IADR Abstract Archives
Accuracy Assessment Protocol of Direct Metal Laser Sintering in Prosthodontics
Objectives: Direct metal laser sintering (DMLS) shows many advantages in the production of metal-based restorations, such as automation, production speed and minimal amount of waste. However, with multistage production process there is a need to define the source of possible errors. The aim of this study was to develop a standardized protocol which allows reliable and simple accuracy assessment of DMLS production procedure after each production batch for dental applications.
Methods: A standardized control model was designed in CAD software according to selected values that mimic the dental arch geometry, while a master model was designed as a construction in which the control model fits on the "key-lock" principle. Both models were 3D printed from atomized Co-Cr alloy powder using the EOS M100 (EOS GmbH, Krailling, Germany) 3D printer, after which they were precisely measured in raw form using the ATOS Q (GOM GmbH, Braunschweig, Germany) digitizer. After removing the supporting pins and polishing, a second measurement was carried out. There were 133 designated measurement reference points, grouped from A to I. Measurement data of both models in raw and finalized form was statistically analyzed using the SPSS software.
Results: Measurements of the reference points demonstrated deviations from the CAD model values. The statistically significant difference was determined in dimensional comparison of the raw and polished models (t=3.128, p=0.061). However, no statistically significant difference was determined between the CAD model and the dimensions of the polished model (t=2.492, p=0.014).
Conclusions: The results suggest that DMLS can cause dimensional discrepancies between virtual and 3D printed shapes, but they can be recognized and assessed. The developed protocol can be used to define if an error occurred in the production process.
Methods: A standardized control model was designed in CAD software according to selected values that mimic the dental arch geometry, while a master model was designed as a construction in which the control model fits on the "key-lock" principle. Both models were 3D printed from atomized Co-Cr alloy powder using the EOS M100 (EOS GmbH, Krailling, Germany) 3D printer, after which they were precisely measured in raw form using the ATOS Q (GOM GmbH, Braunschweig, Germany) digitizer. After removing the supporting pins and polishing, a second measurement was carried out. There were 133 designated measurement reference points, grouped from A to I. Measurement data of both models in raw and finalized form was statistically analyzed using the SPSS software.
Results: Measurements of the reference points demonstrated deviations from the CAD model values. The statistically significant difference was determined in dimensional comparison of the raw and polished models (t=3.128, p=0.061). However, no statistically significant difference was determined between the CAD model and the dimensions of the polished model (t=2.492, p=0.014).
Conclusions: The results suggest that DMLS can cause dimensional discrepancies between virtual and 3D printed shapes, but they can be recognized and assessed. The developed protocol can be used to define if an error occurred in the production process.