Abstract:

Cobalt-chromium (Co-Cr) alloys remain a fundamental material in prosthetic dentistry due to their high strength, durability, and corrosion resistance. The evolution of manufacturing technologies, including subtractive and additive methods, has introduced variations in the mechanical performance of these alloys.
Aim. This study aimed to evaluate and compare the flexural strength of Co-Cr alloys fabricated using three different techniques: conventional casting, CAD/CAM milling, and selective laser melting (SLM), using a classical three-point bending test.
Materials and Methods. Fifteen standardized specimens divided into three groups (n = 5 per group) were fabricated using casting, milling, and SLM. Flexural strength was evaluated using a three-point bending test under standardized conditions. Flexural strength test was carried out using a stand type MultiTest 2,5-i (Mecmesin Ltd, UK), calculating the force required to break the test bodies, following standard testing specifics. Statistical analysis was performed using one-way ANOVA followed by a post hoc LSD test at a significance level of p < 0.05. Results. Statistically significant differences were observed among the groups (p < 0.001). The highest flexural strength was recorded in the PRINTED group (1422 MPa), followed by the CASTED group (903 MPa), while the lowest values were found in the MILLING group (670 MPa). Significant differences were identified between all groups. Conclusion. Manufacturing technique has a significant influence on the flexural strength of Co-Cr alloys. Additive manufacturing demonstrated superior mechanical performance, followed by casting, while milling exhibited the lowest values. Keywords: Co-Cr alloys, flexural strength, casting, milling, selective laser melting