Steps for biomodel acquisition through addtive manufacturing for health

ABSTRACT The use of rapid prototyping in medical and dental fields consists of three-dimensional models using Computer Aided Design systems and Computer Aided Manufacturing systems. Such systems focus specifically on enhanced 3D visualization tools that provide a precise preoperative planning opportunity through three-dimensional printing, to the professional. The objective of this study was to describe the main steps in the biomodel manufacturing using an Objet 3D printer (CONNEX 350), whose raw material is a light-curing resin. The steps are adopted by researchers from three-dimensional technologies laboratory (LT3D), of the Center for Strategic Technologies in Health (NUTES), from the State University of Paraíba (UEPB), Brazil. It begins with the acquisition of tomographic images that are processed through specific software and exported to the digital Stereo lithography (STL) format. The additive manufacturing technique is Stereo lithography, which consists in the construction of biomodel by photopolymerization of a liquid epoxy resin using ultraviolet radiation. The biomodel that comes from this process was brought to a pressurizing machine to remove the resin support, washing it with water jets. After this step, this biomodel was sent to the health professional in charge. The use of biomodels constitutes a major breakthrough in the area of Dentistry, allowing more precise diagnosis by professionals, simulation and surgical planning, previous adaptation of biomaterials and orthoses, as well as interaction between the surgeon and the patient, thus obtaining more satisfactory aesthetic results and decreased surgical time.

摘要 快速原型技术在医疗与牙科领域的应用，依托计算机辅助设计（Computer Aided Design, CAD）系统与计算机辅助制造（Computer Aided Manufacturing, CAM）系统构建三维模型。此类系统搭载增强型三维可视化工具，可协助专业人员通过三维打印实现精准的术前规划。本研究旨在描述使用Objet 3D打印机（CONNEX 350型号）制备生物模型的主要步骤，该设备以光固化树脂（light-curing resin）为原材料，相关流程由巴西帕拉伊巴州立大学（UEPB）健康战略技术中心（NUTES）下属三维技术实验室（LT3D）的研究人员制定并采用。流程始于断层扫描图像的采集，经专用软件处理后导出为立体光刻（Stereo lithography, STL）数字格式文件。本次采用的增材制造技术为立体光刻技术，其原理为利用紫外线辐射使液态环氧树脂发生光聚合反应，以此逐层构建生物模型。经该流程制备得到的生物模型将被送入加压设备，通过高压水流冲洗以去除树脂支撑结构。完成上述步骤后，该生物模型将被送至负责的医疗专业人员手中。生物模型的应用是牙科医学领域的重大突破，可助力专业人员实现更精准的诊断、手术模拟与规划，提前适配生物材料与矫形器，同时便于外科医生与患者开展沟通交流，最终获得更理想的美学效果并缩短手术时长。