Objective  To explore the efficacy of a tissue engineering bone composed of biphasic ceramic biologic bone (BCBB)

bone morphogenetic protein (BMP)

basic fibroblast growth factor (bFGF) and mesenchymal stem cells (MSCs) in the repairing of necrotic areas of the femoral head.   Methods  The femoral head necrosis model of 64 femoral head in 32 rabbits was induced by microwave heating and then randomly divided into 4 groups

which were respectively implanted with nothing (group A)

with BCBB/BMP/bFGF (group B)

with BCBB/BMP/bFGF/MSCs (group C) and with cancellous bone autograft (group D). The specimens were harvested separately at the end of 2

4

8 and 12 weeks after operation. Four femoral heads were taken off at each interval in every group. A series of examinations were carried out including of gross anatomic observation

X-ray

histology

the calcium content and the ratio of calcium and phosphorus

and blood vessel immunohistochemical staining.    Results  (1) Gross anatomic observation: In group A

one femoral head collapsed at the end of 8 and 12 weeks respectively. In group B

granulation and fibrillar tissue began to proliferate actively by the end of 2 weeks. The boundary between the grafting substance and the post bone was unclear in group C and group D by the end of 12 weeks. (2) X-ray: At the 12th week

X-ray grade point indicated that group B

C

D was superior to group A (P0.05)

and among group B

C

and D

the difference was not significant (P0.05). (3) Histology: New bone area comparison by the end of 4

8 and 12 weeks showed Group C was superior to group B (P0.05)

and the difference between group C and D was not significant (P0.05). (4) Energy dispersion analysis X-ray (EDAX): The calcium content and the ratio of calcium and phosphorus in group B and group C was higher than that of group D at the 2nd

4th

and 8th weeks (P0.05). (5) At the 2nd

4th and 8th week

the area of new blood vessel in group B and  C was more than that of group A and D

and the difference was obvious (P0.05).   Conclusion  The tissue engineering bone (BCBB/BMP/bFGF/MSCs) is superior to BCBB/BMP/bFGF

and comparable to cancellous bone autograft in repairing rabbit femoral head necrosis.