Banjar Ayman, Chen Yo-Wei, Kostagianni Aikaterini, Finkelman Matthew, Papathanasiou Aikaterini, Chochlidakis Konstantinos, Papaspyridakos Panos
Department of Restorative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
Department of Prosthodontics, Tufts University School of Dental Medicine, Boston, MA.
J Prosthodont. 2021 Dec;30(9):783-788. doi: 10.1111/jopr.13335. Epub 2021 Feb 3.
To conduct an in vitro comparison of the amount of three-dimensional (3D) deviation of 3D printed casts generated from digital implant impressions with an intraoral scanner (IOS) to stone casts made of conventional impressions.
A maxillary master cast with partially edentulous anterior area was fabricated with two internal connection implants (Regular CrossFit, Straumann). Stone casts (n = 10) that served as a control were fabricated with the splinted open-tray impression technique. Twenty digital impressions were made using a white light IOS (TRIOS, 3shape) and the Standard Tesselation Language (STL) files obtained were saved. Based on the STL files, a digital light processing (DLP) and a stereolithographic (SLA) 3D printer (Varseo S and Form 2) were used to print casts (n = 10 from each 3D printer). The master cast and all casts generated from each group were digitized using the same IOS. The STL files obtained were superimposed on the master cast STL file (reference) to evaluate the amount of 3D deviation with inspection software using the root mean square value (RMS). The independent-samples Kruskal-Wallis test and Dunn's test with Bonferroni correction (for post hoc comparisons) were used for statistical analyses.
The Varseo S group had the lowest median RMS value [77.5 µm (IQR = 91.4-135.4)], followed closely by the Conventional group [77.7 µm (IQR = 61.5-93.4)]. The Form 2 had the highest mean value [98.8 µm (IQR = 57.6-87.9)]. The independent-samples Kruskal-Wallis test revealed a significant difference between the groups (p = 0.018). Post hoc testing revealed a significant difference between Varseo S and Form 2 (p = 0.009).
The casts generated from the Varseo S 3D printer had better 3D accuracy than did those from the Form 2 3D printer. Both the Varseo S group and the conventional stone casts groups had similar 3D accuracy.
对通过口腔内扫描仪（IOS）获取的数字种植体印模所生成的3D打印模型与传统印模制作的石膏模型的三维（3D）偏差量进行体外比较。
制作一个上颌主模型，前部区域部分无牙，植入两颗内连接种植体（Regular CrossFit，士卓曼）。采用夹板式开放托盘印模技术制作10个作为对照的石膏模型。使用白光IOS（TRIOS，3shape）获取20个数字印模，并保存得到的标准三角测量语言（STL）文件。基于这些STL文件，使用数字光处理（DLP）和立体光刻（SLA）3D打印机（Varseo S和Form 2）打印模型（每个3D打印机打印10个）。使用同一台IOS对上颌主模型和每组生成的所有模型进行数字化处理。将获得的STL文件与上颌主模型STL文件（参考文件）叠加，使用检查软件通过均方根值（RMS）评估3D偏差量。采用独立样本Kruskal-Wallis检验和经Bonferroni校正的Dunn检验（用于事后比较）进行统计分析。
Varseo S组的RMS值中位数最低[77.5 µm（四分位间距IQR = 91.4 - 135.4）]，紧随其后的是传统组[77.7 µm（IQR = 61.5 - 93.4）]。Form 2组的平均值最高[98.8 µm（IQR = 57.6 - 87.9）]。独立样本Kruskal-Wallis检验显示各组之间存在显著差异（p = 0.018）。事后检验显示Varseo S组和Form 2组之间存在显著差异（p = 0.009）。
Varseo S 3D打印机生成的模型比Form 2 3D打印机生成的模型具有更好的3D精度。Varseo S组和传统石膏模型组的3D精度相似。
