The Experimental Study Of Silk Mesh In The Repair Of Ventral Hernia In Rats

[Background and Purpose]Although Ventral hernia accounts for only about 15%of all external abdominal hernias,the condition and treatment are more difficult and complicated.Currently,hernia mesh repair is the first choice in clinical practice.Currently,there is no material mesh that can meet the needs of all patients.Silk has better biocompatibility and biomechanical properties.Silk protein-derived biomaterials have become a new material in tissue engineering and regenerative medicine.We tried to explore the feasibility of silk protein mesh in abdominal wall herniorrhaphy by means of animal experiment,so as to further apply it in clinical practice.[Methods]The model of abdominal hernia defect was made in SD rats by operation.Group A(intraperitoneal adhesion group):after laparotomy,meshs of different materials were used on both sides of the abdominal cavity for repair.Group B(model of small abdominal wall defect):a full-thickness abdominal wall defect was made on the left and right of the abdominal muscle layer,and the defect was covered with meshs of different materials.Group C(giant abdominal wall defect):a full-thickness giant defect was made in the middle of the abdominal wall and covered with meshs of different materials.Polyester mesh and composite mesh,which are commonly used in clinical practice,were set as the control group and silk mesh as the experimental group.The general postoperative conditions of each group were observed and statistically analyzed.Rats were sacrificed and the adhesion and shrinkage of mesh in abdominal cavity were compared.The histopathological changes of different mesh were compared by paraffin section staining.Statistical analysis of the above variables,from many aspects of silk mesh has clinical application prospects.[Result](1)There was no significant difference in adhesion score between the abdominal cavity and the lateral abdominal muscle mesh.(2)the adhesion of silk mesh in the abdominal cavity was significantly lighter than that of polyester mesh(P<0.001),with no significant difference from that of composite mesh(P=0.88).(3)the contraction rate of polyester mesh in the abdominal cavity was higher than that of the lateral abdominal muscle(P<0.001),while that of silk mesh and composite mesh was on the contrary(P<0.001).(4)the shrinkage rate of silk mesh was lower than that of polyester mesh(P<0.001),but higher than that of composite mesh(P<0.05).(5)the inflammatory response of silk mesh was similar to that of composite mesh(P=0.71)and significantly lower than that of polyester mesh(P<0.001).(6)fiber proliferation of silk mesh was similar to that of polyester mesh(P=0.26)and significantly higher than that of composite mesh(P<0.001).(7)there was no significant difference in angiogenesis between the three kinds of mesh(P>0.05).(8)Due to the rapid degradation,there is still insufficient tension resistance in the silk mesh,which may lead to the recurrence of abdominal hernia.[Conclusion]Silk mesh can be used as hernia repair material and directly placed in the abdominal cavity for repair due to slight adhesion,low shrinkage,mild inflammatory reaction and strong fibrous hyperplasia in the abdominal cavity.However,the mesh degradation rate is relatively fast,which may lead to hernia recurrence.Therefore,the production process needs to be further improved.