Sun Yuchun, Chen Hu, Li Hong, Deng Kehui, Zhao Tian, Wang Yong, Zhou Yongsheng
Center of Digital Dentistry, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing, 100081, People's Republic of China.
National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing, China.
Sci Rep. 2017 Nov 2;7(1):14958. doi: 10.1038/s41598-017-14005-8.
This study aimed to evaluate the quality of the final impressions taken by three-dimensional printed custom trays for edentulous patients. Custom trays were designed with or without saddle-shaped tissue stops and fabricated by three-dimensional printing techniques. Manually made trays with photocurable materials were produced as controls. Both 3D printed custom trays and manually made ones were used to take impressions from edentulous patients. After 3D scanning of the final impression, the impression materials were removed, thus the underneath tray surfaces were able to be scanned, allowing the thickness of the impression materials to be measured. Final impressions obtained by pre-border-molded 3D printed trays were scanned as references, to which the flange extension deviations and morphology deviations of the impressions taken by both 3D printed trays and manually made ones were calculated. The results showed that (1) impressions from 3D printed custom trays had better thickness distribution than that of manually made ones; (2) impression morphology deviations in non-marginal area were neither statistic different between 3D printed trays and manually made trays, nor between trays with and without tissue stops; and (3) final impressions taken by custom trays without pre-border-molding were tended to have insufficient flange extensions.
本研究旨在评估三维打印定制托盘为无牙颌患者制取的终印模的质量。定制托盘设计有或没有鞍形组织阻挡，并采用三维打印技术制作。用光固化材料制作的手工托盘作为对照。三维打印定制托盘和手工制作的托盘均用于为无牙颌患者制取印模。对终印模进行三维扫描后，去除印模材料，从而能够扫描托盘底面，测量印模材料的厚度。将预边缘成型的三维打印托盘制取的终印模进行扫描作为参考，计算三维打印托盘和手工制作托盘制取的印模的边缘延伸偏差和形态偏差。结果表明：（1）三维打印定制托盘制取的印模厚度分布比手工制作的更好；（2）三维打印托盘和手工制作托盘在非边缘区域的印模形态偏差无统计学差异，有和没有组织阻挡的托盘之间也无统计学差异；（3）未进行预边缘成型的定制托盘制取的终印模边缘延伸往往不足。
