Recently, it was reported that enamel matrix derivative may be beneficial in periodontal regeneration procedures in expectation of promoting new bone and cementum formation. The aim of present study was to evaluate the effect of enamel matrix derivative($Emdogain^?$)and Caso4 sulfate paste in 1-wall intrabony defects in beagle dogs. Surgically created 1-wall intrabony defects were randomly assigned to receive root debridement alone or $Emdogain^{(R)}$ or $Emdogain^{(R)}$ and Caso4. Clinical defect size was 4 X 4mm. The control group was treated with root debridement alone,and Experimental group I was treated with enamel matrix derivative application, and Experimental group II was treated with enamel matrix derivative and Caso4 sulfate paste application,. The healing processes were histologically and histometrically observed after 8 weeks and the results were as follows: 1. The length of junctional epithelium was $0.41{pm}0.01mm$ in the control group, $0.42{pm}0.08mm$in the experimental group I and $0.50{pm}0.13mm$in the experimental group II. 2. The connective tissue adhesion was $0.28{pm}0.02mm$ in the control group, $0.13{pm}0.08mm$ in the experimental group I and $0.19{pm}0.02mm$ in the experimental group II. 3. The new cementum formation was $3.80{pm}0.06mm$ in the control group, $4.12{pm}0.43mm$ in the experimental group I and $4.34{pm}0.71mm$ in the experimental group II. 4. The new bone formation was $1.43{pm}0.03mm$ in the control group, $1.53{pm}0.47mm$ in the experimental group I and $2.25{pm}1.35mm$ in the experimental group II. Although there was limitation to present study, the use of enamel matrix derivative in the treatment of periodontal 1-wall intrabony defect enhanced new cementum and bone formation. Caso4 sulfate paste will be the candidate for carriers to deliver enamel matrix derivative, and so enhance the regenerative potency of enamel matrix derivative.