颜面缺损赝复数字化诊疗体系

传统的颜面缺损赝复诊疗过程复杂、效率低,且美观及精度差,无法满足患者的要求。20世纪90年代开始,计算机辅助设计和制作技术的引入开创了颜面缺损赝复诊疗技术发展的新篇章。经过10多年的研究与发展,已逐步形成一套颜面缺损赝复数字化诊疗体系,该体系包括：颜面缺损信息的数字化采集、赝复体的计算机辅助设计和赝复体快速成型加工。随着该体系的进一步完善,必将成为颜面缺损赝复诊疗的发展方向与主流技术。     

自制栓道式附着体在面颊颌缺损修复中的应用

目的:探讨自制栓道式附着体在面颊缺损修复中的应用.方法:对1例颜面颌骨复杂缺损患者,通过设计栓道式附着体,连接面颊赝复体和口内赝复体,完成牙列、上颌骨及右面颊缺损的联合修复.结果:面颊赝复体和口内赝复体固位良好,患者容貌恢复较好,咀嚼功能得到提高.结论:自制栓道式附着体在颜面颌骨复杂缺损修复方面有较大的应用价值.     

颌面赝复治疗的进展

目的: 围绕近年来颌面赝复的发展进行综述与展望,为开创颌面缺损修复的新篇章提供借鉴。方法: 根据28篇代表性中英文文献（近五年文献为18篇）阐述的有关颌面赝复固位技术的发展、颜面缺损的即刻（种植）修复、颌面赝复体的数字化设计及制作三大领域的最新进展,进行总结归纳。结果: 颌面赝复是进行颌面缺损修复重建的主要方式之一。随着多种先进技术、新型材料的融合应用,现代颌面修复重建的水平得到了显著的提高。结论: 传统的以“替代”为典型代表的颌面缺损赝复已逐渐不能满足日益发展的社会需求,而以“重建”为标志的新的颌面缺损修复理念和技术成为当今的主流趋势。     

应用相位测量轮廓技术重建面部睁眼三维数字化模型

目的：建立活体睁眼状态下的面部三维数字化模型,为颌面缺损的仿真修复奠定基础。方法：采用3D CaMaga人体三维彩色数字化系统对面部进行活体测量,获得三维点云数据,运用CloudForm反求工程软件对数据进行处理后,转化为相应的数字化文件格式,在Geomagic实体构造软件中重建面部三维数字化模型。结果：成功建立了面部睁眼状态下的三维数字化模型。结论：应用相位测量轮廓术可快速准确安全的重建真实的面部三维形态,该方法在颜面赝复、口腔颌面外科、正畸科、整形外科都将有广阔的应用前景。     

面部微笑表情状态三维数字化模型的建立

目的：建立微笑表情状态下的面部蔓维数字化模型,为颌面缺损的仿真修复奠定基础。方法：采用3DCaMaga人体三维彩色数字化系统对微笑表情状态下的面部进行活体测量,获得三维点云数据,在实体构造软件中重建微笑表情状态面部三维数字化模型。结果：成功建立了微笑表情状态下的面部三维数字化模型。结论：应用相位测量轮廓术可快速准确地重建微笑表情的面部三维数字化模型,为颜面赝复体的多样化制作提供切实可行的解决方法。     

颜面赝复体粘接剂的研究进展

粘接固位是颜面赝复体的重要固位方式之一,粘接性能和生物学性能是赝复体粘接剂的两个主要性能.赝复体粘接剂有广泛的临床应用前景,但在评价实验的标准化和赝复体粘接剂性能的改进等方面还需进一步研究.本文对赝复体粘接剂这两方面的研究进展状况进行综述.     

基于赝复体指导的义耳种植术前设计与修复

目的:探讨以赝复体为指导的义耳种植术前设计与修复.方法:采用螺旋CT对1名右侧先天性小耳畸形患者进行颅颌面三维重建,Geomagic软件中行虚拟残耳切除,获得种植导板并确定赝复体的位置.利用导板定位行残耳切除术及种植体植入术,制作卡杆附着体及树脂支架.采用三维光学扫描仪进行面部的三维成像,将CT数据和三维数据拟合,获得最终义耳赝复体的三维模型数据,通过选域激光烧结技术制作义耳蜡型,并翻制成硅胶义耳.结果:最终完成的义耳赝复体与种植修复前的赝复体形态位置完全一致,组织面与缺损区表面完全贴合,其形态、高度与对侧完全一致,患者对颜色、外观非常满意.结论:基于赝复体指导的义耳种植术前设计与修复是一种行之有效的办法和理念,值得在颜面部缺损赝复治疗中推广应用.     

CAD/CAM赝复体同期修复上颌窦癌上颌骨全切除后缺损的功能评价

目的:观察和评价应用CAD/CAM的中空充填式赝复体(简称CAD/CAM赝复体)同期修复上颌窦癌上颌骨全切除缺损后患者的面容及功能恢复情况.方法:18例T3-4a N0M0上颌窦癌行上颌骨全切除患者,应用CAD/CAM赝复体同期修复缺损.术后1、3、6个月定期复查,比较患者戴与不戴CAD/CAM赝复体时以及13例更换永久性赝复体的患者术后12个月戴与不戴赝复体时,面容、语音清晰度、咀嚼、吞咽情况.采用SPSS 13.0软件包对数据进行统计学处理.结果:18例患者术后1、3、6个月戴与不戴CAD/CAM赝复体比较,语音清晰度(t值分别为29.38、136.24),面部凹陷度(t值分别为2.73、4.74和5.92),眼球下坠(t值分别为8.20、15.17和14.74)均有显著差异(P＜0.05).吞咽功能由Ⅳ级到Ⅱ级,提高结果为显效.咀嚼问卷平均23分,能咀嚼硬性和一般食物.13例术后6个月更换永久性赝复体的患者,语音更清晰(t值为102.34,P＜0.05).结论:上颌窦癌上颌骨全切除术后,应用CAD/CAM赝复体修复缺损,面容及功能恢复良好,患者生活质量明显提高;可直接观察上颌骨区域的术腔变化,便于肿瘤复发的及时发现和处理,是上颌窦癌患者上颌骨全切除后同期修复缺损及重建功能的首选方案之一.     

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。     

颜面赝复体阴模三维打印成形的初步研究

目的 探讨三维打印在颜面赝复体阴模自动化加工中的可行性.方法 选取鼻数据库中鼻数字化模型1个,利用Magics RP软件生成立体成型格式的鼻阴模.通过三维打印加工鼻石膏模型和鼻阴模石膏模型.将硅橡胶充填于鼻阴模石膏模型中,获得鼻硅橡胶模型.采用结构光三维测量系统扫描鼻石膏模型和硅橡胶模型,进行偏差分析.结果 鼻石膏模型和硅橡胶模型的最大正偏差为0. 98 m,位于鼻尖;最大负偏差为-0. 64 mm,位于鼻小柱;均值为0.17 mm.结论 颜面赝复体阴模直接快速成形具有可行性.     

Fabrication of a Maxillofacial Prosthesis Using a Computer-Aided Design and Manufacturing System

PURPOSE: Maxillofacial prostheses are usually fabricated on the basis of impressions made with dental-impression material. The extent to which the prosthesis reproduces normal facial morphology depends on the clinical judgment of the individual fabricating the prosthesis. This paper describes a computer-aided design and manufacturing (CAD/CAM) system for the fabrication of maxillofacial prostheses. This system will provide a more consistently accurate reproduction of facial morphology. MATERIALS AND METHODS: Facial measurements were taken using a non-contact three-dimensional laser morphological measurement system. The measurements were sent to a computer numerical controlled (CNC) milling machine to generate a cast of the patient's face for the fabrication of prosthesis. RESULTS: Facial contours were measured using a laser. This method minimizes patient discomfort and avoids soft tissue distortion by impression material. Moreover, the digital data obtained is easy to store and transmit, and mirror-images can be readily generated by computer processing. CONCLUSION: This method offers an objective, quantified approach for fabricating maxillofacial prostheses.     

Computer-aided design of facial prostheses by means of 3D-data acquisition and following symmetry analysis

The aim of this study was to investigate whether a method of designing digital models of facial prostheses was suitable for patients with orbital defects. 32 patients were included in a retrospective study. 23 of them already had a facial prosthesis. 3D-data of the faces were acquired optically using fringe projection technique without and with (if available) the facial prosthesis in place. The healthy side of the surface models was mirrored to reconstruct the defect area. By generating a NURBS-model, the edges of the virtual prostheses were adapted to the defect region. The CAD models were stored in STL format as templates for facial prostheses. Using an automatically calculated asymmetry index (AI), four situations of the digitized facial surface were analysed for symmetry: 1. with defect area excluded, 2. with mirrored healthy surface, 3. with digital CAD template, and 4. with manually produced facial prosthesis inserted (if available). Mean AI values were 6.05 ± 3.26 (situation 1), 4.79 ± 2.51 (situation 2), 5.12 ± 2.61 (situation), and 6.74 ± 2.77 (situation 4). Additionally, the CAD templates were rated by three anaplastologists. Ratings did not differ significantly. They partially agreed with the three statements “The CAD prosthesis fits harmoniously within the face”, “The CAD prosthesis could be used for a wax pattern during conventional fabrication” and “The CAD prosthesis and the wax pattern reduce workload”. The results indicate that the presented technique has the potential to increase facial symmetry and facilitate the technical procedure. However, symmetry alone is not a sufficient criterion for design of a facial prosthesis.     

Integration of laser surface digitizing with CAD/CAM techniques for developing facial prostheses. Part 1: Design and fabrication of prosthesis replicas

PURPOSE: This article presents a novel manufacturing approach that integrates laser surface digitizing/scanning and computer-aided design (CAD) and manufacturing (CAM) to achieve automated fabrication of spatially and anatomically accurate extraoral facial prostheses. MATERIALS AND METHODS: Topologic data of the patient's face, including the site of deformity and the anatomy of a healthy "donor" organ, were acquired using laser surface digitizing. Two different CAD data manipulation techniques were developed to alleviate problems encountered in laser-digitized data sets. To reduce patient involvement, fitting of the prosthesis was conducted using a computer model of the patient's face. Once finalized, rapid prototyping techniques were employed to fabricate a master pattern to cast the final prosthesis. RESULTS: Three case studies involving different facial prostheses were conducted to evaluate the integrated manufacturing system. The results demonstrated the many advantages of the system for facial prosthesis production. CONCLUSION: With the new manufacturing approach, reduced patient discomfort, minimal dependence on the artistic skills of the prosthetist, and short turnaround times for prosthesis production can be expected.     

Integration of laser surface digitizing with CAD/CAM techniques for developing facial prostheses. Part 2: Development of molding techniques for casting prosthetic parts

PURPOSE: This article presents a novel manufacturing approach that integrates laser surface digitizing/scanning and computer-aided design and manufacturing (CAD/CAM) to achieve automated fabrication of spatially and anatomically accurate extraoral facial prostheses. MATERIALS AND METHODS: Contrary to the approach in part 1 for fabricating positive replicas of prostheses, the approaches presented here are focused on designing and producing negative molds of the final prostheses using CAD, rapid prototyping, and rapid tooling techniques. The molds were applied directly to cast the final prostheses, thereby eliminating conventional flasking and investing procedures. RESULTS: Three different facial prostheses were produced to evaluate the proposed approach for prosthesis production. The advantages of this alternative manufacturing approach over the approach presented in part 1 and conventional techniques are discussed. The limitations encountered with the integrated manufacturing system are highlighted. CONCLUSION: With the new techniques, reduced patient discomfort, minimal dependence on the artistic skills of the prosthetist, and short turnaround times for prosthesis production can be expected.     

Digital imaging in the fabrication of ocular prostheses

Several ocular and orbital disorders require surgical intervention that may result in ocular defects. The associated psychological effect of these defects on the patient requires immediate management and rehabilitation intervention by a team of specialists. The role of the maxillofacial prosthodontist in fabricating an ocular prosthesis with acceptable esthetics to restore facial symmetry and normal appearance for the anophthalmic patient becomes essential. This article presents a technique for fabricating ocular prostheses using the advantages of digital photography.     

Reconstruction of the temporomandibular joint: a comparison between prefabricated and customized alloplastic prosthetic total joint systems

The implantation of an alloplastic total temporomandibular joint (TMJ) prosthesis is an innovative approach for the treatment of end-stage TMJ disorders. Two types of system exist: prefabricated (stock) and customized computer-aided design/computer-aided manufacturing (CAD/CAM) devices. A clinical study was performed to evaluate the effectiveness of these two designs. Twenty-eight patients treated between 2015 and 2017 were included and assigned to two groups: stock prostheses (group 1) and customized CAD/CAM prostheses (group 2). Clinical evaluations were performed at five time-points up to 6 months postoperative. Parameters included maximum interincisal opening, pain, diet, complications, and subjective well-being at the end of follow-up. Differences between pre-surgery and 6-month post-surgery values were highly significant (P < 0.001). No patient required a liquid diet at the end of treatment, and 66% of group 1 patients and 100% of group 2 patients reported improved well-being. Complications were observed in 32% of patients and included temporary paralysis of the facial nerve. In conclusion, clinical outcomes of stock and CAD/CAM prostheses suggested great improvements in mouth opening and reduction of pain as a result of the rehabilitation of TMJ function. Results showed comparable data for the two types of prosthesis design at 6 months postoperative.     

Direct 3D Printing of Flexible Nasal Prosthesis: Optimized Digital Workflow from Scan to Fit

A maxillofacial prosthesis is a successful treatment modality to restore missing facial parts. Digital technologies and 3D printing are employed in constructing facial prostheses such as ears; however, their application is still partial, and final prostheses are usually manufactured conventionally using stone molds. This report aims to introduce a complete digital workflow to construct a nasal prosthesis and compare it to the conventional workflow of a patient requiring a nasal prosthesis. A computer tomography scan showing the defect was exported to specialized software to create 3D reconstructions of the patient's face and underlying bone. The nose was digitally designed restoring facial esthetics, anatomy, shape, and skin color. Different skin tones were digitally matched to skin tissues adjacent to the defect area using the Spectromatch system. The design was 3D printed in flexible and colorful material at 16 μm resolution using a 3D printer. External color pigmentations were applied to the nose for optimum esthetics, and the prosthetic nose was sealed in silicone and left to heat polymerize for 15 minutes. The prosthetic nose was retained in place using biomedical adhesive, and the patient was pleased with it. This report proposes a complete digital workflow to directly design and fabricate a prosthetic nose of acceptable esthetics. Such a workflow can lead to enhanced prosthesis reproducibility and acceptability and may become an effective treatment option for treatment of patients with facial defects.     

Computer-assisted technique for the design and manufacture of realistic facial prostheses

We describe a technique for the design and fabrication of realistic facial prostheses using three-dimensional optical imaging and computer-aided design and manufacturing (CAD/CAM). A three-dimensional dataset of the facial surface of a patient who needed a facial prosthesis was obtained using a sensing system, and the three-dimensional image of the face was reconstructed. A decreased and thinned virtual prosthesis was designed based on the facial image and converted into a rapid prototyping wax prosthesis using a selective laser sintering technique. The rapid prototyping wax prosthesis was then dipped into melted base-plate wax which generated a layer of wax on the internal and external surfaces to record its size and thickness. The modified prosthesis was evaluated and refined, and processed to generate a realistic silicone prosthesis. Three-dimensional data acquisition using the sensing system and computer-assisted design and manufacture of the prosthesis allows us to see a whole face without damaging the soft tissues or causing discomfort to the patient or exposure to radiation. The final prosthesis was of satisfactory size, shape, and cosmetic appearance, matched the malformed area, and suited the patient's requirements.     

Simulation of tissue-prosthesis margin interface by using surface scanning and digital design for auricular prostheses

Statement of problemOne of the most challenging aspects of auricular prosthesis design and fabrication is ensuring that the prosthesis fits the patient through a range of head and facial movements. Techniques used in conventional prosthetic treatment pathways account for issues of prosthesis fit, but this challenge has not been fully addressed in emerging treatment pathways that use digital technology.PurposeThe purpose of this clinical study was to develop and evaluate a digital workflow by using surface scan data and incorporating the simulation of tissue movement into the design of auricular prostheses that fit the participant through a range of facial movements. An iterative design process was used to develop a design workflow through a sequential case series of participants with auricular prostheses.Material and methodsScan data were acquired from a case series of 5 participants with existing implant-retained auricular prostheses. An iterative design process was used to digitally design auricular prostheses that fit the participants through a range of jaw and facial movements. The fit, shape, and retention of the digitally designed and conventionally made prostheses were assessed and compared. Design considerations were identified and documented through the iterative design process.ResultsA final design workflow was iteratively developed based on the 5 participants. The shapes of the digitally designed prostheses were well matched to nontreatment anatomy overall. Prosthesis fit was variable: Some digitally designed prostheses fit the participant intimately through a range of movements, and others experienced significant gaps between the margins and the tissues.ConclusionsAn iterative design process provided a method of working toward quality improvement. Although the final design workflow provides a generally successful method of manipulating scan data in the design of auricular prostheses, the prosthesis fit at the anterior margin during facial movements remains variable and requires further development to achieve a consistently acceptable solution.