A Comparison of the Accuracy of Two Non-dental 3D Printers and a Standard Dental 3D Printer for Printing Dental Models: An In Vitro 3D Analysis.

Background: While the majority of dentists and lab techs recommend dental-specific desktop printers, many of them use cheaper, more affordable 3D printers in their practice. The study aimed to compare the accuracy of two commercial non-dental stereolithography (SLA) 3D printers with a dental 3D printer for diagnostic dental casts.  Methods: A prototype stereolithographic (Standard Triangle/Tessellation Language (STL)) model of a dentoform was used as a master model to be printed by three 3D printers (n=10 for each printer). The casts were post-processed according to the individual manufacturer's recommendation and then scanned using a desktop dental lab scanner to produce STL files. The STL for each cast was superimposed onto the original STL master model file and dimensional discrepancies were measured.  Results: The results demonstrated a clear hierarchy in the accuracy of the 3D-printed models. The dental-specific 3D printer, Form 3B (Formlabs, Somerville, USA), produced models with the highest accuracy, exhibiting an average deviation of 37±5 µm from the original master model. Among the non-dental printers, the Mars 2 Pro (Elegoo, Shenzhen, China) showed reasonable accuracy with an average deviation of 47±22 µm, while the QiDi Tech (Qidi Technology, Zhejiang, China) had a much larger average deviation of 649±75 µm, indicating poor accuracy. Statistical analysis confirmed significant differences in mean deviations between Form 3B and QiDi Tech (t-test; p<0.01) and between Form 3B and Mars 2 Pro (t-test; p=0.05). These findings highlight the superior performance of the dental-specific 3D printer.

Conclusions: Dental-specific desktop SLA 3D printers appear to have better accuracy than non-dental desktop 3D printers. When a non-dental 3D printer is used, the accuracy of these 3D printers may or may not be sufficient for dental applications.