A mucogingival grafting procedure has been developed to cover denuded root surfaces. The subepithelial connective tissue graft is composed of a free connective tissue graft and an overlying pedicle graft. The source of connective tissue graft were trap door approach and thining of a full thickness palatal flap. The purpose of this study was compare a two different connective tissue obtaining method. In this study, where palatal pocket was present, pocket elimination was performed, and the tissue normally discarded after thinning of the palatal flap was used as a grafting material. The results were as follows : 1. The mean difference between trap door approach and thinning procedure for root coverage were $2.1{pm}O.lmm$, $2.2{pm}O.2mm$. 2. The mean difference between trap door approach and thinning procedure for pocket depth change were $O.2{pm}O.lmm$, $O.2{pm}O.2mm$. 3. The mean difference between trap door approach and thinning procedure for attachment gain were $2.1{pm}O.2mm$, $2.4{pm}O.2mm$. 4. The esthetics in recipient site, both color match and tissue contour, were acceptable to the patient in all cases. 5. Therefore, thinning procedure were similar to trap door approach in root coverage effect.