安氏II类1分类伴下颌后缩生长发育期患者Twin Block矫治后上气道反应的流体动力学仿真模拟

There are varying degrees of stenosis in growing patients with Class II Division 1 and mandibular retrognathia. Twin Block (TB) functional appliance is one of the first choices in correcting this type of malocclusion. However, previous studies mostly focused on the changes in craniomaxillofacial and two-dimensional morphology of the upper airway, there have been no reports related to the computational fluid dynamics (CFD) response of the upper airway to TB treatment. We have innovatively achieved the controlled evaluation of pharyngeal three-dimensional (3D) morphological changes due to TB treatment. The objective of this study is to further evaluate the upper airway CFD response to TB treatment and verify the validity of the CFD methods through in vitro airflow simulation in upper airway 3D models, investigate the change mechanism of airflow in the upper airway, analyze the correlation between the upper airway morphology and respiratory function, and explore the most sensitive morphological parameter which related to respiratory function on the basis of our previous morphological evaluation of the upper airway. This study might clarify the CFD change rules of the upper airway due to TB treatment in growing patients with Class II Division 1 and mandibular retrognathia and provide important theoretical basis for the upper airway respiratory function improvement by clinical treatment of malocclusion.

安氏II类1分类伴下颌后缩生长发育期患者上气道均存在不同程度狭窄，Twin Block功能矫治器成为其临床矫治的首选方法之一，但Twin Block的治疗评价主要集中于患者颅颌面形态及上气道二维形态改变，Twin Block对患者上气道的流体力学影响尚无相关研究。项目组前期已创新性实现Twin Block矫治前后患者上气道的三维形态学对照研究，本课题拟进一步对患者上气道流体动力学变化进行模拟，并通过构建体外上气道模型进行体外气流模拟，验证流体动力学模型方法的有效性，探讨治疗前后上气道内气流流场的改变机制；结合前期上气道形态学变化的研究结果，分析上气道解剖形态与通气功能的相关关系，探索导致上气道通气功能变化最敏感的形态学指标。本研究有望阐明安氏II类1分类伴下颌后缩患者Twin Block矫治后上气道气流的流体动力学变化规律，为临床通过错颌畸形的矫治改善患者上气道通气功能提供重要理论依据。

安氏II类1分类伴下颌后缩生长发育期患者上气道均存在不同程度狭窄，Twin Block功能矫治器成为其临床矫治的首选方法之一，但Twin Block的治疗评价主要集中于患者颅颌面形态及上气道二维形态改变，Twin Block对患者上气道的流体力学影响尚无相关研究。本课题组通过对Twin Block矫治前后患者上气道的三维形态学对照研究以及上气道流体动力学变化进行模拟，探讨了治疗前后颅颌面部的形态学变化和上气道内气流流场的改变机制；并进一步了分析上气道解剖形态与通气功能的相关关系，探索导致上气道通气功能变化最敏感的形态学指标。研究结果发现，（1）患者TB矫治后上气道口咽部及喉咽部尺寸增大，口咽部形态趋于椭圆形且区域分布更加一；（2）随着口咽部形态的改善，患者上气道内气流阻力降低，气道通气功能显著提高。 本研究初步阐明了安氏II类1分类伴下颌后缩患者Twin Block矫治后上气道气流的流体动力学变化规律，为临床通过错颌畸形的矫治改善患者上气道通气功能提供重要理论依据。