Relevance. Reconstructive periodontal surgery is one of the most effective methods of restoring tooth-supporting apparatus damaged by microbial inflammation and destruction. For this purpose, they use non-resorbable and resorbable biomaterials, which act as a temporary barrier between the tissues with different mitotic potential during early healing. Since the properties of barrier membranes determine the degree of invasiveness and postoperative morbidity, and, finally, the success of the surgery, it is relevant to study the outcomes of periodontal reconstruction with one of the modern collagen membranes cross-linked by ribose.Purpose. To comparatively assess the outcomes of periodontal reconstructions with a resorbable and non-resorbable barrier material.Material and methods. The study is a prospective randomized blind controlled clinical trial. The study included 37 patients (14 men, 23 women) aged 45-65 years, who, after the initial therapy, underwent 62 guided tissue regenerations using e-PTFE and resorbable collagen membrane cross-linked by ribose. The study compared the clinical and radiographic results before and 18 months after the surgery. We evaluated the probing depth (periodontal pocket), gingival recession level, loss of clinical attachment level, width and height of periodontal infrabony defects, gain in clinical attachment level. The material was statistically processed using StatSoft STATISTICA 10.0.1011 for Windows. The statistical unit is a periodontal defect.Results. In the postoperative period, the main (31%) and control (42%) groups exhibited the areas of membrane exposure; 16 periodontal defects, only in the control group, demonstrated the extensive membrane exposure, of which 11 membranes were prematurely removed due to infection of the reconstruction site. In the main group, fibrin allowed exposed area healing in the usual time without medical assistance. After 18 months, the gain in the clinical attachment level was 3.5 mm in the main group versus 2.8 mm in the control group (at p=0.03) with a significant decrease in the probing depth compared to that before treatment; the level of recession also changed positively, although not significantly. The type of periodontal defect (the parameter is higher in three-wall and two-wall defects) appeared to remarkably influence the gain in clinical attachment level.Conclusion. The study evidenced that the resorbable cross-linked collagen membrane demonstrated clinically acceptable outcome of the damaged periodontium reconstruction due to, first of all, increased predictability of the course of the early postoperative period, a significant reduction in morbidity and invasiveness of intervention.