Porous Ti6Al4V with controlled oxidation toward improved osseointegration of dental implant.

Background: Titanium (Ti) implants are known to be bioinert, stress shielding, and poor osseointegration, due to modulus discrepancy with native bone. This research aims to design a porous Ti6Al4V implant with controllable oxidation to mimic the natural bone properties for better osseointegration. Materials and Methods: Porous Ti6Al4V foams were manufactured by coagulant-assisted metal foaming with egg white protein and citric acid as stabilizing matrix. The detailed characterization was conducted using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, nanoindentation, and microcomputed tomography (micro-CT) to characterize microstructural, porosity, and mechanical properties. MTT assay and dual staining were used to study in vitro cytocompatibility using the human amniotic mesenchymal stem cells. In vivo biocompatibility and bone regeneration were evaluated through the rabbit femoral defect model at 4 and 12 weeks, using histology and micro-CT for bone ingrowth quantification. Results: The fabricated porous Ti6Al4V implants had 71%-75% porosity, facilitating nutrient transport and cellular ingrowth. Compressive modulus (284 MPa), measured via mechanical testing, was comparable to that of trabecular bone. In vitro studies demonstrated good cell viability and proliferation. In vivo, robust new bone formation was observed (~52% increase in bone volume), with over 90% tissue integration compared to control. Conclusions: Controlled oxidation of porous Ti6Al4V foam could provide a potential way to overcome the current limitations of dental implants. The improved biomechanical compatibility and osseointegration support its potential for clinical application in implantology.