Department of Orthodontics, Shandong Provincial Hospital Affiliated to Shandong First Medical University, 324 Jingwu Road, Jinan, Shandong, China.
PingYi Country Hospital of Tranditional Chinese Medicine, Jinan, Shandong, China.
Clin Oral Investig. 2024 Nov 7;28(12):630. doi: 10.1007/s00784-024-06029-y.
The aim of this study was to evaluate the changes of upper airway ventilation function after molar distalization with aligners in adult patients by computational fluid dynamic simulation.
A total of 15 subjects were included (3 males and 12 females, with an average age of 20.00 ± 0.50 years) who required en masse distal movement of the whole dentition using Invisalign aligners. The software Mimics 19.0 was used to reconstruct the upper airway based on their CBCT images and measure the minimum cross-sectional area and volume before and after treatment. Then the upper airway flow during inspirations was simulated and evaluated using Ansys software. At last, the morphologic and hydrodynamic parameters before and after treatment were compared using paired T-test.
For morphological evaluation, the volume changes of velopharynx, glossopharynx and hypopharynx volume revealed no statistically significance after treatment compared to the data before treatment, the minimum cross section of upper airway decreased significantly. For hydrodynamics parameters, the minimum pressure, maximum shear force, velopharynx and glossopharynx pressure drop increased 50.2 Pa, 0.66 Pa, 5.78 Pa and 5.32 Pa respectively. At last, the correlation analysis between CFD data and MCA is of no statistical significance.
Non-extraction molar distalization using invisible aligners and mini-screws may lead to adverse changes in upper airway fluid dynamics, potentially increasing the risk of pharyngeal collapse.
The combination of invisible appliances with anchorage implants for the distalization of maxillary and/or mandibular teeth has emerged as a prevalent orthodontic technique. Clinicians should consider the potential impact on respiratory function when contemplating such treatment for patients with pre-existing respiratory conditions or those at a higher risk of ventilation issues.
本研究旨在通过计算流体动力学模拟评估成人患者用矫正器远移磨牙后上气道通气功能的变化。
共纳入 15 名受试者（3 名男性，12 名女性，平均年龄 20.00±0.50 岁），他们需要使用 Invisalign 矫正器整体远移整个牙列。使用 Mimics 19.0 软件根据他们的 CBCT 图像重建上气道，并测量治疗前后的最小横截面积和体积。然后使用 Ansys 软件模拟上气道吸气期间的气流并进行评估。最后，使用配对 T 检验比较治疗前后的形态和流体动力学参数。
在形态学评估方面，与治疗前相比，治疗后软腭后区、舌后区和下咽体积的变化无统计学意义，上气道最小横截面积显著减小。在流体动力学参数方面，最小压力、最大剪切力、软腭后区和舌后区压力降分别增加了 50.2Pa、0.66Pa、5.78Pa 和 5.32Pa。最后，CFD 数据与 MCA 的相关性分析无统计学意义。
使用隐形矫正器和微型种植体进行非拔牙磨牙远移可能导致上气道流体动力学的不利变化，增加咽腔塌陷的风险。
隐形矫治器结合种植体支抗用于上颌和/或下颌牙齿的远移已成为一种流行的正畸技术。当考虑对有潜在呼吸问题或通气问题风险较高的患者进行此类治疗时，临床医生应考虑其对上呼吸道功能的潜在影响。
