simulated canine movement. Although canine strain was quite strong around the cusp, and in premolar, it was observed mainly in their centers. Furthermore, after molding, thickness distribution of the aligner was found. But, it is no clear relationship between the thickness distribution and the strain distribution. Our method of analysis can help improve aligner design and establish molding method to deliver optimal orthodontic treatment.
正畸矫治器在安装过程中会发生变形，产生意想不到的弹性回复力分量，导致牙齿的意外变化。本研究旨在探讨矫治器应变与弹性回复之间的关系。我们通过测量微 CT 成型后矫治器的厚度分布，并跟踪用于制作矫治器的薄片上绘制的网格图案的变化，区分了成型和安装对矫治器变形的贡献。将矫治器安装在模拟犬齿运动的装置上。虽然在犬齿的牙尖和前磨牙周围，应变相当大，但主要观察到它们的中心。此外，在成型后，发现了矫治器的厚度分布。但是，厚度分布和应变分布之间没有明显的关系。我们的分析方法可以帮助改进矫治器设计并建立成型方法，以提供最佳的正畸治疗。
