Open Collections

Eić, Marijana

University of British Columbia

Objective: To evaluate the effects of print orientation, post-curing time, and aging on the mechanical properties and the degree of conversion of a 3D printed resin composite (RC) indicated for permanent dental restorations. Methods: A commercially available 3D-printed RC indicated for permanent restorations (Crown, SprintRay) was selected for this study. Three-point bending was used to determine flexural strength and flexural modulus; the notchless triangular prism specimen test was used to determine fracture toughness; IR spectroscopy was used to determine degree of conversion. Samples for the tests were printed at two orientations, 0 degrees and 90 degrees, and were post-cured for 20 min, 40 min, and 60 min. The samples were stored in water and tested after 24 h. The group with the best results (0 degrees, 60 min) was also tested after 90 d of water storage. Univariate ANOVA followed by Tukey post-hoc multiple-means comparison was used to analyze the results. Results: All groups showed significantly higher flexural strength, flexural modulus, and fracture toughness with at least 40 min of post-curing time. The 0 degree/60 min group had the highest mean values for all tested mechanical properties. The flexural strength and fracture toughness were reduced after 90 d of water storage, whereas flexural modulus increased. Fracture toughness was significantly higher with a print orientation of 0 degrees compared to 90 degrees, regardless of post-curing time. The degree of conversion was not significantly impacted by the different post-curing times. Conclusion: Within the limitations of this study, variations in print orientation, post-curing time, and aging did affect the mechanical properties of the tested 3D printed resin indicated for permanent restorations. However, post-curing time did not affect the degree of conversion. The best results were obtained with a post-curing time of at least 40 min and a print orientation of 0 degrees in relation to the print platform.

Text

2024-05-03

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/88176

Craniofacial Science

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/