Demineralized bone matrix (DBM) is often used to treat bone defects due to its osteoinductive and osteoconductive properties. The aim of this work is to evaluate the characteristics and evolution of the repair of experimental radial orthopaedic bone defects treated with DBM. DBM was prepared from rabbit bone obtained from cadavers, which were fragmented, defatted, demineralized and preserved in alcohol. Ten New Zealand rabbits were used. Critical size defects were created in one of the radiuses. The defects of 8 rabbits were filled with DBM while the other 2 rabbits did not receive any treatment. Each rabbit was radiologically followed at 15, 25, 40, 60 and 90 days. The untreated animals did not show presence of new bone in relation to the defect, whereas the DBM-treated defects were completely filled at day 90. The presence of new bone was evident from day 15 onward until the entire defect was repaired. The production of bone at each post operative period was statistically significant (P<0.0001) between the control examinations on days 15, 25 and 40, while at post operative days 60 and 90 there was no significant difference (P>0.05). The pattern of defects' repair started with presence of new bone at the extremes of defects and continued towards their centre.