The purpose of this study was to histologically evaluate the effectiveness of polylactide:polyglycolide 50:50 (DL-PLGA) as a barrier to prevent epithelial migration and to promote new connective tissue attachment. Mucoperiosteal flaps were performed on 17 human teeth. DL-PLGA membrane was placed over the roots and alveolar bone. DL-PLGA was not placed over control teeth. Ninety days following surgery, block sections were obtained and processed for histologic evaluation. All specimens revealed a mean length of epithelial attachment within physiologic limits and recession of the gingival margin. There was little or no reattachment of the connective tissue. It is concluded that this copolymer barrier did not prevent epithelial migration nor enhance connective tissue attachment to human roots with severe horizontal bone loss and active periodontal disease.