Accuracy of 3D Printed Implant Casts Versus Stone Casts: A Comparative Study in the Anterior Maxilla

Abstract

Purpose 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. Material and Methods 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. Results 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). Conclusion 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.

Accuracy Comparison among 3D-Printing Technologies to Produce Dental Models

“…Compared with conventional stone casts, 3D-printed models have been described to be equally accurate [3]. Although this could not be assessed herein, it is noteworthy that the advantages of 3D-printing over conventional methods are not limited to accuracy, but also includes faster procedures and better communication with professionals such as the dental technologist [18].…”

“…However, recent articles have described 3D-printing as clinically acceptable to produce dental devices such as crowns, surgical guides, and dental casts, with clinical results comparable to the respective milled and conventionally produced devices [1,4]. A recent article found similar accuracy results between 3D-printed models using specific technologies and conventional stone casts [3].…”

“…The layers of the object will then be successively built up on top of each other until the object is manufactured completely. This type of technology is described to lead to minimal material waste and to produce dental casts with highly detailed and clinically acceptable geometries [3].…”

“…Instead of using a laser beam to scan each layer at a time, the DLP printer projects a silhouette of the entire first layer simultaneously and cures it with light. This enables a relatively faster printing procedure, as compared to SLA [3,4].…”

Accuracy of 3D printed dental casts for protective dental splints during general anesthesia

“…Park et al evaluated the dimensional accuracy and surface characteristics of dental casts printed by various types of 3D printers (Park et al , 2020). Banjar et al compared the accuracy of casts printed by 3D printers and stone casts produced by conventional methods (Banjar et al , 2021). Greco et al evaluated the accuracy of 3D printing for quality standardization (Greco et al , 2021), and Nestler et al evaluated the dimensional accuracy (trueness and precision) of 3D printed casts (Nestler et al , 2021).…”