Bone Compatibility of Experimental Ti–Ag and Ti–Cu Alloy Dental Implants in a Beagle Dog Model

Titanium–silver (Ti–Ag) and titanium–copper (Ti–Cu) alloys have been developed to improve the mechanical properties and machinability of titanium (Ti) for dental applications while maintaining corrosion resistance comparable to that of pure Ti. Herein, cylindrical dental implants composed of experimental Ti–20Ag, Ti–30Ag, Ti–5Cu, and Ti–10Cu (mass%) alloys were fabricated and implanted into the jawbones of beagle dogs to evaluate bone compatibility. Pure Ti and Ti–6Al–4V alloy implants were used as controls. Because the implant surfaces were mechanically polished, the experimental alloys, which exhibited higher hardness than Ti, showed lower surface roughness than Ti. Radiographic observations revealed no remarkable bone resorption around any implants during the experimental period. Histological evaluation demonstrated new bone formation and partial bone contact around implants at 1 and 3 months post-implantation. Although the bone–implant contact ratio was relatively low owing to the cylindrical implant design and limited initial stability, no significant differences were observed between the experimental alloys and Ti. These results indicate that Ti–Ag and Ti–Cu alloys improve mechanical properties while maintaining bone compatibility comparable to that of Ti, suggesting their potential as candidate materials for dental implant applications, particularly for narrow dental implants.