The most commonly used barrier membrane material in guided tissue regeneration is absorbable collagen membrane. Although the collagen membrane has a good barrier effect, it lacks the growth factors needed for periodontal tissue regeneration, which affects the effect of collagen membrane on periodontal tissue regeneration. Extracellular Matrix Scaffold of Small Intestinal Submucosa (SIS) Membrane is a novel absorbable membrane that retains the extracellular matrix structure and is conducive to vascular ingrowth and tissue repair. The in vitro study showed that SIS membrane had excellent biocompatibility and certain antibacterial effect. Preclinical study also showed that SIS membrane significantly promoted the differentiation of bone marrow mesenchymal stem cells into osteoblasts, and promoted bone regeneration more effectively than collagen mechanism materials. SIS membrane can be used in soft tissue wound repair, guided bone regeneration, site preservation and other surgeries, and has achieved good therapeutic effects. However, whether the application of SIS membrane can achieve good therapeutic effect on periodontal guide tissue regeneration is still unclear. Therefore, in this study, the effects of guide tissue regeneration with collagen membrane and SIS membrane were compared through a randomized controlled clinical study.

Inclusion Criteria:

• periodontitis patients with stage III to IV, grade C had one or more intrabony defects with a depth of ≥3 mm; PD≥5mm after initial periodontal therapy.

Exclusion Criteria:

• smokers, pregnant female, other systematic disease