2026 Volume 24 Issue 3 Pages 136-147
The mechanical properties of stereolithography (SLA)-printed materials are influenced by printing parameters. This study examined the effects of printing orientation and layer thickness on the surface and flexural mechanical properties of two chemically distinct SLA resins. Specimens were fabricated from two photopolymer resins: Model Resin V3 (MR) and Surgical Guide Resin V1 (SR) which are identified as methacrylate-based photopolymers. For each resin, specimens were printed at two layer thicknesses (50 and 100 μm) and in five printing orientations. Dynamic micro-indentation and three-point bending tests were performed to evaluate surface and flexural mechanical properties. Printing orientation was the most influential factor governing flexural properties, and the 0-I orientation consistently produced the lowest values for both resins. A smaller layer thickness (50 μm) generally improved mechanical properties, with a more pronounced effect in SR than in MR. Resin type showed a combined influence with the fabrication parameters; the relative performance of the two resins varied according to printing orientation. The mechanical properties of SLA-printed components are highly sensitive to printing parameters, particularly printing orientation. The 0-I orientation should be avoided when high flexural performance is required. Although a smaller layer thickness is generally advantageous, the results suggest a combined impact of material selection and fabrication parameters. Optimal fabrication therefore requires coordinated consideration of resin type, printing orientation, and layer thickness.
