三维光学扫描及快速成形技术制作面部软组织三维树脂模型的初步研究

目的应用三维光学扫描及快速成形技术制作人面部软组织三维树脂模型，为研制颌面赝复体计算机辅助设计（computer aided design，CAD）与计算机辅助制作（computer aided manufacture，CAM）系统奠定基础。方法采用自主研发的三维光学测量系统对志愿者左右侧面部分别进行扫描，通过Surfcaq软件对图像数据进行转换，获得完整的点云数据。以鼻尖点、颏下点、眼眶外侧点作为标定点，在Geomagic studio软件中对点云数据进行拼接、拟合，三维重建面部软组织。将三维重建图像导入MagiCS RP软件，进行三角化，并生成2mm的厚度，利用快速成形设备制作面部软组织三维树脂模型。结果获得了志愿者面部软组织的三维重建图像，并经快速成形制作出面部软组织三维树脂模型。结论利用三维光学扫描可进行人面部软组织三维重建，利用快速成形技术制作面部软组织三维树脂模型切实可行。     

面部软组织数字化立体摄影三维重建系统的建立

目的　研究和开发一套数字化立体摄影面部软组织三维重建系统 ,可以在计算机中重建面部三维图象。方法　应用数码相机和我们研制的一套数字化立体摄影测量硬件系统 ,在专业计算机立体显示卡上开发面部软组织三维重建和测量软件系统 ,完成面部软组织数字化摄影三维重建系统。结果　可以用显示卡立体眼镜在计算机中观看并且任意旋转、移动、缩放重建的面部软组织三维图像。结论　本研究所建立的面部软组织三维重建系统 ,可进行面部软组织三维形态的重建和数字化储存 ,为口腔正畸学面部软组织三维立体特征的诊断和研究提供了一个有效的方法     

面部软组织三维重建及测量系统的研制与应用

目的 研究和开发可应用于正畸临床诊断的数字化三维重建和测量系统,进行颌面部软组织结构的三维测量研究。方法 应用4个高精度的数码相机获取颌面部软组织的三维信息,自行研制和开发出应用于面部重建和测量的数字化立体摄影测量硬件系统,在专业计算机立体显示卡上开发面部软组织三维重建和测量软件系统,同时完成面部软组织三维测量分析和旋转观察。结果 应用研制的面部软组织三维重建和测量硬件及软件系统,可以重建出具有真实感的三维图像并在计算机中任意旋转、移动、缩放;面部软组织三维立体测量精度,左侧数码相机对为0．483mm,右侧数码相机为0．419mm。结论 本项研究所建立的面部软组织三维重建和测量系统,具有精度高、速度快、非介入性等特点,为口腔正畸学面部软组织三维结构的诊断、分析提供了一条新途径。     

基于二维DR的颅面硬组织与软组织拟合的研究

目的:以数字化X线摄影片(digital radiograph,DR)图像和激光扫描为数据源,三维重建颅面硬组织和软组织,并进行硬软组织的有效拟合,以期为治疗方案确定、手术方法选择和提高医患交流的水平提供平台.方法:在志愿者面部贴定铅点,拍摄头颅正侧位DR片.利用基于二维DR数据的颅面硬组织三维重建系统进行硬组织形变建模.获得颅面部硬组织模型.利用激光扫描数据进行面部软组织三维重建,获得面部软组织三维模型.然后通过铅点坐标的匹配,将颅面硬组织与面部软组织进行拟合.结果:分别重建了能反映真实颅面部组织结构的硬组织三维模型和面部软组织三维模型,并实现了颅面部硬组织与软组织的有效拟合.结论:本研究实现了颅颌面三维结构的有效重建和拟合,为进一步进行正颌手术模拟和容貌预测奠定了基础.拟合结果真实可靠,能够用于临床.     

面部软组织数字化三维重建及测量系统的研制与应用

目的研制和开发一套可应用于正畸临床诊断的数字化三维重建和测量系统,进行颌面部软组织结构的三维测量和研究,并可在计算机中将重建的面部三维图象进行旋转观测、储存和分析。材料方法应用4对高精度的数字相机获取颌面部软组织的三维信息,自行研制和开发出了应用于面部测量和重建的数字化立体摄影测量硬件系统,在专业计算机三维显示卡上开发出面部软组织三维重建和测量软件系统,可同时进行面部软组织三维测量分析与旋转观测。结果应用研制的面部软组织三维重建和测量的硬件和软件系统,可以重建出具有真实感的面部三维图象,并可在计算机中进行任意旋转、移动、缩放重建;建立的面部软组织三维测量系统的测量精度可达到0.5mm,足以满足口腔正畸临床诊断和治疗的需要。结论本研究所建立的面部软组织三维重建和测量系统,具有高精度、高速、非介入性等特点,为口腔正畸学临床诊断和治疗提供了一个崭新的途径。     

激光扫描在面部畸形三维重建及测量中的初步应用

目的开发建立一套面部三维结构重建、测量及诊断分析系统。方法应用系统建立标准石膏立方体试件以及石膏头像三维计算机模型并进行定点、测量,测量值与标准值比较获得系统建模误差以及定点误差范围;2例面部畸形患者进行了面部三维扫描建模,应用系统对患者面部计算机模型进行了定点、线距、角度测量以及初步对称性分析。结果三维计算机模型的建模误差在0.2 mm以内,定点误差在0.5 mm以内。应用本系统可以完成三维计算机模型的定点、线距、角度测量及对称性分析工作,基本能够达到临床要求。结论三维激光扫描技术为颌面部畸形患者面部软组织三维结构重建和非接触式测量提供了一种简便、精确、高效的方法。     

应用核磁共振(MRI)采集及三维重建面部表面软组织形态的研究

目的:对MRI在面部软组织的三维扫描与重建图像效果进行研究,以判断其在颌面重建领域中的应用价值。方法:对2名健康志愿者头部进行MRI扫描,扫描数据以DICOM格式储存。在诊断工作站上以SSD法对图像进行重建。结果:在扫描层厚较小的情况下,MRI能完成面部大部分软组织的三维扫描与重建,但图像质量较粗糙。结论:MRI能完成面部软组织的三维扫描与重建,但不应作为颌面重建首选的重建方式。     

应用激光扫描技术三维重建正常耳廓模型

目的 采用激光扫描技术获取耳廓模型的三维数据，从而在计算机内获得相应的STL文件，实现三维重建。方法 应用三维激光扫描仪，对耳廓石膏模型进行三维扫描，获取耳廓的数据，转化为相应的数据化文件，得到三维重建图像。结果 取得了相应的耳廓数据数字化图像并转化为对应的数字化文件。数字化图像的形态、大小及耳颅角度与原石膏模型一致。结论 应用三维激光扫描技术快速而准确地重建耳廓外形，为制作义耳时获取正常侧及缺损区耳廓形态提供了一种新方法．从而为更方便地制作义耳提供了可能。     

立体摄影颌面部软组织三维重建与测量的研究进展

颌面部软组织三维重建及其在此基础上的测量，在口腔颌面外科学、口腔正畸学、整形外科学、法医学、人类学及美学等领域有着很重要的意义。在面部软组织重建与测量方面，出现了激光扫描、立体摄影、莫尔云纹、结构光技术、CT、MRI等方法，但各有利弊。面部软组织三维立体摄影测量（stereopho-togrammetry）在20世纪90年代初即开始出现。     

激光扫描在头面部软组织三维重建和测量中的应用

近年来,随着科学和计算机技术的发展,人们对头面部软组织的研究已经由二维发展到三维,用于三维重建的技术也越来越多,包括直接测量法、莫尔云纹法、形态分析法、激光扫描法、结构光测量法、立体摄影测量技术、光栅投影测量法和电子计算机断层扫描技术等。其中,激光扫描是目前比较先进的技术之一。尽管受很多因素的影响,但笔者相信随着技术的不断改进和完善,激光扫描在头面部软组织三维重建中将得到更加广泛的应用。本文将从激光扫描技术的原理、技术构成、特点及其在头面部软组织三维重建方面的应用等内容进行综述。     

Three-dimensional facial simulations and measurements: changes of facial contour and units associated with facial expression

Recent innovations in laser scanning technology provide a potentially useful technique for accurate three-dimensional documentation of the face. In this study, linear and area measurements of the facial contour and facial units have been recorded in a variety of chosen facial postures using surface laser scanning combined with three-dimensional lighting techniques on seven healthy volunteers and three patients with facial nerve paralysis. Three-dimensional surface measurement of the face was taken using a laser light scanner. Computer graphics lighting techniques were used to produce facial images constituted by highlights and shadows, which emboss facial contour and units. Then quantitative measurement of changes in facial angles and areas were made to analyze morphological changes of the face accompanying facial expression. Changes of angles and widths of the cheek and nasal units were found to be associated with dimensional changes imposed by the action of the underlying mimetic muscles. This system has potential value for both dynamic monitoring and evaluation of facial contour, units, and movement.     

螺旋CT扫描重建与快速成型技术在颜面缺损赝复中的应用

目的:将螺旋CT扫描重建与三维打印快速成型技术相结合应用于颜面缺损赝复。方法:采用螺旋CT对1名颜面部颧颊联合缺损的患者进行颜面部扫描,对CT数据进行三维重建和处理,导入三维打印快速成型设备,制作患者的颜面缺损实体模型。比较、测量患者及模型的实际外形、尺寸。结果:螺旋CT扫描重建获得的颜面部三维数字化模型完整、清晰。三维模型经编辑导入三维打印快速成型机后,成功制作出颜面缺损实体模型。该模型与患者面部形态高度相似。结论:螺旋CT扫描重建结合三维打印技术,能准确获取颜面外形信息并生成颜面缺损实体模型。     

Assessment of facial tissue expansion with three-dimensional digitizer scanning

This article reports a three-dimensional (3D) digital color scanning system used in the measurement of facial soft tissue expansion. This system consists of digital scanning equipment, software for stereolithographical (STL) forms and nonuniform rational B-spline (NURBS) surfaces, and a computer-aided design program. Accurate data for the area of scar excision and the expanded cervicofacial flap were obtained by using this measuring system in a young patient with scar contracture of the face. This technique can accurately model the reconstruction and make plastic surgery planning a truly interactive procedure.     

光学测量系统在面部外形测量中的应用研究

目的 研究面部三维光学测量系统在面部外形重建和测量中的实用性和可靠性。方法 利用自行研制的面部三维光学测量系统扫描45名正常人面形，结合Geomagic studio软件反求重建面部外形。比较面部内眦间距、鼻长、鼻宽、鼻高、鼻深等的反求测量结果与手工测量结果间的差异。结果 基于面部三维光学测量系统结合反求软件直接重建了45名正常人的面部三维外形，面部测量项目的 反求测量结果与手工测量结果在统计学上无明显差异（P>0.05）。结论 面部三维光学测量系统在面部外形采集、反求重建、三维测量中具有较高的可靠性和较好的实用性。     

Three-dimensional imaging andmotion animation

Orthodontic treatment is aimed at affecting the craniofacial relationships in three planes of space. Yet strangely enough, the critical diagnostic records are two-dimensional. In an orthodontic setting, the techniques of imaging the human face in a three-dimensional manner have been either stereo photography, or projection of optical grids or the structured light. These projections enable the operator to capture the facial image in a three-dimensional manner. Unfortunately, all these methods are static in nature. The laser scanning techniques and the availability of sophisticated software for image manipulation, make image animation possible. Here we report the first ever motion animation of the human face from laser-generated images for clinical purposes.     

Reliability of optical devices for three-dimensional facial anatomy description: a systematic review and meta-analysis

The use of three-dimensional (3D) optical instruments to measure soft tissue facial characteristics is increasing, but systematic assessments of their reliability, practical use in research and clinics, outcome measurements, and advantages and limitations are not fully established. Therefore, a review of the current literature was performed on the reliability of facial anthropometric measurements obtained by 3D optical facial reproductions as compared to conventional anthropometry or other optical devices. The systematic literature search was conducted in electronic databases following the PRISMA guidelines (PROSPERO registration: CRD42018085473). Overall, 815 studies were identified, with 27 final papers included. Two meta-analyses were conducted. Tested devices included conventional cameras, laser scanning, stereophotogrammetry, and structured light. Studies measured living people or inanimate objects. Overall, the optical devices were considered reliable for the measurement of linear distances. Some caution is needed for surface assessments. All instruments are suitable for the analysis of inanimate objects, but fast scan devices should be preferred for living subjects to avoid motion artefacts in the orbital and nasolabial areas. Prior facial landmarking is suggested to improve measurement accuracy. Practical needs and economic means should direct the choice of the most appropriate instrument. Considering the increasing interest in surface-to-surface measurements, fast scan devices should be preferred, and dedicated protocols devised.     

Optical data acquisition for computer-assisted design of facial prostheses

PURPOSE: The conventional impression technique for manufacturing facial prostheses has the disadvantage of deforming the soft tissues because of the tension caused by the impression material, as well as causing discomfort to the patient. The purpose of this study was to establish a system that allows contact-free reproduction of the facial surface combined with computer-assisted design and fabrication of facial prostheses. MATERIALS AND METHODS: Three-dimensional data of the facial surface were obtained using an optical acquisition system based on the method of phase-measuring profilometry. A sensor head with a fringe projector and two CCD cameras for photogrammetric triangulation were used in connection with a PC for measurement control and data evaluation. Software for computer-assisted design of the facial surface to be reconstructed was developed. A prototype facial prosthesis was fabricated using stereolithography. The system was tested using a modified puppet head. First clinical tests were performed with a patient who had undergone maxillofacial surgery including the resection of one eye. RESULTS: Three-dimensional data acquisition and imaging allow visualization of a whole face without causing tension or neuromuscular reaction. As surface brightness is also part of the digital model, it is even more realistic than a plaster cast. The stereolithographic object showed good marginal fit and satisfactory shape. CONCLUSION: The presented technique allows three-dimensional data reproduction of the facial surface, computer-assisted design of a facial prosthesis, and transfer to a rapid prototyping unit. The system has obvious advantages over conventional impression techniques. Further clinical trials are planned to evaluate the clinical success of the technique.     

Three-dimensional imaging of the craniofacial complex

Orthodontic treatment requires the rearrangement of craniofacial complex elements in three planes of space, but oddly the diagnosis is done with two-dimensional images. Here we report on a three-dimensional (3D) imaging system that employs the stereoimaging method of structured light to capture the facial image. The images can be subsequently integrated with 3D cephalometric tracings derived from lateral and PA films (www.clinorthodres.com/cor-c-070). The accuracy of the reconstruction obtained with this inexpensive system is about 400 μ.     

新型婴儿唇裂仿真模型及其在外科手术教学中的应用

目的:探索建立一种新型婴儿唇裂面部仿真模型与制作方法,为唇裂个性化术前模拟与外科仿真教学提供帮助.方法:通过新型可见光人体三维扫描仪对3个月龄唇裂患儿面部扫描直接获取光学印模,应用逆向工程软件处理原始数据并设计出唇裂婴儿面部三维数据模型,然后利用快速成型技术将其直接加工出修复体的树脂模型,最后通过颌面赝复技术制作出婴儿唇裂仿真硅橡胶模型.结果: 首次成功设计并制作出个性化、高仿真的3个月龄婴儿唇裂面部硅橡胶仿真模型,并成功地用于唇裂术前模拟与教学.结论: 通过综合应用多种新型数字化技术与颌面赝复材料与技术,可以设计并制作出新生儿唇裂仿真模型,该模型具有良好的临床与教学应用前景.