Usefulness of polyglycolic acid-polypropylene composite scaffolds for three-dimensional cartilage regeneration in a large-animal autograft model.

Approaches to auricular reconstruction have shown improved outcome when a basic fibroblast growth factor (bFGF) slow-release system and fibrin spraying are combined with biodegradable polymers. More complex, three-dimensional structures, such as those that replicate the human auricle, are often lost because of biodegradation of the synthetic scaffold. To improve the mechanical strength of regenerated cartilage, the authors grafted canine autologous chondrocytes after seeding onto scaffolds made of a complex of polyglycolic acid and polypropylene, incorporating a slow-release bFGF system with a fibrin spray coating. Five weeks after grafting, thicker cartilage with increased bending stress was obtained with the slow-release bFGF. In a three-polyglycolic acid-layer construct sandwiched around polypropylene, simulating a three-dimensional auricular structure, greater cartilage regeneration and angiogenesis were found around the implant. Sox5-positive cells were identified, indicative of maturation of neocartilage with chondroblast proliferation. These results support the usefulness of combining absorbable and nonabsorbable materials (polyglycolic acid and polypropylene) in composite scaffolds for autologous cartilage regeneration in a large-animal autograft model.