earticle

영어

Purpose: This study aimed to compare the effect of the fabrication method of cobalt-chromium (Co-Cr) removable denture metal frameworks on the bond strength with denture base resin. Methods: Specimens were divided into two groups based on the fabrication method: the conventional casting method group (CS) and the digital computer-aided design/computeraided manufacturing (CAD/CAM) milling method group (MS). Each metal specimen was treated with a heat-polymerized denture base resin following the standard clinical procedures for removable prosthesis fabrication. To minimize variability, all specimens underwent uniform surface polishing. Shear bond strength was measured using a universal testing machine at a crosshead speed of 1.0 mm/min. Fracture surfaces were subsequently analyzed by scanning electron microscopy (SEM). Data analysis was conducted with IBM SPSS Statistics version 24.0 (IBM), with a statistical significance level set at 0.05, and independent samples t-test was applied. Results: The MS group exhibited significantly higher shear bond strength than the CS group (p<0.05). SEM analysis revealed that both groups predominantly exhibited cohesive and mixed failure modes, with a notable prevalence of cohesive fractures. Conclusion: Both fabrication methods achieved clinically acceptable bond strength between the Co-Cr framework and the denture base resin. The milled Co-Cr specimens exhibited superior bonding strength, indicating that the CAD/CAM milling technique may be a viable alternative to conventional casting for the fabrication of removable prosthesis frameworks. However, further research is needed to confirm the results.