3D打印多孔钛个性化根形种植体的设计和制造

Design and Manufacture of 3D Printing Porous Titanium Root-Analogue Implant

目的介绍一种基于锥形束CT(Cone Beam CT,CBCT)获得牙根三维模型,利用计算机辅助设计(CAD)构建与牙根形态一致的表面多孔种植体,通过选择性激光熔融(SLM)技术进行3D打印制造表面多孔的根形种植体(Root-Analogue Implant,RAI)的方法。材料与方法使用CBCT对1位拔牙患者的头颅进行扫描,将生成的DICOM文件导入Mimics医学影像处理软件,分离牙齿和颌骨,将牙齿的三维网格保存为标准化的三角测量语言(STL)文件。将文件导入Geomagic Studio软件进行修饰,再用3-Matic Medical建模软件进行牙根表面的多孔结构设计以及牙冠部的基台设计。采用SLM技术和生物相容性钛合金(Ti6Al4V)粉末进行制造。结果设计得到的个性化根形多孔钛种植体模型,其表面多孔层厚度为0.5 mm,孔径0.5 mm,孔隙率为70%,多孔层内部为缩小的根形实心结构。3D打印制造的成品形态与设计模型一致,其颈部以下外形也与拔除的患牙一致。结论利用3D打印技术制造个性化多孔钛种植体可能成为即刻种植的一种方法,因其与牙槽窝的适合性,相比较于传统的即刻种植能够缩短治疗周期,但是否能够达到良好的骨结合尚需进一步实验验证。

Objective This paper introduces a method to obtain the three-dimensional model of tooth root based on cone beam CT(Cone Beam CT,CBCT)to construct the surface porous implant consistent with the root shape by computer-aided design(CAD),and to manufacture the root-analogue implant(RAI)by 3D printing by selective laser melting(SLM)technology.Materials and Methods The head of a patient with tooth extraction was scanned with CBCT,and the generated DICOM file was imported into Mimics medical image processing software to separate teeth and jaws,and the three-dimensional mesh of teeth was saved as a standardized triangulation language(STL)file.Import the file into Geomagic Studio software for modification,and then use 3-Matic Medical modeling software to design the porous structure of the root surface and the abutment of the crown.It was manufactured by SLM technology and biocompatible titanium alloy(Ti6Al4V)powder.Results The designed porous titanium root-analogue implant model has a surface porous layer thickness of 0.5 mm,a pore diameter of 0.5 mm,a porosity of 70%,and a reduced root solid structure inside the porous layer.The shape of the finished product produced by 3D printing is consistent with the design model,and the shape below the neck is also consistent with that of the extracted teeth.Conclusion Using 3D printing technology to make personalized porous titanium implant may be a method of immediate implantation.because of its suitability with alveolar fossa,it can shorten the treatment cycle compared with traditional immediate implantation.however,whether a good bone union can be achieved or not needs further experimental verification.