Find in Library

This study aimed to compare the surface roughness, hardness, and flexure strength of interim indirect resin restorations fabricated with CAD-CAM (CC), 3D printing (3D), and conventional techniques (CV). Twenty disk (3 mm × Ø10 mm) and ten bar specimens (25 × 2 × 2 mm) were fabricated for the CC, 3D, and CV groups, to be used for surface roughness, micro-hardness, and flexural strength testing using standardized protocol. Three indentations for Vickers micro-hardness (VHN) were performed on each disk and an average was identified for each specimen. Surface micro-roughness (Ra) was calculated in micrometers (μm) using a 3D optical non-contact surface microscope. A three-point bending test with a universal testing machine was utilized for assessing flexural strength. The load was applied at a crosshead speed of 3 mm/min over a distance of 25 mm until fracture. Means and standard deviations were compared using ANOVA and post hoc Tukey–Kramer tests, and a <i>p</i>-value of ≤0.05 was considered statistically significant. Ra was significantly different among the study groups (<i>p</i> < 0.05). Surface roughness among the CC and CV groups was statistically comparable (<i>p</i> > 0.05). However, 3D showed significantly higher Ra compared to CC and CV samples (<i>p</i> < 0.05). Micro-hardness was significantly higher in 3D samples (<i>p</i> < 0.05) compared to CC and CV specimens. In addition, CC and CV showed comparable micro-hardness (<i>p</i> > 0.05). A significant difference in flexural strength was observed among the study groups (<i>p</i> < 0.05). CC and 3D showed comparable strength outcomes (<i>p</i> > 0.05), although CV specimens showed significantly lower (<i>p</i> < 0.05) strength compared to CC and 3D samples. The 3D-printed provisional restorative resins showed flexural strength and micro-hardness comparable to CAD-CAM fabricated specimens, and surface micro-roughness for printed specimens was considerably higher compared to CAD-CAM and conventional fabrication techniques.