Different implant surfaces modulate bone repair? Insights from histomorphometric and SEM/EDS analyses

Objective: Characterize the newly formed bone tissue adjacent to implant surfaces. Methods: The implants were previously analyzed by scanning electron microscopy (SEM) and energy dispersion X-ray spectroscopy (EDS) and installed in the right tibia of 75 rats divided into polished, machined, and treated groups. After euthanasia on 3, 7, 15, 21, and 40 postoperative days, histological analysis was performed to evaluate bone-implant contact. Results: At topographic analysis on the SEM, the polish group had the smoothest and regular surface and roughness surface in the treated group. On the EDS analysis, all groups had no contamination on the superficies and similar compouds (Titanium, Aluminum, and Vanadium). In terms of quality, the process of osseointegration was similar across all groups. However, a quantitative analysis showed that mature bone formed around the implant threads, even in areas near the bone marrow, with significant difference at seven days between the polished and treated groups. Conclusion: The peri-implant repair pattern was similar among all surface types in all other timelines, with cortical bone formation throughout the titanium surface of the three implant groups. The acid-etched surface treatment group showed faster bone differentiation.