The invention describes for first time the activity of poloxamines as inducers in the differentiation of mesenchymal or progenitor cells. In particular, the invention demonstrates that poloxamines have an osteogenic ability. The invention relates to the use of one or more poloxamines or a pharmaceutical composition comprising same for the preparation of a drug for treting patients with bone defects in general. The invention also relates to a method for inducing the differentiation of mesenchymal or progenitor cells into osteoblasts by bringing said cells into contact with a sterilised aqueous dispersión or solution of one or more poloxamines.