Heikkinen Anssi-Kalle, Lähde Sini, Rissanen Valtteri, Salmi Mika, Aarnisalo Antti A, Mäkitie Antti, Sivonen Ville, Sinkkonen Saku T
Department of Otorhinolaryngology-Head and Neck Surgery and Tauno Palva Laboratory, Head and Neck Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
Department of Mechanical Engineering, Aalto University, Espoo, Finland.
Int J Bioprint. 2023 Apr 4;9(4):727. doi: 10.18063/ijb.727. eCollection 2023.
Despite advances in prosthesis materials, operating microscopes and surgical techniques during the last 50 years, long-lasting hearing improvement remains a challenge in ossicular chain reconstruction. Failures in the reconstruction are mainly due to inadequate length or shape of the prosthesis, or defects in the surgical procedure. 3D-printed middle ear prosthesis might offer a solution to individualize treatment and obtain better results. The aim of the study was to study the possibilities and limitations of 3D-printed middle ear prostheses. Design of the 3D-printed prosthesis was inspired by a commercial titanium partial ossicular replacement prosthesis. 3D models of different lengths (1.5-3.0 mm) were created with Solidworks 2019-2021 software. The prostheses were 3D-printed with vat photopolymerization using liquid photopolymer Clear V4. Accuracy and reproducibility of 3D printing were evaluated with micro-CT imaging. The acoustical performance of the prostheses was determined in cadaver temporal bones with laser Doppler vibrometry. In this paper, we present an outline of individualized middle ear prosthesis manufacturing. 3D printing accuracy was excellent when comparing dimensions of the 3D-printed prostheses and their 3D models. Reproducibility of 3D printing was good if the diameter of the prosthesis shaft was 0.6 mm. 3D-printed partial ossicular replacement prostheses were easy to manipulate during surgery even though they were a bit stiffer and less flexible than conventional titanium prostheses. Their acoustical performance was similar to that of a commercial titanium partial ossicular replacement prosthesis. It is possible to 3D print functional individualized middle ear prostheses made of liquid photopolymer with good accuracy and reproducibility. These prostheses are currently suitable for otosurgical training. Further research is needed to explore their usability in a clinical setting. In the future, 3D printing of individualized middle ear prostheses may provide better audiological outcomes for patients.
尽管在过去50年里，假体材料、手术显微镜和手术技术都有了进步，但在听骨链重建中实现持久的听力改善仍然是一项挑战。重建失败主要是由于假体长度或形状不合适，或手术操作存在缺陷。3D打印中耳假体可能为个性化治疗提供解决方案并取得更好的效果。本研究的目的是探讨3D打印中耳假体的可能性和局限性。3D打印假体的设计灵感来自一种商用钛质部分听骨置换假体。使用Solidworks 2019 - 2021软件创建了不同长度（1.5 - 3.0毫米）的3D模型。假体采用液体光聚合物Clear V4通过光固化3D打印而成。使用微型计算机断层扫描成像评估3D打印的准确性和可重复性。通过激光多普勒振动测量法在尸体颞骨中测定假体的声学性能。在本文中，我们概述了个性化中耳假体的制造过程。比较3D打印假体及其3D模型的尺寸时，3D打印精度极佳。如果假体杆的直径为0.6毫米，3D打印的可重复性良好。尽管3D打印的部分听骨置换假体比传统钛质假体稍硬且柔韧性稍差，但在手术过程中易于操作。它们的声学性能与商用钛质部分听骨置换假体相似。使用液体光聚合物3D打印功能个性化中耳假体并具有良好的准确性和可重复性是可行的。这些假体目前适用于耳外科手术培训。需要进一步研究以探索它们在临床环境中的可用性。未来，个性化中耳假体的3D打印可能为患者提供更好的听力结果。
