建立数字化颅颌运动系统的初步研究

目的探索建立数字化颅颌运动系统的方法。方法根据三维激光扫描图像、螺旋CT图像重建包括牙齿、髁突和关节窝的三维数字模型；利用ARCUS digma系统获取下颌运动轨迹，并将三维数字模型和运动轨迹导入同一坐标系中；编写数字化颅颌运动软件。结果实现了静止和下颌运动状态下关节与牙列三维数字模型的动画模拟、接触点检测、多角度观察及断层观察；尝试了对（牙合）平面、（牙合）曲线、螺旋轴等进行显示。结论初步建立了数字化颅颌运动系统，实现了颅颌运动的三维显示和模拟，为数字化颅颌运动系统的进一步研究奠定了基础。     

偏颌畸形下颌开闭口运动特征的研究

目的 研究发育性偏颌畸形患者下领开闭口运动的特点，探讨偏颌畸形对下颌运动功能的影响。方法 采用下颌运动轨迹描记仪(Sirognathograph,SGG)采集28例偏颌畸形者及41例咬合正常者最大开闭口运动的三维方向时间—位移信号，比较两组受试者下颌运动轨迹的形态、开闭口运动的位移及速度等参数的差异。结果 偏颌畸形患者开闭口运动轨迹在冠状面内主要分布在患侧，下颌向患侧移动的幅度明显大于向健侧移动的幅度，开口运动中下颌偏离中轴的程度较闭口运动时明显。偏颌者下颌开闭口运动三维空间内的位移、速度比正常咬合者大。结论 偏颌患者下颌运动处于能量消耗较高的状态，下颌运动功能的异常可能影响口颌系统的功能。     

下颌运动轨迹研究方法及应用

下颌运动是由[牙合]、咀嚼肌及颞下颌关节共同参与进行的一种复杂三维运动，对于我们行使并认识咀嚼、吞咽及语言等功能具有十分重要的意义．因此，近年来对下颌运动的研究已成为各国学者们研究的热点。本文拟对下颌运动轨迹研究技术的发展及其在口腔医学中的应用作一回顾。     

健康人下颌运动速度,加速度的研究

利用Ｄ－ＳＧＧ下颌运动轨迹分析仪，测试２５名正常ｈｅ青年在边缘运动、习惯运动、功能运动中下颌珠运动速度及加速度值。根据结果，作者首次提出下颌运动的“功能速度“和“极限速度”的概念及其生理意义。本文还首次应用第二定律：Ｆ＝ｍａ，来解释下颌运动加速度值的生理及临床意义。并提出在咀嚼。运动中，机体在咀嚼速度之间的分配上，采取的是“速度优先”的原则来保证必须的咀嚼效率。     

下颌三维定位技术指导下稳定型殆垫治疗颞颌关节紊乱病的疗效分析

目的：探讨超声三维下颌定位技术指导下修正性调磨的骀垫对TMD的临床疗效。方法：本研究从北京口腔医院颞颌关节门诊2003年3月～2008年12月就诊的患者选用40例（男12例女28例）颞颌关节病并有关节绞锁的患者，超声三维下颌定位仪中的髁突运动中心电子位置分析（electronicpositionanalysis，EPA）检测指导下进行修正性调磨骀垫治疗后，比较治疗前后下颌运动程度如张口度、关节绞锁运动、弹响和下颌运动疼痛的变化情况。结果：本研究发现超声三维下颌定位技术指导下修正性调磨的殆垫治疗后，下颌运动明显改善，张口运动及被动最大张口度治疗前后均有显著性差异；绞锁运动症状明显改善。并有统计学差异。结论：超声三维下颌定位技术指导下修正性调磨的黯垫治疗TMD，能够改善TMD症状，在治疗绞锁运动方面有显著疗效。     

深覆He患者升高垂直距离修复的下颌运动功能评价

目的：评价行垂直距离升高修复后下颌运动功能的变化。方法：对8例深覆He患在升高垂直距离修复前后进行切点下颌运动轨迹的描记和分析。结果：升高垂直距离后，开闭口和前伸边缘运动中垂直运动幅度有一定程度的减小；侧方接触滑动时，左右侧向运动幅度明显增加；咀嚼运动的各向运动幅度均有显性增加。结论：深覆He患升高垂直距离能改善下颌运动功能。     

Zebris下颌运动分析系统的应用与研究现状

下颌运动轨迹记录是一项重要的临床技术,它能够帮助医师了解下颌运动的过程及原理,诊断疾病及评估干预手段的疗效。Zebris下颌运动分析系统作为近年来逐渐推广应用的下颌运动轨迹记录系统,具有其特殊的优势。本文对Zebris下颌运动分析系统的工作原理及方式进行了介绍,并综述其应用。     

联合动态MRI和下颌运动轨迹描记仪分析健康人开闭口时下颌运动轨迹特征

目的：结合动态MRl分析健康人开闭口时下颌运动轨迹特征。方法：18例健康人最大开闭口过程进行动态MRI和下颌运动轨迹描记仪检查，分析髁状突及下颌前牙切点的运动特点及范围。结果：动态MRI显示闭口位关节盘本体部呈双凹形，本体部位于髁状突横嵴的前方（盘分界角〈10。）。健康人下颁前牙切点运动轨迹平滑，双侧运动中心运动轨迹左右对称；运动轴始终保持平行，呈现开闭口初、末时密度比开闭口中时大；运动中心运动距离（13．2±3．1）mm，切点运动距离（41．1±3．8）mm。结论：下颌运动轨迹描记能记录髁状突运动轨迹并且间接反映颞下颌关节的关节盘在开闭口运动中的位置变化情况，为初步建立下颌运动轨迹描记对辅助诊断关节病的参考标准奠定了基础。     

下颌运动轨迹的计算机处理系统

本文借助于计算机定量分析,着重介绍了下颌运动轨迹信号的特点,三维投影图显示,位移及速度等基本参数的提取方法。介绍了在IBM—PC/XT上实现的对下颌运动轨迹处理的微机系统.包括硬件配置,软件的基本功能,采样图形处理和参数提取程序的基本结构等有关问题.     

功能性矫治器矫治安氏Ⅱ类Ⅰ分类错下颌运动轨迹初步分析

本文通过选用下切牙区下颌运动的描记，探讨用ＦＲＩ矫治器矫治安氏ⅡⅠ错，下颌运动的变化，发现型对下颌边缘运动具有引导作用，随着矫治后深覆的改善，运动轨迹随之改变；通过矫治使下颌运动轨迹重复性增加，说明下颌运动可作为一种功能监测手段，帮助分析、诊断、评价正畸疗效     

Wireless optoelectronic recordings of mandibular and associated head-neck movements in man: a methodological study

Human mandibular movements in space are the result of combined motions of the mandible and the head-neck. They can be simultaneously monitored by an optoelectronic recording technique via markers at different locations on the mandible and on the head. Markers can be attached to the teeth or to the facial skin. Mandibular movements relative to the head can be calculated by one- or three-dimensional (1D and 3D, respectively) mathematical compensation for head movements. The present study analysed mandibular and associated head movements during maximal jaw opening-closing tasks in 10 healthy subjects using a wireless 3D optoelectronic movement recording system. The study aimed to: (i) estimate the soft tissue related displacement of skin-attached markers at different locations on the face; (ii) compare 1D with 3D mathematical compensation for associated head movements; (iii) evaluate the influence of marker location on the recorded head and mandibular movement amplitudes; and (iv) compare skin-attached markers with teeth-attached markers with regard to temporal estimates of recorded mandibular and head movements. Markers were attached to the upper and lower incisors and to the skin of the forehead, nose-bridge, nose-tip and chin. Soft tissue related displacement of skin-attached markers varied between locations. The displacement for the chin marker was larger than that of other markers. The least displacement was found for the nose-bridge marker. However, relative to mandibular and head movements, respectively, the displacement of the chin marker was of the same order as that of the nose-bridge marker. The temporal estimates were not significantly affected by displacement of the skin-attached markers. Markers at different locations on the head and the mandible registered different amplitudes. The mandibular movement patterns calculated by 1D and 3D compensation were not comparable. It is concluded that markers attached to the chin and the nose-bridge can be reliably used in temporal analyses of mandibular and head movements during maximal jaw opening-closing. With certain limitations, they are acceptable for spatial analyses. Selection of method of marker attachment, marker location, and method of compensation for associated head movements should be based on the aim of the study.     

Study on the reconstruction of a four-dimensional movement model and the envelope surface of the condyle in normal adults

The objective of this study was to reconstruct the envelope surface of the condyle and the four-dimensional trajectory model in mandibular border movement in normal adults. Eleven healthy subjects were selected as volunteers. Cone-beam computed tomographic (CBCT) scanning was performed on the volunteers. The three-dimensional (3D) movement path of the mandible was recorded using a virtual articulator (PN-300), which was based on a 3D model of the mandible. We used Proplan CMF 3.0 (Materialise) software to perform this from the DICOM data generated by CBCT scans. The distance of condylar movement was measured in this model during volunteers’ mouth opening, protrusion, and lateral excursions. The envelope surface of the condyle was reconstructed by merging a functional condylar surface at each recording moment during the movement of the whole border. In the mandibular digital models, the condyle moved downward firstly, and moved upward to the position of maximum mouth opening. The condyle moved forward and downward during protrusion. The working condyle rotated slightly and the non-working condyle moved forward, downward, and inward during lateral excursions. The mean (SD) movement distance of 11 subjects was 19.04 (4.37) mm during mouth opening (including downward and upward) and 9.75 (2.38) mm during protrusion. During lateral excursions the mean (SD) movement distance of the working condyle was 2.87 (1.13) mm, the mean (SD) movement distance of the non-working condyle was 10.85 (3.25) mm. The envelope surface of healthy volunteers showed a double-peak pattern. The envelope surface of the condyle and four-dimensional movement model can be reconstructed by merging the trajectory of the mandible recorded from the novel virtual articulator PN300 and a 3D image of the mandible.     

下颌第一磨牙平台转移种植体三维有限元模型的建立

目的 构建下颌第一磨牙平台转移种植体的三维有限元模型.方法 选择健康成年男性下颌骨1例进行螺旋CT扫描,将得到的DICOM数据导入Mimics 10.01软件中,建立下颌骨及牙齿的三维几何模型,并用Geomagic studio12软件进行曲面优化;利用UG NX6.0软件建立平台转移种植系统(韩国DIO种植体系统)的三维几何模型;最后将各部分模型导入Hypermesh10.0软件中进行装配组合、网格划分以及材料属性赋值.结果 成功建立了下颌第一磨牙平台转移种植体的三维有限元模型,该模型与实际模型有高度的几何相似性,其网格质量较高、力学性能好.结论 结合CT扫描技术和多种有限元建模软件能够快速、精确地建立下颌第一磨牙平台转移种植体的三维有限元模型,为后续平台转移种植体进行有效的生物力学研究提供基础.     

Recording of the retruded position of the mandible in patients with mandibular dysfunction.

The precision (reproducibility) of active and passive recordings of the retruded position of the mandible was studied by two examiners on 10 patients with mandibular dysfunction symptoms. The position of the mandible was recorded with an intra-oral graphic method, before and after treatment of the symptoms. The precision of the recording was highest when the retruded position was recorded by passive hinge movement and lowest when it was recorded by active hinge movement and when recording habitual closure. Both systematical and accidental errors tended to be somewhat larger among these patients than that previously found among individuals without signs or symptoms of mandibular dysfunction. The accidental errors in antero-posterior and medio-lateral directions were the same fo both examiners and of the same magnitude before and after treatment of the symptoms. Both examiners recorded the retruded position on the average 0.20 mm more posterior after treatment than before. The results showed that because of its good reproducibility the retruded position of the mandible can be recommended as a reference position in functional analysis of occlusion and for jaw recordings also in patients with TMJ muscle-pain dysfunction symptoms. During the recording the conventional technique with passive hinge movement and a posterior pressure should be used.     

A digital approach to dynamic jaw tracking using a target tracking system and a structured-light three-dimensional scanner

Purpose

This technical procedure describes a method for tracking mandibular movement using a three-dimensional (3D) optical scanner and target tracking system to digitally portray the motion of the mandible and temporomandibular joints by merging cone beam computed tomography (CBCT) data.

应用Mimics和HyperMesh软件建立人体下颌骨三维有限元模型

目的:探讨一种快速、精确的正常人下颌骨三维有限元建模方法。方法:对1名牙列完整、咬合关系正常的男性志愿者进行颌骨螺旋CT扫描,将获取的Dicom格式数据在Mimics 10.01软件中进行完整下颌骨3D重建,将所得的下颌骨三维几何模型转换成iges格式后,导入HyperMesh软件中完成网格划分及对材料属性进行赋值,最后导入ABAQUS 6.9对模型边界约束条件进行限制,生成完整下颌骨的三维有限元模型。结果:快速地建立了更加精确的人体完整下颌骨的三维有限元模型。联合运用HyperMesh软件和Mimics软件对下颌骨进行建模,大大提高了建模的速度以及模型的质量。结论:应用Mimics和HyperMesh软件可以快速、精确的建立人体下颌骨的三维有限元模型,为进一步的生物力学分析打下基础。     

数字化可视下颌骨的初步研究

目的建立数字化可视下颌骨的三维实体模型。方法将1例人体标本固定、灌注、冷冻、包埋、切削,选取从颏部到下颌骨髁突图像,通过摄像采集数据,描取每层下颌骨的皮质骨外形、牙齿及牙槽窝轮廓线及下颌管,各层轮廓线均形成闭合曲线。利用Amira软件系统进行下颌骨的外形及下颌管的重建,得到三维线框模型和实体模型。结果利用数字人数据得到下颌骨精细的三维模型,在三维空间上真实再现了下颌骨、下颌牙的解剖形态,并准确地显示出下颌神经管的位置。结论采用软件重建方法获得的下颌骨三维模型,为下颌骨的影像诊断及正颌外科手术治疗、下颌牙齿种植等提供了解剖学依据。     

A development of data analyzing system for the mandibular movement

Recent developments in medical engineering has made it easy to record biological phenomena. Furthermore, the widespread popularity of the personal computer has made data processing system remarkably efficient. In this study, an efficient personal computer system for mandibular movement analysis is investigated, and a data analyzing system for that movement developed. Applying this system to chewing movements in a small number of cases made possible efficient, easy and accurate analysis. The following is an outline of the system and its applicability. 1. Standard measuring coordinate system for mandibular position and designation of mandibular position measuring point An orthogonal coordinate system is used to the standard measuring coordinate system for mandibular position measurement coordinates. The X axis of this orthogonal coordinate system is determined as a straight line connecting two LEDs. The origin point is designated as the center between two LEDs. This connects with the upper dentition or the maxilla. The mandibular position measuring point is designated on the orthogonal coordinate system. The X axis of this orthogonal coordinate system is determined as a straight line connecting two LEDs. The origin point is designated as the center between two LEDs. This connects with the lower dentition or the mandible. The analysis of mandibular position of designated measuring point on the lower dentition or the mandible is performed corresponding to the orthogonal coordinate system on the upper dentition or the maxilla. 2. Calculation of coordinates value [mm] for mandibular position measuring point In the analysis, value [V] for the distance between two LEDs established on the upper jaw is substituted for the already input real distance [mm] between two LEDs. The coordinates value of the mandibular position measuring point is calculated from these substitution value. 3. Data recording Data concerning mandibular movement and myoelectric discharges are recorded by means of a data recorder. Digital data are converted to analogue data from the data recorder by means of a 12-bit A/D converter and they are accumulated in the memory of the personal computer system. Digital data in the memory of the personal computer system can be stored in about 97 seconds for the storage capacity of a floppy disk (2HD) memory area.     

偏侧咀嚼对张闭口运动的影响

目的:分析偏侧咀嚼患者在最大张闭口运动中的下颌运动轨迹特征。方法:通过下颌运动轨迹描记检测技术,比较偏侧咀嚼和正常咀嚼人群在大张口运动中的运动轨迹,进行统计分析。结果:1)偏侧咀嚼组在大张口运动时开闭口轨迹多数分离,开口型与与双侧咀嚼组相比差异有统计学意义(P<0.05)。2)偏侧咀嚼组张闭口运动时垂直向和矢状向位移显著低于双侧咀嚼组(P<0.01)。结论:最大张闭口运动中偏侧咀嚼组开口型多数偏向工作侧,50%的人群开闭口轨迹分离,开口度减小,说明长期偏侧咀嚼会导致张闭口运动轨迹的异常。     

Denture mobility with six degrees of freedom during function

SUMMARY The purpose of this study was (1) to assemble and verify a system to measure the three‐dimensional (3‐D) movement of the upper and lower complete dentures and the movement of the mandible simultaneously, and (2) to analyse the relation between denture movements and the path of closure of the mandible during function. A 3‐D motion capture system with four infrared TV cameras was used for this purpose. The relation between the dentures and the mandibular movements was analysed through the change of the inner product of normal vectors of the denture occlusal planes and mandibular planes. The mandibular movements were classified into two types the normal stroke (the path of closure was on the ipsilateral side of mastication) and the reverse stroke (on the contralateral side). The results showed that the system could measure the denture mobility within a 0·3 mm error. The mobility of the upper dentures had a correlation to the path of closure of the mandible regardless of the working side or nonworking side, and the lower dentures had a tendency to move toward the working side.