MOE Key Laboratory of Dynamics and Control of Flight Vehicle, School of Aerospace Engineering, Beijing Institute of Technology, Beijing, 100081, People's Republic of China.
Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, 100081, People's Republic of China; Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, 100081, People's Republic of China.
J Biomech. 2022 Jun;139:111143. doi: 10.1016/j.jbiomech.2022.111143. Epub 2022 May 20.
Assessment of mandibular dynamics is essential for examining stomatognathic functions, and many kinds of stomatognathic diseases, such as temporomandibular joint (TMJ) disorder and jaw tumors, require individual diagnosis and rehabilitation treatments. Musculoskeletal models of the mandible system provide an efficient tool for fulfilling these tasks, but most existing models are generic, without direct correlation to subject-specific data. For this reason, the objective of this study was to establish a subject-specific mandible modeling framework based on clinical measurements, including medical imaging, jaw kinematics, and electromyographic (EMG) acquisition. First, a non-rigid iterative closest point method was performed to register muscle insertion sites. A flexible multibody approach was introduced to describe the large deformation behavior of jaw muscles. The EMG signals of the temporalis and masseter muscles were then utilized to determine their active forces. Meanwhile, a feedback loop for tracking desired mandibular kinematics was presented to calculate the activations of jaw opening and pterygoid muscles. The subject-specific muscle forces and TMJ joint loading during jaw opening-closing movements were then calculated based on forward-inverse coupling dynamics procedure. As a validation of the proposed framework, the mandible trajectories of seven healthy subjects were predicted and compared with experimental data. The results demonstrated unintentional movement of the head-neck complex together with the activation patterns of jaw opening and lateral pterygoid muscles for different people. The proposed framework combines musculoskeletal modeling with dental biomechanical testing, providing an efficient method of predicting and understanding the dynamics of subject-specific mandible systems.
下颌动力学的评估对于检查咀嚼功能至关重要，许多咀嚼疾病，如颞下颌关节（TMJ）紊乱和颌骨肿瘤，需要进行个体化诊断和康复治疗。下颌系统的肌肉骨骼模型为完成这些任务提供了一种有效的工具，但大多数现有的模型都是通用的，与特定于个体的数据没有直接关联。因此，本研究的目的是建立一个基于临床测量的下颌的特定于个体的建模框架，包括医学成像、下颌运动学和肌电图（EMG）采集。首先，使用非刚性迭代最近点方法来注册肌肉插入点。引入了一种灵活的多体方法来描述下颌肌肉的大变形行为。然后利用颞肌和咬肌的 EMG 信号来确定它们的主动力。同时，提出了一个跟踪期望下颌运动学的反馈回路，以计算开口和翼内肌的激活。然后基于正向-反向耦合动力学过程计算下颌开口-闭合运动期间的特定于个体的肌肉力和 TMJ 关节载荷。作为所提出框架的验证，预测了七个健康受试者的下颌轨迹并将其与实验数据进行了比较。结果表明，不同人头部-颈部复合体的无意识运动以及开口和翼外肌的激活模式。所提出的框架将肌肉骨骼建模与牙齿生物力学测试相结合，为预测和理解特定于个体的下颌系统动力学提供了一种有效的方法。
