Dimensional Stability of Polymer and Titanium Implant Scan Bodies After Repeated Steam Sterilization: A High-Resolution 3D Metrological In Vitro Study

The increasing adoption of digital workflows in implant dentistry relies heavily on the accuracy of implant scan bodies (ISBs), which may be affected by repeated sterilization. This in vitro study evaluated the effect of 50 steam sterilization cycles on the dimensional stability of polymer and titanium ISBs. A total of 100 test specimens (n = 50 per material) were scanned before (T0) and after sterilization (T50) using a high-resolution intraoral scanner, generating 900 STL datasets for metrological analysis. Surface deviation, linear displacement, and angular deviation were assessed using validated industrial and dental software, with statistical evaluation performed through paired tests and linear mixed-effects models. Both materials exhibited statistically significant dimensional changes after sterilization (p < 0.001). Titanium scan bodies demonstrated greater linear deformation (69.76 μm) compared to polymer ones (49.50 μm), while maintaining superior angular stability (0.21° vs. −1.69° mean angular change in the polymer group). A significant interaction between material type and sterilization was observed. Despite high baseline precision, repeated autoclaving induced clinically relevant deviations in both materials. These findings indicate that cumulative sterilization cycles adversely affect ISB accuracy and highlight the importance of adhering to manufacturer recommendations to ensure optimal prosthetic outcomes.