The recent trend of research and development on guided tissue regeneration focuses on the biodegradable membranes, which eliminate the need for subsequent surgical removal. They have demonstrated significant and equivalent clinical improvements to the ePTFE membranes. This study evaluate guided tissue regeneration wound healing in surgically induced intrabony periodontal defects following surgical treatment with a synthetic biodegradable membranes, made from a copolymer of glycolide and lactide, in 8 beagle dogs. After full thickeness flap reflection, exposed buccal bone of maxillary and mandibular canine and premolar was removed surgically mesiodistally and occlusoapically at $6mm{ imes}6mm$ in size for preparation of periodontal defects. In experimental sites a customized barrier was formed and fitted to cover the defect. Flap was replaced slightly coronal to CEJ and sutured. Plaque control program was initiated and maintained until completion of the study. In 4, 8, 16 and 24 weeks after surgery, the animals were sacrificed and then undecalcified specimens were prepared for histologic evaluation. Histologic examination indicated significant periodontal regeneration characterized by new connective tissue attachment, cementum formation and bone formation. These membranes showed good biocompatibility throughout experiodontal period. The barriers had been completely resorbed with no apparent adverse effect on periodontal wound healing at 24 weeks. These results implicated that present synthetic biodegradable membrane facilitated guided tissue regeneration in periodontal defect.