Objective: The aim of this study is to evaluate the histological and clinical outcomes of intrabony defects treatment using regenerative periodontal therapy with enamel matrix proteins (Emdogain, EMD). Material And Method:Ten patients with chronic periodontitis were included in this randomized, controlled clinical study. Two groups received conservative periodontal therapy. In the test group, different teeth received regenerative treatment with EMD. In the control group only conservative periodontal therapy was performed. The following parameters were recorded at baseline and after 8 months: pocket probing depth (PD) and histological examinations. Results:Both groups showed a significant reduction of PD. The teeth treated with EMD showed a significant attachment gain. Within the test group, the radiographic examination of the teeth treated with EMD showed no significant change, whereas the teeth in the control group showed significant bone reduction. Conclusion:Treatment of intrabony defects with EMD may lead to substantially higher gains in clinical attachment and defect filling. The use of EMD in dental practice can prevent further bone loss.