Comparative Evaluation of Surface Roughness and Hardness of 3D Printed Resins

Abstract

The effect of printing parameters on the surface characteristics of three-dimensional (3D)-printed denture base resins (DBRs) is neglected. Therefore, this study investigated the effect of printing orientation and post-curing time on the surface roughness and hardness. One conventional heat-polymerized (HP) resin and two 3D-printing resins (NextDent (ND) and ASIGA (AS)) were used to fabricate a total of 250-disc (10 × 2.5 mm) specimens. ND and AS specimens were printed with different orientations (0-, 45-, and 90-degree) and each orientation group was subjected to four post-curing times (30, 60, 90, 120 min). Printed specimens were thermo-cycled (10,000 cycles) followed by the measuring of surface roughness (Profilometer (Ra)) and hardness (a Vickers hardness (VH)). ANOVA and post hoc tests were used for data analysis (α = 0.05) at significant levels. AS and ND showed no significant changes in Ra when compared with HP (p ˃ 0.05), except the 45-degree orientation (AS/90 min and AS/120 min) significantly increased surface roughness (p ˂ 0.001). There was no significant difference in Ra with different orientations and post-curing time for both materials AS and ND (p ˃ 0.05). Compared with HP, 3D-printed DBRs showed low VH values (p ˂ 0.001). For AS, 90-degree orientation showed a significant decrease in VH at 60, 90, and 120 min when compared with 0- and 45-degree orientation (p ˂ 0.001), while ND showed no significant difference in VH with different printing orientations (p ˃ 0.05). The VH of AS and ND improved when increasing post-curing time to 120 min (p ˂ 0.001), and the printing orientations and post-curing time did not affect the Ra of 3D-printed DBRs.

Machinability study on laser-based powder bed fusion processed hypo-eutectic aluminium alloy composite (AlSi10Mg + NbC)

“…The graph is plotted between the composite's average surface roughness and printing orientation; the comparison of results is shown in Figure 3. Accordingly, the printing orientation of 0° exhibits a lower surface roughness value of 2.813 µm irrespective of the high MRR (146.43 mg/min) due to the presence of a single layer in an XY (horizontal) plane 38,39 and machined under optimized conditions, 40 while the printing orientation of 45° and 90° resulted in 4.709 µm and 3.986 µm, respectively. After machining under optimized conditions, the 45° printed composite attained a high roughness value of 4.709 µm attributed to overlapped printed layer steps between adjacent deposits.…”

Effect of Different Vat Polymerization Techniques on Mechanical and Biological Properties of 3D-Printed Denture Base

“…In contrast, the DLP and LCD with the imaging system of curing the entire layer at once had better performance in inhibiting the adherence of the C. Albicans. An existing study compares the surface roughness between two DLP techniques and the heat-polymerized material [ 35 ]. The study showed that the surface roughness did not have significant changes across the two DLP techniques when printing with different orientations and post-curing with different time periods.…”

“…Nonetheless, the current study used a different material than the mentioned study, and varied results were expected. Another similar study compared the surface roughness and hardness of a 3D-printed denture base fabricated with two different DLP machines at different orientations [ 35 ]. The results showed that the surface roughness was not affected by the different printers and orientations; however, the different DLP printers did make an impact on the surface hardness.…”

Optimization of 3D Printing Technology for Fabrication of Dental Crown Prototype Using Plastic Powder and Zirconia Materials

“…The binding of the silane coupling agent enhanced the affinity of the polymer and zirconia resin due to interfacial adhesion [ 28 ]. The selection of denture base material and resin is crucial to the denture longevity, as it is dependent on the surface characteristic and surface properties [ 29 ].…”