Objective To investigate the feasibility of using a new type carina type tracheal prosthesis made of complex material to replace trachea and carina defects. Methods According to biomechanics index, a new carina type tracheal prosthesis was designed and constituted with carbon fiber and silicon. 19 dogs were divided into two groups randomly: group A(n=11), the carina type tracheal prosthesis anastomosed directly to dog′s trachea and bronchus;group B(n=8), based on group A, meanwhile the diaphragm was incised and the pedicel caul was transplanted from abdominal cavity to thorax to enwrap the carina type tracheal prosthesis and anastomotic site. Results The average survival period post operation in group A and group B were (3.462?1.849)d and (6.475?1.062)d ,respectively. There was significant difference of the survival period between two groups(P

0.05).Conclusion The implanted radioactive 125I seeds can damage all kinds of tissues at different degrees,but this kind of damage is reversible,the dog may repair the damage through its own repair ability,its clinical application is safe.