• Journal of Periodontal and Implant Science
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• v.44 no.5
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• pp.242-250
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• 2014

Purpose: This study aimed to evaluate the effects of fibronectin and oxysterol immobilized on machined-surface dental implants for the enhancement of cell attachment and osteogenic differentiation, on peri-implant bone healing in the early healing phase using an experimental model in dogs. Methods: Five types of dental implants were installed at a healed alveolar ridge in five dogs: a machined-surface implant (MI), apatite-coated MI (AMI), fibronectin-loaded AMI (FAMI), oxysterol-loaded AMI (OAMI), and sand-blasted, large-grit, acid-etched surface implant (SLAI). A randomly selected unilateral ridge was observed for 2 weeks, and the contralateral ridge for a 4-week period. Histologic and histometric analyses were performed for the bone-to-implant contact proportion (BIC) and bone density around the dental implant surface. Results: Different bone healing patterns were observed according to the type of implant surface 2 weeks after installation; newly formed bone continuously lined the entire surfaces in specimens of the FAMI and SLAI groups, whereas bony trabecula from adjacent bone tissue appeared with minimal new bone lining onto the surface in the MI, AMI, and OAMI groups. Histometric results revealed a significant reduction in the BIC in MI, AMI, and OAMI compared to SLAI, but FAMI demonstrated a comparable BIC with SLAI. Although both the BIC and bone density increased from a 2- to 4-week healing period, bone density showed no significant difference among any of the experimental and control groups. Conclusions: A fibronectin-coated implant surface designed for cell adhesion could increase contact osteogenesis in the early bone healing phase, but an oxysterol-coated implant surface designed for osteoinductivity could not modify early bone healing around implants in normal bone physiology.

• Journal of Yeungnam Medical Science
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• v.24 no.2
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• pp.262-274
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• 2007

Purpose : Bone morphogenetic proteins (BMPs) play an important role in the formation of cartilage and bone, as well as regulating the growth of chondroblasts and osteoblasts. In this study, we investigated whether recombinant human BMP adenoviruses are available for ex vivo gene therapy, using human fibroblasts and human bone marrow stromal cells in an animal spinal fusion model. Materials and Methods : Human fibroblasts and human bone marrow stromal cells were transduced with recombinant BMP-2 adenovirus (AdBMP-2) or recombinant BMP-7 adenovirus (AdBMP-7), referred to as AdBMP-7/BMSC, AdBMP-2/BMSC, AdBMP-7/HuFb, and AdBMP-2/HuFb. We showed that each cell secreted active BMPs by alkaline phosphatase staining. Since AdBMP-2 or AdBMP-7 tranducing cells were injected into the paravertebral muscle of athymic nude mice, at 4 weeks and 7 weeks, we confirmed that new bone formation occurred by induction of spinal fusion on radiographs and histochemical staining. Results : In the region where the AdBMP-7/BMSC was injected, new bone formation was observed in all cases and spinal fusion was induced in two of these. AdBMP-2/BMSC induced bone formation and spinal fusion occurred among one of five. However, in the region where AdBMP/HuFb was injected, neither bone formation nor spinal fusion was observed. Conclusion : The osteoinductivity of AdBMP-7 was superior to that of AdBMP-2. In addition, the human bone marrow stromal cells were more efficient than the human fibroblasts for bone formation and spinal fusion. Therefore, the results of this study suggest that AdBMP-7/BMSC would be the most useful approach to ex vivo gene therapy for an animal spinal fusion model.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.6
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• pp.244-250
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• 2020

β-Tricalcium phosphate (β-TCP, Ca3(PO4)2) is a kind of biodegradable calcium phosphate ceramics with chemical and mineral compositions similar to those of bone. It is a potential candidate for bone repair surgery. To improve the bioactivity and osteoinductivity of β-TCP, various ions doped calcium phosphate have been studied. Among them, Iron is a trace element and its deficiency in the human body causes various problems. In this study, we investigated the effect of Fe ions on the structural variation, degradation behavior of β-TCP. Fe-doped β-TCP powders were synthesized by the coprecipitation method, and the heat treatment temperature was set at 925 and 1100℃. The structural analysis was carried out by Rietveld refinement using the X-ray diffraction results. Fe ions existed in a different state (Fe2+ or Fe3+) with different heat treatment temperatures, and the substitution sites (Ca-(4) and Ca-(5)) also changed with temperature. The degradation rate was fastest at Fe-doped β-TCP with heated at 1100℃. The cell viability behavior was also enhanced with the substitution of Fe ions. Therefore, the substitution of Fe ion has accelerated the degradation of β-TCP and improved the biocompatibility. It could be more utilized in biomedical devices.

• The Journal of the Korean bone and joint tumor society
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• v.10 no.2
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• pp.96-106
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• 2004

Purpose: To determine the usefulness of limb salvage operation with recycled autogenous bone graft in musculoskeletal malignant tumors. Materials and Methods: Twenty nine cases, who underwent limb salvage operation with recycled autogenous bone graft for the treatment of musculoskeletal malignant tumor between February 1990 and January 2003, were included. There were 18 males and 11 females and the mean age was 33 years (range, 10 to 65 years). The mean follow-up period was 51.8 months (range, 18 to 117 months). The Enneking stage was IIA in 10 cases and IIB in 19 cases. The recycling method of autogenous bone was deep freezing in 6 cases, autoclaving in 11 cases, pasteurization in 7 cases and the composite of autoclaving and vascularized fibular graft in 5 cases. The union of junctional site was evaluated radiologically and the functional results was analyzed by the grading systems of the International Symposium On Limb Salvages (ISOLS). Results: The mean union time was 7.2 months (range, 3 to 15 months). The union took 5.8 months (range, 4 to 8 months) in deep freezing, 9.7 months (range, 6 to 15 months) in autoclaving, 5.9 months (range, 4 to 8 months) in pasteurization, and 5 months (range, 4 to 8 months) in the composite of autoclaving and vascularized fibular graft. The mean functional evaluation percentage was 76.8% (range, 40 to 90%). It was 65.8% (range, 40 to 85%) in deep freezing, 76.6% (range, 40 to 90%) in autoclaving, 81.6% (range, 70 to 90%) in pasteurization, and 83.4% (range, 75 to 90%) in the composite of autoclaving and vascularized fibular graft. There were 6 cases of complications including 1 case of local recurrence, lung metastasis, infection, fracture, respectively and 2 cases of nonunion. Conclusion: The limb salvage operation with recycled autogenous bone graft is a useful treatment method for the musculoskeletal malignant tumors. Particularly, autoclaving is the most reliable sterilization method. The vascularized fibular graft can compensate decreased osteoinductivity and mechanical strength of recycled bone. So, the composite of autoclaving and vascularized bone graft seems to be a favorable treatment method for high grade malignant musculoskeletal tumors.