Objective To evaluate the ability of inductive osteogenesis of allgraft demineralized bone containing basic fibroblast growth factor (bFGF/ALB) in repairing bone defect. Methods Thirty-two New Zealand white rabbits were randomly divided into four groups (groups A,B,C and D, n=8). A segmental bone defect of15 mm inlength was made on the bilateral radius respectively and the defects filled with ALB/bFGF in group A, with ALB in group B, with bFGF in group C and without any materials in group D serving as blank control. At 2, 4, 6 and 8 weeks after operation, all restored bones were evaluated by roentgenography, histological observation and Ca2+detection of osteotylus. Results The X-ray films showed that groups A and B had a little shadow of bone formation at 2 weeks, while groups C and D had transparent shadow; that group A had denser shadow and new bone formation at 4 weeks and 6 weeks, groups B and C had a little increase of shadow and group D had little shadow at fractured ends; and that group A had formation of bone bridge at 8 weeks, the new formed bone in fractured ends of group B closed with each other, the gap still existed in group C, and the defects filled with the soft tissue in group D. The Ca2+content of group A was higher than that of groups B, C and D at 4 weeks (Plt;0.05) and 8 weeks (Plt;0.01). The histological observaton showed that the degree of bone restoration of group A was superior to that of groups B, C and D. Conclusion bFGF/ALB is a good material to improve bone restoration.
Objective To study in vitro sustained release behaviour of the recombinant human bone morphogenetic protein 2(rhBMP-2) from the sample which porous calcium phosphate cement (PCPC) was combined with rhBMP-2, and to evaluate the effect of PCPC/rhBMP-2 composite on repairing bone defect in the animalstudy.Methods rhBMP-2 was absorbed into PCPC by vacuum-adsorption and freeze-dried at -40℃, the PCPC/rhBMP-2 enwrapped with chitosan as the experimental group, the pure PCPC/rhBMP-2 as the control group, then the sustained release ofrhBMP-2 from PCPC was determined in simulated body fluid (SBF) by UV-VIS spectrophotometer. At same time, the PCPC/rhBMP-2 composites with chitosan were implanted into the (4.2 mm×5.0 mm femora defects of rabbits, which were considered as the experimental group, whereas in the control group only PCPC was implanted. The effect of repairingbone defect was evaluated in the 4th and 8th week postoperatively by radiograph and histomorphology.Results The PCPC have a high absorption efficiency to rhBMP-2, and the release of rhBMP-2 was sustained release system. The release of rhBMP-2 from PCPC in the experimental group (99% after 350 hours) was slowerthan that in the control group (100% after 150 hours). In the experimental group, the radiological and histomorphological evaluations showed that theinterfaces between the materials and host bones became blurred both at 4th and 8th week. The implanted materials were partially absorbed, and the implanted areas exhibited the formation of new bone. In the control group, a little amount of new bones was observed. Conclusion The PCPC shows great clinical potential as a carrier for rhBMP-2. The PCPC/rhBMP-2 composite possesses much potentialities of osteoinductivity and the ability of repairing bone defect, so it can be used as a novel bone substitute clinically.
Objective To evaluate the effect of nano-hydroxyapatit e collagen (nHAC) bone and marrow mesenchymal stem cells (MSCs) on the treatment of rabbit osteonecrosis of the femoral head (ONFH) defect. Methods From June to October 2004, animal models of ONFH defect were established i n 45 New Zealand rabbits. They were divided into 3 groups randomly:In group A, as the control group, defect was not filled with any implants; In group B with nHAC; In group C with nHAC+MSC. Imaging and histological observation were made 4, 8, 12 weeks after operation. Results group C had a better o steogenesis ability than group B and group A. group B had a better osteogenesis ability than group A. Obvious new bones and osteogenesis were observed in group C 4 weeks after operation. The defect areas in group C were almost repaired 12 weeks after operation. Conclusion nHAC has a better effect of o steoconduction and it is a superior material for repairing bone defect of ONFH a nd of great value in treating ONFH when compounded with MSCs.
Objective To evaluate the clinical significance of submental island flap in repairing tongue defects.Methods Nine patients (6 men and 3 women)with tongue squamous cell carcinoma underwent subtotal or partial glossectomy, resection of mandible,radical neck dissection and immediate reconstruction of tongue defects with submental island flap. The age ranged from 48 years to 71 years, the lesion locations were right part of tongue (5 cases) and left part of tongue (4 cases). The defect sizes were 4.2 cm×3.2 cm to 5.5 cm×4.0 cm. The flap area rangedfrom 6.0 cm×3.0 cm to 7.0 cm×4.0 cm. The flap pedicle included submental artery in 8 cases and both submental artery and facial artery in 1 case. Results The submental island flap survived in 8 cases. Postoperative articulation and swallowing were investigated in all cases. The static shape of tongue after rec onstruction with submental island flap was acceptable. The dynamic speech, swallowing and food transport function were well preformed. No complication occurred.Three patients were given radiotherapy 3 weeks after operation. Conclusion It is simple and convenient to repair defects of tongue and oral floor with submental island flap.
Objective To investigate the clinical efficiency of thedistally based sural island flap and myofasciocutaneous flap in reconstruction of defect and osteomyelitic cavity of the ankle and foot. Methods From June 1997 to October 2004, 21 patients with soft tissue defects and osteomyelitis in the ankle and foot were treated with the distally based sural island flap and myofasciocutaneous flap. There were 20 males and 1 female aging from 6 to 78 years. The defect was caused by soft tissue defect trauma(18 cases) and electrical injury ( 3 cases). Among 21 patients, 17 were treated with island flaps, 4 by the myofasciocutaneous flap. The size of flaps ranged from 4 cm×5cm to 16 cm×22 cm. The donorsites were closed directly in 4 cases. Results The flaps completely survived in 21 cases and healing by first intention was achieved. After a follow-up of 36 months, no complication occurred. The color and texture of the flaps were good. The appearance and the function were satisfactory. Conclusion Distally basedsural flap is a reliable flap. This flap has rich blood supply without sacrifice of major arteries. Flap elevation is easy. It is very useful in repairing large soft tissue defects of the lower leg, the ankle and the foot, especially inrepairing deep soft tissue defects and osteomyelitic cavities .