• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권3호
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• pp.239-252
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• 1995

The present study was aimed to evaluate the effect of demineralized freeze-dried bone (DFDB) and resorbable hydroxyapatite (RHA) on bone formation in the extracted socket. The lower left and right 2nd and 3rd premolar were extracted in adult dogs. The one group was grafted with DFDB into the extracted socket, and the other group grafted with RHA. The extracted socket was sutured without any graft materials as control. The animals were killed on the 1st, 2nd, 4th, and 8th week after the graft for macroscopic and microscopic examination. Results obtained were as follows : 1. Macroscopically, nor infection of the graft site and dislodgement of the grafted material were noted in any animals used. 2. Young trabeculae of osteoid were formed in the socket wall in control group at 2 weeks after the graft. Osteoid tissue was formed in DFDB group at 1 week after graft, and a fine osteoid tissue was grown through the RHA particles in RHA group at 2 weeks graft. 3. The grafted groups showed more rapid bone formation than the control. Between the grafted groups, DFDB group showed more rapid formation than RHA group, DFDB group showed osteoinductive bone formation and RHA group showed osteoconductive bone formation. These results suggest that DFDB and RHA are useful to preserve the alveolar bone and to improve new bone formation by immediate grafting into the extraction sockets.

• Journal of Periodontal and Implant Science
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• 제42권6호
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• pp.237-242
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• 2012

Purpose: The aim of this study was to clinically and radiographically evaluate and compare treatment of intrabony defects with the use of decalcified freeze-dried bone allograft in combination with a calcium sulphate barrier to collagen membrane. Methods: Twelve patients having chronic periodontal disease aged 20 to 50 years and with a probing depth >6 mm were selected. Classification of patient defects into experimental and control groups was made randomly. In the test group, a calcium sulphate barrier membrane, and in control group, a collagen membrane, was used in conjunction with decalcified freeze-dried bone graft in both sides. Ancillary parameters as well as soft tissue parameters along with radiographs were taken at baseline and after 6 months of surgery. Parameters assessed were plaque index, modified gingival index, probing depth, relative attachment level, and location of the gingival margin. A Student's t-test was done for intragroup and a paired t-test for intergroup analysis. Results: Intragroup analysis revealed statistically significant improvement in all the ancillary parameters and soft tissue parameters with no statistically significant difference in intergroup analysis. Conclusions: The study concluded that a calcium sulphate barrier was comparable to collagen membrane in achieving clinical benefits and hence it can be used as an economical alternative to collagen membrane.

• Journal of Periodontal and Implant Science
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• 제42권6호
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• pp.224-230
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• 2012

Purpose: Various bone graft materials have been used for periodontal tissue regeneration. Demineralized freeze-dried bone allograft (DFDBA) is a widely used bone substitute. The current widespread use of DFDBA is based on its potential osteoinductive ability. Due to the lack of verifiable data, the purpose of this study was to assess the osteoinductive activity of different DFDBAs in vitro. Methods: Sarcoma osteogenic (SaOS-2) cells (human osteoblast-like cells) were exposed to 8 mg/mL and 16 mg/mL concentrations of three commercial types of DFDBA: Osseo+, AlloOss, and Cenobone. The effect of these materials on cell proliferation was determined using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. The osteoinductive ability was evaluated using alizarin red staining, and the results were confirmed by evaluating osteogenic gene expression using reverse transcription polymerase chain reaction (RT-PCR). Results: In the SaOS-2 cells, an 8 mg/mL concentration of Osseo+ and Cenobone significantly increased cell proliferation in 48 hours after exposure (P<0.001); however, in these two bone materials, the proliferation of cells was significantly decreased after 48 hours of exposure with a 16 mg/mL concentration (P<0.001). The alizarin red staining results demonstrated that the 16 mg/mL concentration of all three tested DFDBA induced complete morphologic differentiation and mineralized nodule production of the SaOS-2 cells. The RT-PCR results revealed osteopontin gene expression at a 16 mg/mL concentration of all three test groups, but not at an 8 mg/mL concentration. Conclusions: These commercial types of DFDBA are capable of decreasing proliferation and increasing osteogenic differentiation of the SaOS-2 cell line and have osteoinductive activity in vitro.

• 방사선산업학회지
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• 제9권2호
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• pp.63-68
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• 2015

Lyophilized DOTMP kits were prepared using DOTMP, ammonium acetate, and ascorbic acid. The $^{68}Ga$-DOTMP was prepared by incubating the kit dissolved in 0.5 ml of concentrated $^{68}Ga$ using NaCl method and 0.5 ml of DDW, at $100^{\circ}C$ for 7 min. The labeling yield was evaluated by two solvent systems of TLC. 1 MBq of concentrated $^{68}Ga$ was labeled with $0.8{\mu}g$ of DOTMP by high radiolabeling yield (>98%), which was determined by two TLC methods. The composition of the prepared freeze-dried vial is $400{\mu}g$ of DOTMP, 19.27 mg of ammonium acetate and 17.62 mg of ascorbic acid. ~555 MBq of $^{68}Ga$-DOTMP was prepared with excellent radiochemical purity (>98%) and it was stable for 4 hr at room temperature. In conclusion, Freeze-dried DOTMP kits for the convenient preparation of $^{68}Ga$-DOTMP have been developed. Availability of this kit is expected to stimulate the widespread use of $^{68}Ga$-DOTMP in the fields of nuclear medicine.

• 대한치과의사협회지
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• 제32권4호통권299호
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• pp.285-297
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• 1994

• Journal of Periodontal and Implant Science
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• 제27권4호
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• pp.845-866
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• 1997

Several experimental studies showed that the application of small amounts of electric current to bone stimulated osteogenesis at the site of the cathode and suggests that the application of electrical currents to periodontal defects could promote bone and cementum formation. The purpose of this study was to determine the effect of direct microcurrent to the periodontal regeneration of class III furcation defects in dogs. Class III furcation defects were surgically created on the third and the fourth premolars bilaterally in the mandibles of nine mongrel dogs. Experimental periodontitis were induced by placing small cotton pellets into the created defects for 3 weeks. The experimental sites were divided into three groups according to the treatment modalities: Group I-surgical debridement only; Group II-allogenic demineralized freeze dried bone grafting; Group III-allogenic demineralized freeze dried bone grafting and electrical stimulation. For fluorescence microscopic evaluation, calcein, oxytetracycline HCI and alizarin red were injected 2, 4 and 8 weeksfS days prior to sacrifice) after surgery. The animals were sacrificed in the 1st, 2nd, 4th and 8th week after periodontal surgery and the decalcified and undecalcified specimens were prepared for histological and histometrical examination. After the first and the second weeks, gingival recession was more severe in group I than groups II and III. After the fourth and the eighth weeks, there was no difference in the width of junctional epithelium and connective tissue attachment among the three groups, but the width of connective tissue attachment increased in group II at the eighth week, compared to the fourth week. The amount of bone repair in new attachment was significantly greater in group III, compared to groups I and II. New attachment formation was significantly greater in group III, compared to groups I and group II. These results suggest that electrical stimulation using microcurrent generator could be a useful tool for periodontal regenerative therapy in class III furcation defect.

• Journal of Periodontal and Implant Science
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• 제23권3호
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• pp.374-390
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• 1993

Regeneration of periodontal tissue after a loss of attachment due to disease or trauma repesents an important issue in dentistry, and various bone graft materials have been used to regenerated lost periodontal tissue and restore proper fuctions. Among those, allografts have been extensively researched and widely used clinically, since they are known to possess an excellent osteoinduction capability and result in proper topography of alveolar bone. Regeneration of periodontal tissue in supraalveolar defects may be technically difficult. However, a large amount of regeneration has been observed by complete tissue coverage of involved teeth. In this study, supraalveolar defects in adult dogs were treated with periodontal surgery, decalcified freez-dried bone allograft, complete tissue coverage was attained, and effects on repair and regeneration of alveolar bone, cementum and periodontal ligament were studied. Exposure of premolar furcation of adult dogs was attained by removing marginal alveolar bone down to 5mm from CEJ, and root surfaces were planed with curettes. On the left side, defects were treated without any allograft(Control Group). On the right side, a DFDB was used(Experimental Group). In all groups, flaps were coronally positioned and sutured, completely submerging the treated defects. At two weeks, the crown were exposed 2-3mm. Healing progresses were histologically observed after eight weeks and the results were as follows : 1. Distance from CEJ to AJE was : $2.82{\pm}0.66mm$ in the control group, $1.71{\pm}0.51mm$ in experimental group, with significant differences between groups.(P<0.01) 2. Periodontal repair was : $2.18{\pm}0.66mm$ in the control group, $3.29{\pm}0.51mm$ in experimental group, with significant differences between groups.(P<0.01) 3. Connective tissue repair was : $1.43{\pm}0.52mm$ in the control group, $0.76{\pm}0.47mm$ in experimental group, with significant differences between groups.(P<0.01) Orientation of connective tissue fibers in relation to root surfaces was : mostly parallel in the control group, vertical or parallel or irregular in experimental group. 4. The amount of cementum formation was : $1.66{\pm}0.58mm$ in the control group, $2.86{\pm}0.66mm$ in experimental group, with significant differences between groups. 5. The amount of alveolar bone formation was : $0.76{\pm}0.72mm$ in the control group, $2.53{\pm}0.56mm$ in experimental group, with significant differences between groups.(P<0.01)

• Maxillofacial Plastic and Reconstructive Surgery
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• 제15권3호
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• pp.199-210
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• 1993

Many surgeons are on the point of bone excision and reconstruction of the bone defects by autograft. xenograft, and allograft in the treatment of begin and malignant tumors of bone. Of all type of bone grafts, we received the autograft as the best ideal bone graft. Of autogenic bone graft, replantation of excised autogenic bone for reconstructiong the bone defects has been the ideal method until now, but early bone healing reponses and tumor cell devitalization after replantation of excised autogenic bone have not been identified for clinical applications. So, to evaluate bone healing response after replantation in rabbit's calvarial bone, we divided the experimental group into three groups. Group 1 is a fresh autogenous bone group. Group 2 is a deep frozen group. Group 3 is freeze-dried demineralized group. Obtained result were as followed: 1. Inflammatory cell infiltration appeared at I week and disappeared at 4 weeks in all experimental group, Especially, severe inflammatory cell infiltration showed in fresh autogenous bone group at 2 weeks. Group 3 is the least showing group on the point of inflammatory cell infiltration. 2. Osteoblastic activity evenly increased upto 4 weeks and maintained to 6 weeks and decreased after this period, especially osteoblastic activity in group 2 is less than group 1 and group 3. We can't discriminate between osteoblastic activity of group 1 and that of group 3. 3. In new bone formation, group 3 was more active than any other groups at early stage, but there were little differences among three experimental groups at later state. 4. Bone resorption around the grafted bone slightly appeared at 1 week and disappeared at 4 weeks in all experimental groups. We can find the more bone resorption in group 2 at 2 weeks than any other groups. We could suggest, as appears from our results, that freeze-dried deminiralized bone graft is the useful bone graft in the clinical applications of excised autogenic bone.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제15권1호
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• pp.63-79
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• 1993

To repair bony defects with tansplanted bone in the body, fresh autogenous bone is undoubtly, the most effective bone graft for clinical applications. But the demineralized bone has the matrix-induced bone formation which was suggested by Urist in 1965. Many authors assisted that demineralized bone powder induces phenotypic conversion of mesenchymal cells into osteoblasts, with high-density bone formation. The process of inducing differentiated cells becomes osteogenic properties. The purpose of this study was to evaluate the osteoinductive capacity of allogenic freeze-dried demineralized bone block (FDD, $7{\times}7mm$) and to compare FDD with the same sue of deep-frozen allogenic bone(DF), fresh autogenous bone (A) after implantation. The histological and ultrastructural features of tissue responses were examined after 1, 2, 4, 6, 8 weeks implantation of each experimental groups in the operative site of the New Zealand white rabbits. The results were as follows : 1. Inflammatory cell infiltration generally has appeared at 1 week, but reduced at 4 weeks in each group, but most severe in DF group. 2. Osteoblastic activity has increased for 4 weeks, but decreased at 6 weeks in each group and there was no significant difference among experimental groups. 3. New bone formation has begun at 1week, least activations in A groups, and showed the revesal line of bone formation among each group at 6 to 8 weeks. 4. Bone resorption has appeared at 1 week, but disappeared at 4 weeks in both A and DF groups, but more severe in DF than A groups. 5. In ultrastructural changs, the DF group have showed the most remarkable osteoclastic activities among experimental groups. 6. Osteoid or tangled collagen fibrils near the implanted sites were replaced by more mature, lamellated bony trabeculae during bone remodeling. There was little difference among each experimental groups. 7. During the convertion osteoblasts to osteocytes which embedded within the bone matrix, there was organ-less-poor cytoplasm, increased nuclear chromatin, abundant rough endothelial reticulum (RER) in each groups. From the above the findings, the DF group shored more bone resorption and foreign body reaction than FDD and A groups, and FDD group showed more new bone formation or osteoblastic activity than DF and A groups in early stage. There was no significant difference of cellular activities among the FDD DF, and A groups according to the time.

• Journal of Periodontal and Implant Science
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• 제29권3호
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• pp.469-484
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• 1999

The purpose of this study was to evaluate new bone formation following guided bone regeneration by resorbable and nonresorbable membrane. Six adult mongrel dogs were used. The first, second, third, fourth premolars in the mandible of each dog were extracted. Two months after tooth extraction, a buccal dehiscence defect was surgically created on each edentulous area. The experimental sites were divided into three groups according to the treatment modalities ; Group I-a: surgical treatment only ; Group I -b: allogenic decalcified freezed dried bone grafting ; Group II-a : e- PTFE membrane placement only ; Group II-b : allogenic decalcified freezed dried bone grafting and e-PTFE membrane placement ; Group III-a : Vicryl(R) mesh placement only ; Group III-b : allogenic decalcified freezed dried bone grafting and Vicryl(R) mesh placement . The animals were sacrificed at 8 weeks after operation and the specimens were prepared for histologic and histometric examination. The results were as follows : Clinically, all defect sites were healed without exposure of barrier membrane after the eight weeks. In Group I-a, dense connective tissues were impinged in the bony defect area. Well vascularized and fibrous bone marrow indicated that bone formation was still taking place was found. In Group I-b, in areas closer to the periphery, lamellation of the newly formed bone would found. In Group II-a, beneath the e-PTFE membrane a dense layer of connective tissue covering the most external portions of the regenerated tissue was seen. The new bone surfaces were lined with osteoid and osteoblast. In Group II-b, a dense layer of connective tissue covering the most external portions of the regenerated tissue was observed beneath the e-PTFE membrane. A notable amount of alveolar ridge regeneration was seen with new rigdes with well-contoured form. In Group III-a, the new bone surface were lined with osteoid and osteoblast, indicating active bone formation. A clear demarcation could not be noted between the host bone and new bone. In Group III-b, a notable amount of alveolar ridge regeneration was seen with new ridges assuming wellcontoured form. In areas closer to the periphery, lamellation of the newly formed bone would found. As histometric examination, the amount of bone formation was gained from $12.8mm^2$ to $26.3mm^2$. It was significantly greater in group II-b and group III-b compared to other groups(p<0.05) . These results suggest that Vicryl(R) mesh after DFDB grafting used in guided bone regeneration could create and sustain sufficient space for new bone formation.