THE PURPOSE OF THIS STUDY is to demonstrate the potential of using a barrier in the treatment of palato-gingival groove defects. The study group consisted of 10 patients. Prior to treatment, the palato-gingival groove on maxillary lateral incisors was measured with calibrated periodontal probe from the cemento-enamel junction (CEJ) to the free gingival margin (FGM) and from the FGM to the base of the pocket (BP). Probing depth (PD) was calculated and bleeding on probing indicated. Surgical procedures consisted of flap reflection, removal of granulation tissue, and scaling and root planing of the groove. An expanded polytetrafluoroethylene membrane was sutured over the palato-gingival groove. Six months postsurgery, all measurements were repeated. Statistical analysis compared results using means, standard deviations, and paired t tests. Results showed an improvement in clinical attachment gain, probing depth reduction, and decreased bleeding on probing. This study demonstrates the potential of guided tissue regeneration in the treatment of palato-gingival groove defects. A random blinded clinical trial is necessary, however, to fully assess the potential of this procedure in treatment of palato-gingival groove defects.