The aim of this study was to evaluate the repair of hard and soft tissue using Osteo Gen and comparing with flap curettage in periodontal defects. 36 periodontal intraosseous defects in sixteen patients involved moderate to advanced periodontitis were randomly selected and allocated to two groups: test (22) and control groups (14). Slow resorption, excellent tissue compatibility, no exfoliation and root resorption were considered during healing. The average of pocket depth in test and control groups was 3.16 and 2.73 mm, respectively. After 6 months, the average of bone repair was 2.18 mm (68.97%) and 0.46 mm (16.84%) in test and control groups. Bone apposition was obtained in test group (0.09 mm) (2.84%) while bone loss observed in control group (0.32 mm)(l 1.72%). Initial pocket depths in test and control groups were 7.68mm and 6.61mm. After six months, re-entry surgery was performed and the measurement of new attachment was 3.45 mm (61.19%) and 2.81 mm (51.28%). Recession of the gingival margin was 1.22 mm (15.80%) and 0,58 mm (8.77%) for test and control groups,respectively. By considering these findings, using of Osteo Gen can be recommended compare with flap curettage in periodontal intraosseous defects.