AbstractWe have previously demonstrated that primary rat osteoclasts behave differently when cultured on austenite and martensite Nitinol. In this study, we coated the two phases of Nitinol with plasma fibronectin and studied if this modifies the proliferation and cell cycle of MC3T3‐E1 osteoblasts. The influence of the crystalline structure of Nitinol on the remodeling and conformation of fibronectin was also studied. The results on austenite demonstrated that fibronectin was more strongly remodeled and the cells spread better compared with the martensite phase. Interestingly, the conformation of the protein showed no differences between austenite and martensite. In addition, fibronectin improved cell proliferation in both phases, but the effect of fibronectin coating was stronger on the austenite surface. In addition, in both Nitinol phases, the proportion of cells in the G1 phase was observed to grow in the presence of fibronectin. This could indicate cell differentiation on Nitinol. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009