Assessment Of The Reproducibility And Precision For Milling And 3d Printing Surgical Guides

Abstract

Objective: The aim of the present study was to evaluate the reproducibility and precision of two types of surgical guides, obtained by using 3D printing and milling methods. Methods: A virtual model was developed, which allowed the virtual design of surgical guide project that were milled (n = 10) or 3D printing (n = 10). Surgical guides were digitally oriented and overlapped on the virtual model that had generated them. For milling guides, it was used the Sirona Dentsply system, while 3D printing guides were produced at the Perfactory P4K Life Series, the EnvisionTEC's E-Guide Tint. In this way, average mismatches from the master model were determined. Moreover, coefficients of variation, root mean square deviations, and mismatches during an overlap were evaluated after obtaining individual misalignments for each guide, in order to verify the reproducibility of the guides and the precision of the methods for obtaining the guides Results: The evaluations showed that both groups presented the same degree of mismatch during overlap, with no statistically significant differences between the groups. However, the intragroup evaluation for misalignment, 3D printing surgical guides had a higher coefficient of variation than the milled guides, since a statistically significant difference was observed between groups in the RMS of the guide from the master model. Conclusions: Milling of the guides resulted in smaller misalignments from the master model.