Bone marrow stromal cells response to nanorough titanium surfaces

Objectives: The aim of this study was to evaluate the effect of nanorough titanium implant surfaces on the response of human bone marrow stromal cells (BMSCs) in terms of adhesion, proliferation and osteogenic differentiation. Methods: 10x10 mm machined (M) and nano-roughened (Nano) titanium samples (P.H.I. s.r.l., San Vittore Olona, Milano, Italy) were examined by scanning electron microscopy (SEM). Primary cultures of BMSCs, obtained from bone marrow samples of healthy donors, were seeded on the titanium samples and cell morphology, adhesion and proliferation were evaluated. Furthermore, the osteogenic differentiation, in terms of alkaline phosphatase activity, osteocalcin synthesis and extracellular mineralization, was also analysed. Results: M samples appeared grooved, whereas Nano surfaces showed a peculiar nanoscaled topography at the SEM analysis. Cells appeared intimately spread on both surface types. 6-h cell adhesion was enhanced by Nano surfaces (p<0.05) with respect to machined ones, whereas the 7-d proliferation remained unmodified. Osteogenic parameters were increased (p<0.05 at least) by Nano samples compared to control machined ones. Conclusions: Nano-roughening treatment seems to enhance the adhesion of BMSCs onto titanium implant surfaces as well as their differentiation toward the osteoblastic phenotype. Further studies are needed to investigate the possible in vivo and clinical implications of such encouraging preliminary results.