Using a previously described experimental model for demonstration of osteoinduction biological activity of variably prepared fractions of demineralized bone matrix was studied. Sequential extraction of matrix using CaCl2, EDTA, LiCl and water results in an acceleration of the induction process and a reduction of immunological host reaction in the case of xenogenic implants. Application of chaotropic reagents such as guanidinium chloride and sodium thiocyanate has the consequency of lowering the inductive signal. From these results it is likely that noncollagenous constituents of bone matrix play a significant role in osteoinduction.