The pilot study deals with the clinical results of the regenerative therapeutical method in intraosseous periodontal defects done by surgical augmentation procedure using a material of a new generation prepared on the basis of a bioactive glass. A group of 10 individuals were treated properly for chronic periodontitis. Some of treated infraalveolar periodontal lesions, both periodontal pockets and interradicular defects, persisted or recurred in posterior teeth. In order to eliminate them they were indicated for advanced periodontal surgery or regenerative surgical therapy stimulating healing processes of supportive tissues, mostly alveolar bone around treated teeth. Relevant clinical parameters, i. e. values of the pocket depth, gingival recession, and loss of attachment were evaluated before and after the periodontal surgery and compared with each other. The therapy led to significant improvement of clinical parameters in terms of the reduction of pocket depth and loss of attachment values. and R. Slezák, V. Paulusová