*Article* **Comparison of Marginal Integrity and Surface Roughness of Selective Laser Melting, CAD-CAM and Digital Light Processing Manufactured Co-Cr Alloy Copings**

**Abdulaziz S. Alqahtani 1, Abdullah M. AlFadda 2, Malek Eldesouky 2, Mazen K. Alnuwaiser 2, Samar Al-Saleh 1, Saad Alresayes 1, Abdullah Alshahrani 1, Fahim Vohra <sup>1</sup> and Tariq Abduljabbar 1,\***


**Abstract:** The purpose of the present study was to evaluate the influence of fabrication techniques on the surface micro-roughness (Ra) and marginal misfit of cobalt chromium (CoCr) copings. A mandibular first molar was prepared for a metal ceramic crown. Forty metal copings were prepared and divided into groups (n = 10). Group 1, Casting-Lost wax technique (Cast-LWT), Group 2, CAD-CAM, Group 3, Selective laser melting (SLM), and Group 4, Digital light processing-Cast (DLP-Cast). Ra was measured using laser profilometry and marginal misfit was analyzed with Micro-CT. Analysis of variance (ANOVA), Tukey multiple comparison, and correlation coefficient tests were applied (*p* < 0.05). SLM technique showed the highest Ra (2.251 ± 0.310 μm) and the Cast-LWT group presented the lowest Ra (1.055 ± 0.184 μm). CAD-CAM copings showed statistically lower Ra compared with SLM samples (*p* = 0.028), but comparable Ra to DLP-Cast (*p* > 0.05). CoCr copings fabricated from the DLP-Cast technique demonstrated the highest marginal misfit (147.746 ± 30.306 μm) and the lowest misfit was established by SLM copings (27.193 ± 8.519 μm). The SLM technique displayed lower marginal misfit than DLP-Cast and CAD-CAM (*p* = 0.001), but comparable misfit to Cast-LWT copings. Ra influenced the marginal misfit in CAD-CAM, SLM, and DLP-Cast technique-fabricated copings. (*p* < 0.01). Marginal misfit and Ra of CoCr copings are contingent on the different fabrication techniques.

**Keywords:** marginal misfit; laser profilometry; Micro-CT; selective laser melting; CAD-CAM
