PSI - Issue 51

Mohammad Reza Khosravani et al. / Procedia Structural Integrity 51 (2023) 81–87 Mohammad Reza Khosravani et al. / Procedia Structural Integrity 00 (2022) 000–000

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specimens the crack propagation was started from the root of the pre-crack, growing straight vertically in the + Y direction.

4. Concluding remarks

The digital construction of dental restorations can be achieved feasibly by di ff erent routes, either through the sub tractive or additive manufacture approach. 3D printing has significantly contributed to improve dental care outcomes. Indeed, 3D printing is very practical in terms of a complex modeling, where the layer-by-layer build-up can print internal hollowed and microscopic structures precisely. Currently, SLA shows more promise than other 3D print ing techniques, because it can be used to build crown frameworks that meet dental standards. This paper aimed to study fracture behavior of 3D-printed dental resin. To this end, dumbbell-shaped and SENB specimens were designed in CAD platform and then saved as ‘.stl’ format. All specimens were printed using Formlabs Form 2 SLA printer. Later, tensile tests and three-point bending tests were performed on the fabricated specimens. All tests were con ducted at room temperature under static loading conditions. Based on the examined specimens, stress-strain relation of dumbbell-shaped specimens are determined. Experimental practices showed that the load increased linearly, then reached a peak and then decreased in a stable fashion. The load decrease corresponds to the crack propagation. Here, a 3D laser microscope and a free-angle observation system were used to analyze the fracture growth trajectories of the SENB specimens. The visual investigation confirmed that that the fracture trajectory in the SENB specimen is straight and along the initial crack. The obtained results indicate mechanical and fracture behavior of 3D-printed dental resin which are currently used for fabrication of surgical guides. The wide application of 3D printing in dentistry implies the further investigation about SLA dental resins.

Acknowledgements

This work as part of the project “Smart Production Design Center” (SmaP) is funded by the European Regional Development Fund (ERDF) under the program OP EFRE NRW 2014-2020 ( EFRE - 0200545 ).

References

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