earticle

영어

Purpose: This in vitro study evaluated changes in the fit accuracy and surface roughness of selective laser melting (SLM)-fabricated substructures following three postprocessing protocols: no treatment (NT), heat treatment (HT), and heat+pressure treatment (HPT). Methods: For all specimens, an identical abutment model of the maxillary right first molar was used. Thirty single copings and flat plate specimens were fabricated using the SLM technique with a Co–Cr alloy and divided into three groups (n=10 each) according to postprocessing: NT, HT, and HPT. Marginal and internal fit were assessed using the silicone replica technique with two-dimensional analysis, and surface roughness was measured under ×200 magnification with a microscope. One-way ANOVA was performed, followed by Tukey’s HSD and Scheffé’s post hoc tests (α=0.05). Results: Marginal and internal fit differed significantly between the NT group and the postprocessed groups (HT and HPT), demonstrating the effect of postprocessing. No significant difference was observed between the HT and HPT groups. Regarding surface roughness, the HPT group exhibited the lowest values, although the HT and HPT groups were statistically similar. Conclusion: Postprocessing enhances the fit and surface characteristics of SLM-fabricated Co–Cr restorations. Therefore, postprocessing is recommended as an essential step to ensure the long-term clinical performance of SLM-based prostheses.