Stress and displacement patterns in the craniofacial skeleton with rapid maxillary expansion: A finite element method study
Stress and displacement patterns in the craniofacial skeleton with rapid maxillary expansion: A finite element method study
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DOI：
10.1016/j.ajodo.2006.09.044
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发表时间：
2007-07-01
影响因子：
3
通讯作者：
Adhikari, Raviraj
中科院分区：
文献类型：
--
作者：
Gautam, Pawan;Valiathan, Ashima;Adhikari, Raviraj
简介：本有限元研究的目的是评估应力分布沿着颅面缝和位移的各种颅面结构与快速上颌扩大（RME）治疗。研究方法：这项研究的分析模型是从连续的计算机断层扫描图像，在2.5毫米的间隔，一个干燥的年轻人的头骨。随后，通过使用AutoCAD软件（2004版本，Autodesk，Inc，圣拉斐尔，加利福尼亚州）和ANSYS软件（版本10，Belcan Engineering Group，Downers格罗夫，伊利诺伊州）从计算机断层摄影图像开发有限元方法模型。结果：上颌骨对RME的反应是向前、向下移动和顺时针旋转。翼板向外侧移位。颅面骨的远端结构--颧骨、颞骨和额骨--也受到横向矫形力的影响。上颌骨在X方向上的旋转中心位于外侧翼板和内侧翼板之间。在额面上，上颌骨的旋转中心大致位于上级眶裂。发现最大von Mises应力沿着额上颌、鼻上颌和额鼻缝。沿同一缝线沿着可显示拉伸和压缩应力。结论：RME有利于上颌磨牙区和尖牙区的扩张。它也会导致上颌骨向下和向前移位，因此有助于矫正轻度III类错牙合。下移位和后旋转的上颌骨可能是一个问题，患者过度低前面高度。高应力沿着深部结构和颅面骨骼的各种缝表示的作用，上下颌骨缝系统在向下和向前位移的上颌骨后RME。
Introduction: The purpose of this finite element study was to evaluate stress distribution along craniofacial sutures and displacement of various craniofacial structures with rapid maxillary expansion (RME) therapy. Methods: The analytic model for this study was developed from sequential computed tomography scan images taken at 2.5-mm intervals of a dry young human skull. Subsequently, a finite element method model was developed from computed tomography images by using AutoCAD software ( 2004 version, Autodesk, Inc, San Rafael, Calif) and ANSYS software ( version 10, Belcan Engineering Group, Downers Grove, Ill). Results: The maxilla moved anteriorly and downward and rotated clockwise in response to RME. The pterygoid plates were displaced laterally. The distant structures of the craniofacial skeleton-zygomatic bone, temporal bone, and frontal bone-were also affected by transverse orthopedic forces. The center of rotation of the maxilla in the X direction was somewhere between the lateral and the medial pterygoid plates. In the frontal plane, the center of rotation of the maxilla was approximately at the superior orbital fissure. The maximum von Mises stresses were found along the frontomaxillary, nasomaxillary, and frontonasal sutures. Both tensile and compressive stresses could be demonstrated along the same suture. Conclusions: RME facilitates expansion of the maxilla in both the molar and the canine regions. It also causes downward and forward displacement of the maxilla and thus can contribute to the correction of mild Class III malocclusion. The downward displacement and backward rotation of the maxilla could be a concern in patients with excessive lower anterior facial height. High stresses along the deep structures and the various sutures of the craniofacial skeleton signify the role of the circummaxillary sutural system in downward and forward displacement of the maxilla after RME.