Objective To investigate the effect of repairing bone defect with tissue engineered bone seeded with the autologous red bone marrow (ARBM) and wrapped by the pedicled fascial flap and provide experimental foundation for cl inicalappl ication. Methods Thirty-two New Zealand white rabbits (male and/or female) aged 4-5 months old and weighing2.0-2.5 kg were used to make the experimental model of bilateral 2 cm defect of the long bone and the periosteum in the radius. The tissue engineered bone was prepared by seeding the ARBM obtained from the rabbits on the osteoinductive absorbing material containing BMP. The left side of the experimental model underwent the implantation of autologous tissue engineered bone serving as the control group (group A). While the right side was designed as the experimental group (group B), one 5 cm × 3 cm fascial flap pedicled on the nameless blood vessel along with its capillary network adjacent to the bone defect was prepared using microsurgical technology, and the autologous tissue engineered bone wrapped by the fascial flap was used to fill the bone defect. At 4, 8, 12, and 16 weeks after operation, X-ray exam, absorbance (A) value test, gross morphology and histology observation, morphology quantitative analysis of bone in the reparative area, vascular image analysis on the boundary area were conducted. Results X-ray films, gross morphology observation, and histology observation: group B was superior to group A in terms of the growth of blood vessel into the implant, the quantity and the speed of the bone trabecula and the cartilage tissue formation, the development of mature bone structure, the remolding of shaft structure, the reopen of marrow cavity, and the absorbance and degradation of the implant. A value: there was significant difference between two groups 8, 12, and 16 weeks after operation (P lt; 0.05), and there were significant differences among those three time points in groups A and B (P lt; 0.05). For the ratio of neonatal trabecula area to the total reparative area, there were significant differences between two groups 4, 8, 12, and 16 weeks after operation (P lt; 0.05), and there were significant differences among those four time points in group B (P lt; 0.05).For the vascular regenerative area in per unit area of the junctional zone, group B was superior to group A 4, 8, 12, and 16 weeks after operation (P lt; 0.05). Conclusion Tissue engineered bone, seeded with the ARBM and wrapped by the pedicled fascial flap, has a sound reparative effect on bone defect due to its dual role of constructing vascularization and inducing membrane guided tissue regeneration.
Objective To study the vascularization of the compositeof bone morphogenetic protein 2 (BMP-2) gene transfected marrow mesenchymal stem cells (MSCs) and biodegradable scaffolds in repairing bone defect. Methods Adenovirus vector carrying BMP-2 (Ad-BMP-2) gene transfected MSCs and gene modified tissue engineered bone was constructed. The 1.5 cm radial defect models were made on 60 rabbits, which were evenly divided into 4 groups randomly(n=15, 30 sides). Different materials were used in 4 groups: Ad-BMP-2 transfected MSCs plus PLA/PCL (group A), AdLacz transfected MSCs plus PLA/PCL (group B), MSCs plus PLA/PCL (group C) and only PLA/PCL scaffolds (group D). The X-ray, capillary vessel ink infusion, histology, TEM, VEGF expression and microvacular density counting(MVD) were made 4, 8, and 12 weeks after operation. Results In group A after 4 weeks, foliated formed bones image was observed in the transplanted bones, new vessels grew into the bones, the pores of scaffolds were filled with cartilage callus, osteoblasts with active function grew around the microvessels, and VEGF expression and the number of microvessels were significantly superior to those of other groups, showing statistically significant difference (Plt;0.01); after 8 weeks, increasingly more new bones grew in the transplanted bones, microvessels distended and connected with each other, cartilage callus changed into trabecular bones; after 12 weeks, lamellar bone became successive, marrow cavity recanalized, microvessels showed orderly longitudinal arrangement. In groups B and C, the capability of bone formation was weak, the regeneration of blood vessels was slow, after 12 weeks, defects were mostly repaired, microvessels grew among the new trabecular bones. In group D, few new vessels were observed at each time, after 12 weeks, broken ends became hardened, the defectedarea was filled with fibrous tissue. Conclusion BMP-2 gene therapy, by -upregulating VEGF expression, indirectly induces vascularization ofgrafts,promotes the living of seed cells, and thus accelerates new bone formation.
Icariin（ICA） is one of the main active ingredients in the Berberidaceae family Epimedium. It makes a variety of biological activities, such as promoting bone formation, antibacterial and anti-inflammatory, and regulating immunity. Periodontitis is a chronic inflammatory disease that is present in the soft and hard tissues of the periodontium. The ultimate goals of its treatment are the reconstruction of periodontal tissues and bone defect repairing. At present, conventional treatment of periodontitis fails to achieve the ideal periodontal tissue regeneration. In recent years, the rapid development of tissue engineering technology has brought new ideas for the treatment of periodontal disease and bone defect repairing. Because of its anti-inflammatory and osteogenic effects, ICA has great potential for the treatments of periodontitis and bone defect repairing. This paper summarizes the effect and the molecular mechanism of ICA in the treatment of periodontitis and bone defect repairing, and discusses its application prospect as a drug for periodontal adjuvant therapy. This paper aims to provide a theoretical basis for the research and application of ICA in periodontitis treatment and bone defect repairing.
OBJECTIVE: To study the reparative and reconstructive methods for the large bone defect due to the excision of bone tumor. METHODS: According to the size and shape of the bone defect, we selected the proper bone and joint or manipulated bone segment of the profound hypothermia freezing allograft and gave locked intramedullary nails or steel plate and screws for stable internal fixation. RESULTS: In the 22 cases, 20 survived without tumor and 2 died. One patient treated with the allograft of semi-knee joint was found rejection. Then the wound did not heal. After the skin flap grafting was performed, the wound still did not heal, so the patient accepted amputation(4.5%). In the other 21 cases, the X-ray and 99mTc SPECT showed some callus or concentration of nuclein which implied bone union. According to Markin bone graft criterion, the excellent rate of function recovery was 81.8%. CONCLUSION: Allografting of bone and joint is a good and workable method in repairing and reconstructing the bone defect due to the excision of bone tumor. It should be further studied and be applied.
OBJECTIVE: To investigate the availability of bone defect repair by degradable porous polycaprolactam (PCL) as the carrier of bone morphogenetic protein (BMP). METHODS: Three different kinds of bone substitutes, including decalcified bone matrix, PCL-BMP compounds and simple PCL, were implanted into the radial bone defects in 36 rabbits, and in the other 12 rabbits the bone defects were left untreated as control. X-ray examination, X-ray morphometry, histological and electron microscopic observation were performed at different time after operation. RESULTS: The quantity of new bone formation in PCL-BMP group was prior to that in simple PCL group. The pattern and speed of bone defect repair in PCL-BMP group were similar to those in decalcified bone matrix. Electron microscopic observation showed that the PCL-BMP group degraded faster than simple PCL group, which was more suitable for bone repair. CONCLUSION: PCL is a good carrier of BMP with potential for clinical use.
The treatmen t of the bone defect of the distal part of the radiu s included repair of the bone defect and resto rat ion of the funct ion of the w rist jo in t. Since 1979, th ree operat ive methods w ere u sed to t reat 13 cases, and they w ere graf t ing of the vascu larized f ibu la by anastom rsis f ibu lar vessels, graf t ing of upper part of f ibu lar w ith lateral inferio rgen icu lar artery and graf t ing vascu larized scapu la f lap. Follow up had been carried ou t from1 to 10 years. The resu lt w as sat isfacto ry. The discu ssion included the repair of the defect of the m iddle o r distal part of the radiu s, the operat ive methods, main at ten t ion s and indications. It was considered that it shou ld be based on the length of bone defect wh ile the operative method was considered.
Objective To investigate the curative effects of homograft of the mesenchymal stem cells(MSCs) compbined with the medical collagen membrane of the guided tissue regeneration(MCMG) on the full thickness defects of the articular cartilage. Methods MSCs derived from New Zealand rabbits aged 3-4 months weighing 2.1-3.4 kg were cultured in vitro with a density of 5.5×108/ml and seeded onto MCMG. The MSC/MCMG complex was cultured for 48 h and transplanted into the fullthickness defects on the inboardcondyle and trochlea. Twenty-seven healthy New Zealand rabbits were randomly divided into 3 groups of 9rabbits in each. The cartilage defects in the inboard condyle and trochlea werefilled with the auto bone marrow MSCs and MCMG complex (MSCs/ MCMG) in Group A (Management A), with only MCMG in Group B (Management B)and with nothing in Group C (Management C). Three rabbits were killed at 4, 8 and 12 weeks after operation in each group, and the reparative tissue samples evaluated grossly,histologically and immunohistochemically were graded according tothe gross and histological scale. Results Four weeks after transplantation, the cartilage and subchondralbone were regenerated in Group A;for 12 weeks, the regenerated cartilage gradually thicked; 12 week after transplantation, the defect was repaired and the structures of the carticular surface and subchondral bone was in integrity.The defects in Group A were repaired by the hylinelike tissue and the defects in Groups B and C were repaired by the fibrous tissues. Glycosaminoglycan and type Ⅱcollagen in Groups A,B and C were reduced gradually.The statistical analysis on the gross at 12 weeks and the histologicalgradings at 4 weeks,8 weeks and 12 weeks showed that the inboardcondylar repairhad no significant difference compared with the rochlearepair(Pgt;0.05).Management A was significantly better than Managements B and C (Plt;0.05), and Management B was better than Management C(Plt;0.05). Conclusion Transplantation of the MSCs combined with MCMG on the full thickness defects of the articular cartilage is a promising approach to the the treatment of cartilage defects. MCMG can satisfy the demands of the scaffold for the tissue-engineered cartilage.
【Abstract】 Objective To investigate the effectiveness of the medical calcium sulfate—OsteoSet bone graft substitute in the treatment of defect after excision of jaw cyst. Methods Between December 2009 and May 2010, 15 cases of jaw cystic lesion were treated，including 9 males and 6 females with an average age of 36.6 years (range, 15-75 years). Orthopantomography (OPT) method was used to measure the cyst size before operation, and the size ranged from 1.5 cm × 1.5 cm to 8.0 cm × 3.0 cm. The range of bone defect was from 1.5 cm × 1.5 cm × 1.5 cm to 8.0 cm × 3.0 cm × 3.0 cm after cyst excision intraoperatively. The patients underwent cyst curettage and OsteoSet bone graft substitutes implantation (2-15 mL). Radiological method was used to evaluate the repair effect of OsteoSet pellets. Results The pathology biopsy was periapical cyst in 7 cases, odontogenic keratocyst in 5 cases, and dentigerous cyst in 3 cases. Fifteen patients were followed up 6-12 months. Thirteen patients achieved wound healing by first intention; 2 cases had longer drainage time (5 and 7 days, respectively), the incision healed after the pressure bandage. Swelling occurred in 1 case after 1 month with no symptom of infection. No postoperative infection and rejection was found. The X-ray examination showed that the materials filled the bone defect well after 1 day of operation. OsteoSet bone graft substitutes were absorbed by one-half after 1 month of operation and totally after 3 months by OPT. The low density area was smaller in the original cysts cavity, and high density in the cysts increased significantly with fuzzy boundaries of cysts. At 6 months after operation， there was no obvious difference in image density between the original cavity and normal bone, and the capsule cavity boundary disappeared, and defect area was full of new bone. Conclusion The medical calcium sulfate—OsteoSet bone graft substitute is an ideal filling material for bone defect.
OBJECTIVE: To evaluate clinical outcome of bone or osteoarticular allografts. METHODS: From September 1991 to November 1997, large bone or osteoarticular defects secondary to bone tumors resection in 36 patients and severe trauma in 2 patients were repaired by deep frozen or lyophilized allogeneic osteoarticular or diaphysis graft. RESULTS: No obvious immune rejection to the grafts was observed in most of the patients in early stage after operation. The patients were followed up from 1 year and five months to 7 years and five months with an average of 4.2 years. Limb function was satisfactory in 74.19% of the 31 survival patients with large osteoarticular or diaphysis allografts. CONCLUSION: Cryopreserved or lyophilized allogeneic osteoarticular grafts with decreased antigenicity and good biocompatibility are suitable materials for repairing large bone or osteoarticular defects.
Objective To investigate the ability of the biodegradable polycaprolactone (PCL) material to repair bone defect and to evaluate the feasibility ofusing the PCL as the scaffold in tissue engineering bone. Methods The bone defect models of 4.5 mm×12 mm were made in the bilateral femoral condyle of 65 NewZealand white rabbits. The PCL cylinder was implanted into the right side of defect(experimental group, n=60), the high dense crystality hydroxyapatite was implanted into the left side of defect (control group, n=60), and the incision was sutured without any implants (blank group, n=5). The samples were harvested and observed by examinations of gross, X-ray, bone density,99mTc-MDP bone scanning, γ-display ratio and scanning electron microscope (SEM) after 3, 6, 9 and 12 months of operation. The results were compared between the experimental group and control group. Results At 3, 6, 9 and 12 months after operation, the gross and X-ray examinations indicated that the bone defect filled with the new bone onthe PCL-tissue surface, and no delayed inflammatory reaction appeared. The average bone mineral density was greater in the experimental group than that in the control group, and the difference had statistical significance(P＜0.05). Theresults of 99mTc-MDP bone scanning and γ-display ratio showed that thenuclide uptake was more in the PCL group than that in the control group. The SEM result proved that the new compact bone formed on the PCL migrating surface as the PCL degraded gradually，but the collagen fiber sheathe formed around the hydroxyapatitein the control group. Conclusion PCL possesses good biocompatibility and high bone inductive potentiality, it can be used to repair bone defect.