【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 investigate the clinical application and complicationof the lyophilized small-segment allogeneic bone used in repairing bone defectscaused by benign bone tumor and tumor-like lesions after resection and curettage. Methods From December 1999 to December 2005, 230 patients (156 males, 74 females; age, 5-56years, averaged 32.8 years), who had bone defects caused by benign bone tumors and tumor-like lesions after surgical resection and curettage, were treated by the lyophilized small-segment allogeneic bones. The cavities left by the tumor curettage ranged in size from 1.0 cm×0.8 cm to 10.0 cm×2.0 cm, andthe bone defects were about 1.0 to 3.5 cm in diameter after the localized resection of the bones. According to the bone defect degrees, the autogenous nonvascular iliac bone and the bone allograft (0.5-30.0 g) were implanted, followed by the drainage for 2-3 days and the use of antibiotics to prevent infection. The postoperative systemic and local reactions were observed, and the regular X-ray examinations were performed to observe the bone union. ResultsThere was no significant difference in the allergic reactions, such as postoperative temperature, drained amount, and body swelling, between this kind of transplantation and the autogenous bonetransplantation. The wounds in 196 patients were healed by the first intension.The wounds in 34 patients had extravasate. Among them, the wound was healed by changing dressing in 30cases; the wound had delayed healing in 4, including 3 whose wounds were healedby changing dressing for 3-4 weeks,and 1 whose wound was healed by taking out the implants. The follow-up for 6-60 months (average, 38 months) revealed that all the patients had the allograft unions of the bones within 6-18 months after the transplantation, and only 6patients had recurrence of the tumor (3.0%). Evaluated by the Mankin,Komender and WANG Zhiqiang’s standards, 196 (85.22%) patients were satisfied with their outcomes while the other 34 (14.78%) patients were not satisfied. Conclusion The lyophilized small-segment allogeneic bone has a good compatibility and osteogenesis, when it is used in repairing bone defects caused by benign bone tumor and tumor-like lesions after resection and curettage. So, this kind of bone is a good, convenient and safe material for the bone transplantation. The important factors affecting the allograft union are as follows: the mechanical stability in the recipient region, local blood supply, and management of the bone cavity left by resection and curettage of the bone tumor.
OBJECTIVE To investigate a good method for repairing the long bone defect of tibia combined with soft tissue defect. METHODS From 1988-1998, sixteen patients with long bone defect of tibia were admitted. There were 12 males, 4 females and aged from 16 to 45 years. The length of tibia defect ranged from 7 cm to 12 cm, the area of soft tissue defect ranged from 5 cm x 3 cm to 12 cm x 6 cm. Free fibula grafting was adopted in repairing. During operation, the two ends of fibular artery were anastomosised with the anterior tibial artery of the recipient, and the composited fibular flap were transplanted. RESULTS All grafted fibula unioned and the flap survived completely. Followed up for 6 to 111 months, 14 patients acquired the normal function while the other 2 patients received arthrodesis of the tibial-talus joint. In all the 16 patients, the unstable ankle joint could not be observed. CONCLUSION The modified method is characterized by the clear anatomy, the less blood loss and the reduced operation time. Meanwhile, the blood supply of the grafted fibula can be monitored.
Abstract An experiment was carried out to investigate the possibility of the establishment of an osteoblasts bank which could supply osteoblasts in repairing bone defect. Osteoblasts were isolated from thetibial periosteum of eight New-Zealand rabbits and cultured in votro. A bone defect, 1.5cm in length was made in both radii of each of the 8 rabbits. The cultivated osteoblasts, gelfoam as a carrier were randomly implanted into the defects of the radii of rabbits. Accordingly, the contralateral radial defects wereimplanted with gelfoam absorbed with the Hanks solution as control. The healing of bone defects was evaluated by roentgenographic examination at 2, 4, 8 and 12 weeks after operation, respectively. It was shown that the implanted cells had osteogenetic capability and could be possible to promote healing of the bone defects. It was suggested that further study needed to be carried out in this field.
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.
Objective To find an ideal material for repairing bone defect by local implanting simvastatin compounded with poly-lactic acid (PLA) into the radial critical size defects of rabbits, and to observe the reparative effect and type of bone formation induced by simvastatin. Methods Twelve 4-months-old male New Zealand white rabbits (2.3-2.8 kg) with 22 mm radial critical size defects on both sides were randomized into 4 groups (all n=3). Right side and left side of every rabbit were set as controls with each other. The left defects (experimental groups) of groups A, B, and C were implanted with cyl inder-l ike compound scaffolds containing 50, 100, and 200 mg of simvastatin (fixed with 250 mg PLA), or auto-bonegraft as group D, respectively. The right defects of groups A, B, and C were implanted with scaffolds containing only 250 mg PLA. The right defects of group D were left without any treatment. Digital X-ray images of bone defects were taken 8 and 16 weeks after operation, X-ray was scored double bl ind and X-ray pixel value was measured. Animals were euthanized16 weeks postoperatively. CT was appl ied to analyze new bone formation volume in the defects. In addition, orphologicalcharacters of new bones were observed through micro-CT and histology. Results X-ray films showed that the bone defect of each experimental side had much cloud-l ike callus, and the bone stump were not clear 8 weeks after operation; and the cortex in the defect was continuous and the medullary was recanal ized 16 weeks after operation. In control sides, the cortexes were discontinuous and the ends of fractures were sclerified. At 8 and 16 weeks after operation, the X-ray scores, pixel values and the CT volume percentage of new bone in experiment sides were all significantly higher than those in control sides (P lt; 0.05). The X-ray scores of experimental sides in groups C and D were significantly higher than those in groups A and B 8 weeks after operation (P lt; 0.05), and the X-ray scores of experimental sides in groups B and D were significantly higher than those in groups A and C 16 weeks after operation (P lt; 0.05). The X-ray pixel values of experimental sides of group B were significantly higher than those of groups A, C, and D 8 weeks after operation (P lt; 0.05). The new bone formation volume of experimental side of groups B and D was higher than that of groups A and C (P lt; 0.05), and group D was significantly higher than that of group B (P lt; 0.05). Micro-CT showed bone defects of experimental sides of group B had totally healed, with connected medullary cavities and continuous bone cortex, on the contrary bone defects of control sides of group B did not healed completely. Histological observation showed better bone remodeling effects of the experimental sides than control sides, with connected medullary cavities and continuous bone cortex. And the osteogenetic type was endochondral ossification. Conclusion Local implantation of simvastatin can promote repairing rabbit radial critical bone defect, 100 mg is the best dose of repairing the bone defects.
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.
ObjectiveTo investigate the effect of repairing radial bone defect with scaffold material of attapulgite/collagen type I/poly (caprolactone) (ATP/Col I/PCL) in rabbits and the possibility as bone graft substitutes. MethodsATP/Col I/PCL materials were prepared via adding ATP to hexafluoroisopropanol after dissolved Col I/PCL (3∶2), and Col I/PCL materials via dissolving Col I/PCL (3∶2) in hexafluoroisopropanol served as control. The structure of scaffolds was observed under scanning electron microscope (SEM). Twenty-four Japanese white rabbits (male, 2 months old) were used to establish the bilateral radius defect model of 15 mm in length, and randomly divided into group A (6 rabbits, 12 defects), group B (9 rabbits, 18 defects), and group C (9 rabbits, 18 defects); then the Col I/PCL scaffold was implanted in the bone defect area in group B, the ATP/Col I/PCL scaffold in group C, no treatment was done in group A as control. The general condition of rabbits was observed after operation, and bone defect repair was evaluated by X-ray at 4, 8, and 12 weeks. At 12 weeks, the tissue of defect area was harvested for the general, SEM, Micro-CT, histological, and immunohistochemical staining to observe defect repair and material degradation. ResultsSEM observation showed that two kinds of materials were porous structure, ATP/Col I/PCL structure was more dense than Col I/PCL. All animals survived to the end of experiment, and no incision infection occurred during repair process.X-ray films showed that the bone marrow cavity was re-opened in defect area of group C with time, the repair effect was superior to that of groups A and B. At 12 weeks after operation, general observation showed that scaffold material had good fusion with the surrounding tissue in groups B and C, defect was filled with connective tissue in group A. SEM indicated that the surface and pore of the scaffold were covered with a large number of cells and tissues in groups B and C. Micro-CT demonstrated that the new bone volume, bone mineral content, tissue mineral content, and connectivity density of group C were significantly higher than those of groups A and B (P<0.05). The observation of histology and immunohistochemical staining indicated that there were lots of connective tissues in defect area of group A, and ALP, Col I, and OPN were weakly expressed; there were many collagen fibers in scaffold degradation area in group B, and the expression levels of ALP, Col I, and OPN were higher than those of group A; there was few new bone in group C, the degradation rate of the scaffold was slower than that of group B, and the expression of Col I and OPN were enhanced, while ALP was weakened when compared with groups A and B. ConclusionATP/Col I/PCL composite scaffold material can degrade in vivo, and has dense three-dimensional porous structure, good biocompatibility, and high potentiality of bone repair, so it can be used as bone substitute material.
Objective Construction of viable tissue engineered bone is one of the most important research fields in the cl inical appl ication of bone tissue engineering, to investigate the function of nerve factors in bone tissue engineering by celldetection in vitro and construction of neurotization tissue engineered bone in vivo. Methods Fifty-four healthy New Zealandwhite rabbits, male or female, weighing 2-3 kg, were involved in this study. Bone marrow mesenchymal stem cells (BMSCs) from the bone marrow of white rabbits were cultured. The second passage of BMSCs were treated with sensory nerve or motor nerve homogenates, using the LG-DMEM complete medium as control. The prol iferation and osteogenic differentiation of the cells were observed and tested by the MTT assay, alkal ine phosphatase (ALP) stain, and collagen type I immunocytochemistry identification. The osteogenic induced BMSCs were inoculated in β tricalcium phosphate (β-TCP) biomaterial scaffold and cultured for 72 hours, then the β-TCP loaded with seed cells was implanted in the rabbit femur with 15 mm bone and periosteum defects. Fifty-four New Zealand white rabbits were randomly divided into three groups (n=18): sensory nerve bundle (group A) or motor nerve bundle (group B) were transplanted into the side groove of β-TCP scaffold, group C was used as a control without nerve bundle transplantation. X-ray detection was performed at the 4th, 8th, and 12th weeks after operation.
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.