Comparison of corrosion values of framework metals produced by different methods in various liquids

Although many new materials have been developed, metal-based restorations are still widely preferred in dental treatments. However, corrosion in these restorations can negatively affect treatment success. This study aimed to evaluate the corrosion behavior, ion release, and surface characteristics of Ti₆Al₄V and CoCr alloys produced using casting, CAD/CAM milling, and laser sintering techniques after immersion in different liquids. CoCr specimens were prepared using all three methods, while Ti₆Al₄V specimens were prepared by milling and laser sintering. Each group contained 21 specimens, totaling 105 samples. Specimens were immersed for 14 days in acidic liquids (cola and lemon juice) and neutral artificial saliva as a control. Electrochemical corrosion testing, static immersion testing, and SEM analyses were performed. Open circuit potential (OCP), corrosion rate, Icorr, Vcorr, metal ion release, and weight change were evaluated. Data were analyzed using JAMOVI software, and normality was assessed with the Shapiro-Wilk test. Parameters were analyzed using Robust ANOVA, one-way ANOVA, or Kruskal-Wallis tests as appropriate, and multiple comparisons were performed with Bonferroni and Dunn tests (α = 0.05). Results showed significant differences depending on liquid type, fabrication method, and material (p<0.05). The highest corrosion values were observed in cola, while the lowest values occurred in artificial saliva. Laser sintering exhibited higher corrosion and ion release compared to milling (p<0.001). Ti₆Al₄V showed greater corrosion rate, ion release, and weight loss than CoCr. Notably, titanium demonstrated a markedly higher corrosion tendency in acidic environments.