Xu X X, Cao Y, Zhao Y J, Jia L, Xie Q F
Department of Prosthodontics, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China.
Center for Digital Dentistry, Peking University School and Hospital of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Beijing Key Laboratory of Digital Stomatology, Beijing 100081, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2020 Dec 18;53(1):54-61. doi: 10.19723/j.issn.1671-167X.2021.01.009.
To establish a method for the production of digital individual tooth tray based on three-dimensional (3D) scan, computer-aided design (CAD) and 3D printing, and to evaluate the effect of impression taking of full-arch crown abutments by digital individual tooth tray technique and conventional method through study.
The full crown preparation was performed on all the fourteen resin teeth in a standard model of mandibular dentition. The surface data of prepared abutments was collected by 3D scanning. A new project was created in a dental CAD software including all the fourteen teeth in the mandibular dentition. The design modules of anatomy crown and coping were selected for each tooth. The dentition was divided for three sections: right posterior teeth, anterior teeth, and left posterior teeth areas. The connector design was added between the abutments within the same section. The scanned data of the abutments were imported. The occlusal plane and insertion path were determined. The position of margin line, as well as the shape of anatomy crown and connector as the main body of the individual tooth tray were designed for each abutment. The shape of coping was generated as the space for holding the impression material. The finalized data of the main body was imported into Geomagic software. The retentive attachment was added at the external surface and the tissue stop was formed at the internal surface. The completed individual tooth tray was manufactured by 3D printing with resin material. The data of full-arch crown abutments were modified and printed. The conventional dentition trays A and B, as well as digital individual tooth tray were designed and printed for four copies each. The polyether impressions of the full-arch abutments were made by conventional one-step method using dentition tray A, and by sectional-impression technique using digital individual tooth tray and dentition tray B for four times each. The time spent for each impression taking and the numbers of defects at the shoulder and axial/occlusal surface in each impression were recorded. The impression quality of each abutment was evaluated. The overall quality distribution and the pass rate of abutments between the two methods were analyzed.
The impressions made by conventional method had more defects at shoulder than those made by digital individual tooth tray technique. No difference of the number of defects at axial/occlusal surface between the two methods was observed. The digital individual tooth tray technique for the full-arch abutment impression exhibited higher pass rate of abutments and better quality of impression, compared with conventional methods.
A new method for the production of digital individual tooth tray based on digital scanning, CAD and 3D printing was established. Compared with conventional method, using digital individual tooth tray technique for impression taking of full-arch abutments can achieve better effect.
建立一种基于三维（3D）扫描、计算机辅助设计（CAD）和3D打印制作数字化单颗牙托盘的方法，并通过研究评估数字化单颗牙托盘技术和传统方法取全牙弓冠基牙印模的效果。
在标准下颌牙列模型的14颗树脂牙上进行全冠预备。通过3D扫描收集预备后基牙的表面数据。在牙科CAD软件中创建一个新项目，包括下颌牙列的全部14颗牙齿。为每颗牙齿选择解剖冠和基底冠的设计模块。将牙列分为三个部分：右侧后牙、前牙和左侧后牙区域。在同一区域内的基牙之间添加连接体设计。导入基牙的扫描数据。确定咬合平面和就位道。为每个基牙设计边缘线位置以及作为单颗牙托盘主体的解剖冠和连接体的形状。生成基底冠的形状作为容纳印模材料的空间。将主体的最终数据导入Geomagic软件。在其外表面添加固位附件，在内表面形成组织止点。用树脂材料通过3D打印制作完成的单颗牙托盘。对全牙弓冠基牙的数据进行修改并打印。设计并打印传统牙列托盘A和B以及数字化单颗牙托盘各4份。使用牙列托盘A通过传统一步法，以及使用数字化单颗牙托盘和牙列托盘B通过分段印模技术分别对全牙弓基牙制取聚醚印模各4次。记录每次取模所用时间以及每个印模在肩台和轴面/咬合面的缺陷数量。评估每个基牙的印模质量。分析两种方法之间基牙的整体质量分布和合格率。
传统方法制取的印模在肩台处的缺陷比数字化单颗牙托盘技术制取的印模更多。两种方法在轴面/咬合面的缺陷数量上未观察到差异。与传统方法相比，全牙弓基牙印模的数字化单颗牙托盘技术表现出更高的基牙合格率和更好的印模质量。
建立了一种基于数字扫描、CAD和3D打印制作数字化单颗牙托盘的新方法。与传统方法相比，使用数字化单颗牙托盘技术取全牙弓基牙印模可取得更好的效果。
