Titanium implants with modified surfaces: Meta-analysis of in vivo osteointegration

• Various titanium specimens were studied in vivo on osteointegration vs their properties.
• Non-porous implants had a better performance when coated with bioactive glass.
• Porous implants have shown the best results for hydrothermally treated specimens.
• Good correlation was found with the previous in vitro tests.
• New analysis of the in vivo data has shown benefits to assess biomaterials performance.

Titanium-based implants are widely used in modern clinical practice, but their “optimal” properties in terms of porosity and topology, roughness and hydrophilic parameters are being a subject of intensive discussions. Recent in vitro results have shown a possibility to optimize the surface of an implant with maximal repelling of bacteria (Staphylococcus aureus, Staphylococcus epidermidis) and improvement in human osteogenic and endothelial cell adhesion, proliferation and differentiation. In this work, these different grades titanium implants were tested in vivo using the same analytical methodology. In addition to material parameters, key histomorphometrical parameters such a regeneration area, bone adaptation area and bone-to-implant contact were determined after 2 and 4 weeks of implantation in rabbit animal model. Porous implants have more clear differences than non-porous ones, with the best optimum values obtained on hydrothermally treated electrophoretically deposited titanium. These in vivo data correlate well with the optimal prediction made by in vitro tests.