Influence of printing orientation on mechanical properties of aged 3D-printed restorative resins

• Published in: Dental materials Vol. 40; no. 4; pp. 756 - 763
• Main Authors: Espinar, Cristina, Pérez, María M., Pulgar, Rosa, Leon-Cecilla, Alberto, López-López, Modesto T., Della Bona, Alvaro
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.04.2024
• Subjects: 3D printing resins; Composite Resins - chemistry; Dental Materials - chemistry; Dental restoration; Elastic modulus; Flexural Strength; Materials Testing; Printing orientation; Printing, Three-Dimensional; Surface Properties; Elastic modulus; Dental restoration; Printing orientation; Flexural strength; 3D printing resins
• ISSN: 0109-5641; 1879-0097
• DOI: 10.1016/j.dental.2024.02.023

To evaluate the influence of printing orientation on flexural strength (σf) and elastic modulus (E) of different 3D printing dental restorative resins. Bar-shaped specimens (n = 20) were fabricated from two SLA-printed resins (FT- Formlabs Temporary, and FP- Formlabs Permanent) and two DLP-printed resins (DFT- Detax Freeprint Temp, and GCT- GC Temporary) using two building orientations (0º and 90º). The 3D-printed structures were aged (14 d) before submitted to three-point bending in 37ºC distilled water at a crosshead speed of 1.0 ± 0.3 mm/min until fracture to calculate the σf and the E values. The fractured surfaces were evaluated using stereomicroscopy and scanning electron microscopy (SEM) following fractography principles. Data were statistically analyzed using two-way ANOVA and Tukey post-hoc (α = 0.001). FP and FT showed significantly higher E values than DFT and GCT, irrespectively of printing orientation (p < 0.001). There was no statistical difference between the building orientations (0º and 90º) for the mean σf and E values for the resin materials evaluated. Fractographic characteristics were similar for the surface fracture from all the materials evaluated, showing typical brittle fracture behavior. Printing orientation did not influence of flexural strength and elastic modulus values for the 3D-printed resin structures evaluated. Surface topography was mostly governed by the 3D printer type. •Mechanical properties such as flexural strength and elastic modulus were not affected by the printing angle.•The surface topography of the evaluated 3D-printing resins is mostly governed by the printer type.•Typical brittle fracture features were found for the evaluated 3D-printing resins.