The efficacy of periosteal cells compared to chondrocytes in the tissue engineered repair of bone defects.

We studied the efficacy of tissue generated from polymers seeded with periosteal cells and compared it to that of polymers seeded with chondrocytes, for its ability to repair surgically created cranial bone defects in rats. Large (approximately 40 mm2) bilateral defects were created in the parietal and temporal bones of 20 nude rats. One defect in each mouse was filled with synthetic biocompatible and biodegradable polymer templates seeded in vitro with either bovine periosteal cells (experimental group I) or chondrocytes (experimental group II). Contralateral defects were filled with either polymer not seeded with cells (control group I), or nothing at all (control group II). There was gross evidence of new bone formation repairing the defect in 7 of the 10 defects filled with polymers seeded with periosteal cells, while 8 of the 10 defects filled with polymers containing chondrocytes showed gross evidence of new cartilage formation covering the defect. Control defects showed no gross evidence of repair with either bone or cartilage.