This study evaluated the use of a bioresorbable membrane (Guidor USA) for treatment of periodontal angular bone defects in eight periodontitis patients. Presurgical measurements consisted of probing depth, clinical attachment levels, and digital radiographic imaging evaluation. Full-thickness buccal and lingual flaps were elevated allowing for soft tissue debridement, scaling, and root planing. Bioresorbable membranes were placed in at least one of the periodontal defects, and controls were left without barrier placement. Clinical and radiographic results 6 months after the surgical procedure showed clinical and radiographic improvement for control and test lesions. However, sites treated with bioresorbable membranes presented a significant gain in clinical attachment and bone mass when compared to sites that had received flap surgery alone.