To evaluate the effect of simulated intra-abdominal pressure on the delamination performance of biological mesh and the risk of hernia recurrence after implantation repair in Beagle dog full-layer abdominal wall muscle defect model.

Two commercially available biological meshes were selected as samples basement membrane/small intestinal submucosa (BM /SIS) composite mesh and small intestinal submucosa (SIS) mesh. To simulate the continuous force intra-abdominal environment of the biological mesh, the meshes were mechanically stretched for 20,000 cycles (stretching rate ±10% and ±20%) in a normal saline liquid environment, to study the effect of mechanical loading on the delamination performance. Four Beagle dogs were selected and the whole abdominal wall muscle was removed to construct the full-layer abdominal wall muscle defect model. Different biological meshes (BM/SIS, SIS) were used for repair. All the Beagle dogs were fed for 2 weeks after operation and then killed. The mesh and surrounding tissues were removed, and the delamination of mesh after implantation in animals and hernia recurrence were assessed.

After 20,000 cycles of mechanical stretching, the BM/SIS composite mesh did not show significant delamination and thickness change. Tissue repair after implantation in Beagle dogs with full-layer abdominal wall muscle defect had good repair effect, and no hernia recurrence was observed. The SIS mesh exhibited space increase and significant thickness change (P=0.007) under ±10% cycles of mechanical stretching, and significant and increasing thickness (P=0.001) under ±20% cycles of mechanical stretching. After 2 weeks of implantation, the SIS mesh was significantly delaminated and poorly integrated with the tissue.

The BM/SIS biological mesh has a stable interlayer structure, which is not easy to be delaminated. The strength of the BM/SIS mesh is stable, which can effectively prevent the risk of hernia recurrence caused by the delamination of the mesh.