Park Jong-Tae, Lee Jae-Gi, Won Sung-Yoon, Lee Sang-Hee, Cha Jung-Yul, Kim Hee-Jin
Division of Anatomy and Developmental Biology, Department of Oral Biology, Human Identification Research Center, Brain Korea 21 Project, College of Dentistry, Yonsei University, Seoul, South Korea.
J Craniofac Surg. 2013 Jul;24(4):e347-51. doi: 10.1097/SCS.0b013e31828f2d73.
Masticatory muscles are closely involved in mastication, pronunciation, and swallowing, and it is therefore important to study the specific functions and dynamics of the mandibular and masticatory muscles. However, the shortness of muscle fibers and the diversity of movement directions make it difficult to study and simplify the dynamics of mastication. The purpose of this study was to use 3-dimensional (3D) simulation to observe the functions and movements of each of the masticatory muscles and the mandible while chewing. To simulate the masticatory movement, computed tomographic images were taken from a single Korean volunteer (30-year-old man), and skull image data were reconstructed in 3D (Mimics; Materialise, Leuven, Belgium). The 3D-reconstructed masticatory muscles were then attached to the 3D skull model. The masticatory movements were animated using Maya (Autodesk, San Rafael, CA) based on the mandibular motion path. During unilateral chewing, the mandible was found to move laterally toward the functional side by contracting the contralateral lateral pterygoid and ipsilateral temporalis muscles. During the initial mouth opening, only hinge movement was observed at the temporomandibular joint. During this period, the entire mandible rotated approximately 13 degrees toward the bicondylar horizontal plane. Continued movement of the mandible to full mouth opening occurred simultaneously with sliding and hinge movements, and the mandible rotated approximately 17 degrees toward the center of the mandibular ramus. The described approach can yield data for use in face animation and other simulation systems and for elucidating the functional components related to contraction and relaxation of muscles during mastication.
咀嚼肌与咀嚼、发音和吞咽密切相关，因此研究下颌和咀嚼肌的特定功能及动力学具有重要意义。然而，肌肉纤维较短且运动方向多样，使得研究和简化咀嚼动力学变得困难。本研究的目的是使用三维（3D）模拟来观察咀嚼时各咀嚼肌和下颌骨的功能及运动。为了模拟咀嚼运动，从一名韩国志愿者（30岁男性）获取了计算机断层扫描图像，并对颅骨图像数据进行了3D重建（Mimics；Materialise，鲁汶，比利时）。然后将3D重建的咀嚼肌附着到3D颅骨模型上。基于下颌运动路径，使用Maya（Autodesk，圣拉斐尔，加利福尼亚州）对咀嚼运动进行动画制作。在单侧咀嚼时，发现下颌骨通过收缩对侧翼外肌和同侧颞肌向功能侧横向移动。在初始张口时，颞下颌关节仅观察到铰链运动。在此期间，整个下颌骨向双侧髁突水平面旋转约13度。下颌骨继续运动至完全张口时，同时发生滑动和铰链运动，下颌骨向下颌支中心旋转约17度。所描述的方法可为面部动画和其他模拟系统提供数据，并有助于阐明咀嚼过程中与肌肉收缩和舒张相关的功能成分。
