Evaluation of Stainless Steel Miniplates in Mandibular Fractures Using Scanning Electron Microscopy and Energy-Dispersive X-ray Analysis: A Retrospective Observational Study.

Stainless steel miniplates are widely used for mandibular fracture fixation due to their affordability and stability, yet concerns remain regarding long-term biocompatibility and corrosion-related degradation. This retrospective observational study compared the surface characteristics and elemental composition of stainless steel miniplates retrieved after 6-12 months (Group A; mean 8.4 months) and 24 months (Group B; mean 24.2 months) using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) analysis, and correlated these findings with clinical outcomes. Thirty patients were divided equally between the two groups. Clinical parameters, including pigmentation, erythema, suppuration, granulation tissue, tenderness, and plate exposure, were recorded and compared between groups. Statistical analysis was performed using the Chi-square test with phi (φ) effect sizes. Group B exhibited significantly higher corrosion (p = 0.020, φ = 0.42), surface roughness (p = 0.020, φ = 0.42), pigmentation (p = 0.002, φ = 0.60), erythema (p = 0.048, φ = 0.36), suppuration (p = 0.001, φ = 0.71), and granulation tissue (p = 0.032, φ = 0.30) compared with Group A, while no significant difference was observed in plate exposure (p = 0.25). EDX analysis revealed greater release of nickel, chromium, and iron in Group B, although binary distribution analysis of elements was not statistically significant (p = 0.157). These findings suggest that prolonged retention of stainless steel miniplates beyond one year increases tribocorrosion and metal ion release, correlating with higher complication rates. Early removal within 6-12 months, when clinically feasible, may help minimize corrosion-related risks and improve patient outcomes.