Intra-bony defects remain a significant therapeutic problem in periodontal theraphy. Periodontal surgery with various bone grafts is being used. The aim of the study was clinical and radiographic evaluation of 6 months treatment efects following periodontal surgery with grafting procedures with Bio-Oss Spongiosa and Bio-Oss Collagen. The following clinical parameters were evaluated: probing pocket depth, clinical attachement level and gingival recession. Radiographic assessment included defect depth, width and radiographic Engelberger, Marthaler and Rateitschak index. Treatment was performed in 40 defects: 16 one-walled, 21 two-walled and 3 three-walled. Statistic analisis was carried out using t-tests. The follow-up examination performed 6 months following surgery found a statistic significant reduction of probing pocket depth and gain in clinical attachement level as well as reduction of radiographic defects depth and width and increase of radiographic Engelberger, Marthaler and Rateitschak index.