Experimental studies on an artificial trachea of collagen-coated poly(L-lactic acid) mesh or unwoven cloth combined with a periosteal graft.

Artificial tracheas were fabricated from poly(L-lactic acid) mesh or unwoven cloth coated with collagen in order to reconstruct the respiratory airway by self regeneration without retaining the prosthesis at the replacement site, thus preventing infection, air leakage, granulation tissue formation, and displacement of the prosthesis. Nine weeks after placing a periosteal autologous graft from the tibia around the cervical trachea of a rabbit, bone rings formed without infection. Two weeks after replacement of an 8 X 8 mm window-shaped section of the cervical trachea with autologous periosteum, the internal surface of the trachea was well epithelialized without local complications, but ossification was not seen. One week after cervical substitution with our 2 cm long artificial trachea combined with the periosteal graft, cartilage was produced around the mesh material but neither ossification nor epithelization was observed thereafter, probably due to local infection. On the other hand, cartilage, bone, and epithelium did not form around the unwoven cloth artificial trachea after the substitution, probably because of severe infection due to collapse of the tracheal lumen. However, the formation of bone rings around the trachea suggests preservation of the neotracheal lumen, which may have potential for the treatment of tracheomalacia and/or bronchomalacia.