Subburaj K, Nair C, Rajesh S, Meshram S M, Ravi B
Department of Mechanical Engineering, Indian Institute of Technology, Powai, Mumbai, India.
Int J Oral Maxillofac Surg. 2007 Oct;36(10):938-43. doi: 10.1016/j.ijom.2007.07.013. Epub 2007 Sep 5.
External ear defects can be corrected by surgery, but this may not be feasible for personal or medical reasons. Reconstructive solutions are a good alternative, but rely on the artistry and availability of the anaplastologist. A semi-automated methodology using computer-aided design (CAD) and rapid prototyping (RP) technologies was developed for auricular prosthesis development, and demonstrated in a real-life case. The correct geometry and position of the prosthesis were ensured by stacking the computed tomography scan images of the contralateral normal ear in reverse order, and joining them using a medical modelling software program. The CAD model of the remnant portion of the defective ear was subtracted from the model of the mirrored contralateral ear, using a haptic CAD system, to obtain the final geometry of the prosthesis. Polymer models were fabricated in RP systems, and used for making a corresponding mould. Medical grade silicone rubber of the appropriate colour was packed into the mould to fabricate the final ear prosthesis and fitted to the deficient side of the patient using medical grade adhesive. The computer-aided methodology gave a high level of accuracy in terms of shape, size and position of the prosthesis, and a significantly shorter lead time compared to the conventional (manual) technique.
外耳缺损可以通过手术矫正，但出于个人或医学原因，这可能并不可行。重建解决方案是一个很好的选择，但依赖于整形修复师的技术水平和可获得性。一种使用计算机辅助设计（CAD）和快速成型（RP）技术的半自动方法被开发用于耳廓假体的研制，并在一个实际案例中得到了验证。通过将对侧正常耳朵的计算机断层扫描图像按相反顺序堆叠，并使用医学建模软件程序将它们拼接在一起，确保了假体的正确几何形状和位置。使用触觉CAD系统从镜像对侧耳朵模型中减去缺损耳朵残余部分的CAD模型，以获得假体的最终几何形状。在RP系统中制作聚合物模型，并用于制作相应的模具。将适当颜色的医用级硅橡胶填充到模具中，以制造最终的耳朵假体，并使用医用级粘合剂将其安装到患者的缺损侧。与传统（手动）技术相比，计算机辅助方法在假体的形状、尺寸和位置方面具有很高的精度，并且显著缩短了交付时间。
