Abstract: Abstract: Objective: To evaluate the effects of the combination of OAM and GTR in the treatment of periodontal intrabonydefects. Methods: 46 patients(50 periodontal intrabonydefects)were randomized into two groups of treatment: group A- OAM /autologous bone /GTR (experimental group) and group B- autologous bone / GTR (control group) .The followings were recorded before the operation, 12 weeks and 24 weeks after the operation：periodontal probing depth (PPD)、clinical attachment loss(CAL)、 sulcus bleeding index(SBI) and alveolar bone height（AH）．The effects were analyzed statistically by SPSS12.0．Results: After the operation ,both of the indicators in the two groups were significantly improved than those on the baseline.PPD and CAL in group A were significantly lower than those in group B(P<0.05 at the 12th weeks ,P<0.01 at the 24th weeks)．No significant diference in SBI reduction was observed between group A and B (P>0.05)．CBCT showed that there was new bone formation in bone defect area in both groups, but AH in group A increased significantly compared with group B (P <0.05). Conclusions: The therapy of OAM / autologous bone / GTR is more effective than the autologous bone /GTR therapy in reducing PPD and CAL and alleviating periodontitis．It is concluded that OAM / autologous bone / GTR is the ideal way to treat periodontal intrabonydefects.