Effect of a hierarchical hybrid micro/nanorough strontium-loaded surface on osseointegration in osteoporosis

This study compared the effect of a hierarchical hybrid micro/nanorough titanium strontium-loaded (MNT-Sr) surface on osseointegration under osteoporotic conditions to those of implants with a smooth titanium surface (ST), microrough titanium surface (MT) etched with hydrofluoric acid (HF), and an NT-Sr surface obtained by magnetron sputtering. The MNT-Sr surface released Sr at a low rate over a long period. In vitro experiments showed that although the MT was the superior surface in terms of promoting bone marrow stromal cells (BMSCs) adhesion and proliferation, the MNT-Sr surface had better biocompatibility for BMSCs differentiation and induced more intercellular junctions than the other surfaces. After 12 weeks of implantation into the distal femurs of ovariectomized rats, MNT-Sr had the highest osseointegration, followed by MT, NT-Sr, and ST surfaces. These results suggest that MNT-Sr combines the advantages of hierarchical micro/nanotopography and Sr to enhance osseointegration in osteoporosis.