• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권2호
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• pp.50-56
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• 2014

Purpose: This study examined the osteoinductive activity of demineralized human dentin matrix for nude mice. Methods: Twenty healthy nude mice weighing about 15 to 20 g were used for study. Demineralized human dentin matrix was prepared and implanted into the dorsal portion of nude mice (subcutaneous), which were sacrificed at two, four, and eight weeks after demineralized dentin matrix grafting and evaluated histologically by H&E and Masson trichrome staining. The specimens were also evaluated histomorphometrically. Results: The demineralized dentin matrix induced bone and cartilage formation independently in soft tissues. Histological examination showed bone-forming cells such as osteoblasts and fibroblasts at two, four, and eight weeks. Conclusion: These results suggest that demineralized human dentin matrix has osteoinductive ability, and is a good alternative to autogenous bone graft materials.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권4호
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• pp.350-364
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• 1995

As early as 1889, treatment of ostemyelitis was reported using xenogeneic demineralized bone. In 1965, Urist discovered that demineralized long bone fragment, even when implanted in nonskeletal tissue, would stimulate osteogenesis. The clinical use of demineralized bone of Oral and Maxillofacial surgery is not new. The demineralized bone implants were used for 1) interposition within osteotomy gaps, cystic detects, alveolar clefts ; 2) augmentation, over intact bone surfaces ; 3) construction of new bone within soft tissue. Demineralized bone grafts invokes a induced osteogenesis which is the transformation of host cells into osteoblasts. Demineralized bone has identified several factors that modulate the osteogeneic response : sterilization method, recipient age, particle size etc. Especially, pulverization of bone matrix may enhance its osteoinductive properties, to allow rapid, efficient bridging of large defects. the purpose of the present report was to describe the potential efficacy of demineralized allogeneic bone powder of skull of rabbits as a particle size ; 212 ${\mu}m$, 710 ${\mu}m$, 1 mm each other. Microscopic finding in our experimental studies shown that 710 ${\mu}m$ demineralized bone powder is the most potent osteogenic response, and then 212 ${\mu}m$, 1 mm size. Densitometric analysis shown that density of all group was continue to increase until 4 weeks after operation, and then continue to decrease.

• Restorative Dentistry and Endodontics
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• 제39권3호
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• pp.155-163
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• 2014

Objectives: Light-curing of resin-based materials (RBMs) increases the pulp chamber temperature, with detrimental effects on the vital pulp. This in vitro study compared the temperature rise under demineralized human tooth dentin during light-curing and the degrees of conversion (DCs) of three different RBMs using quartz tungsten halogen (QTH) and light-emitting diode (LED) units (LCUs). Materials and Methods: Demineralized and non-demineralized dentin disks were prepared from 120 extracted human mandibular molars. The temperature rise under the dentin disks (n = 12) during the light-curing of three RBMs, i.e. an Ormocer-based composite resin (Ceram. X, Dentsply DeTrey), a low-shrinkage silorane-based composite (Filtek P90, 3M ESPE), and a giomer (Beautifil II, Shofu GmbH), was measured with a K-type thermocouple wire. The DCs of the materials were investigated using Fourier transform infrared spectroscopy. Results: The temperature rise under the demineralized dentin disks was higher than that under the non-demineralized dentin disks during the polymerization of all restorative materials (p < 0.05). Filtek P90 induced higher temperature rise during polymerization than Ceram.X and Beautifil II under demineralized dentin (p < 0.05). The temperature rise under demineralized dentin during Filtek P90 polymerization exceeded the threshold value ($5.5^{\circ}C$), with no significant differences between the DCs of the test materials (p > 0.05). Conclusions: Although there were no significant differences in the DCs, the temperature rise under demineralized dentin disks for the silorane-based composite was higher than that for dimethacrylate-based restorative materials, particularly with QTH LCU.

• Journal of Periodontal and Implant Science
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• 제26권4호
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• pp.889-905
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• 1996

It is known that growth factors function as potent biologic mediators regulating numerous activities of wound healing via cell proliferation, migration and extracellular matrix formation and they also promote periodontal regeneration. But, method of growth factor application is controversial yet. So purpose of this study is to evaluate the effect of demineralized root surface as one of method of growth factor application. The ginigival fibroblasts were primary cultured and fifth or sixth subpassages were used in these experiments. In first experiment, root surface blocks demineralized with 100mg/ml tetracycline for 5 minutes and pH 1 citric acid for 3 minutes(experimental groups) and nonteminerilized root surface blocks (control groups) were placed in 100ng/ml PDGF-BB for 5 minutes. Then the cells were seeded on each root surface blocks and cultured for 6, 24, 48, 72 hours. In second experiment, root surface blocks deminerilized with tetracycline and citric acid and nondemineralized root surface blocks were placed in 200ng/ml PDGF-BB for 5 minutes and another non-demineralized root surfcae blocks were placed in DMEM without PDGF-BB. At 1, 2, 4, 6, 8 days, the cells were seeded in 24-well plate and using of each eluent, cultured for 72 hours. The results of the four determinants were presented as mean and S.D.. The results were as follows : The attachment and proliferation of human gingival fibroblast on root surface were more increased when PDGF-BB was applicated on root surfrace demineralized with tetracycline or citric acid than non-demineralized root surface. And, in comparision tetracycline with citric acid, there were more attachment and proliferation of human gingival fibroblast on root surface demineralized with tetracycline than citric acid, and proliferation of human gingival fibroblast on demineralized root surface was increased time dependently 1 day to 3 days. In second experiment using eluent, proliferation of human gingival fibroblast was more increased to 6 days when human gingival fibroblast was cultured in eluent that PDGF-BB was applicated on demineralized root surface than two control groups, and degree of proliferation was decreased time dependently 1 day to 6 days. Proliferation of human gingival fibroblast cultured in eluent without PDGF-BB was constant 1 day to 6 days. After 6 days, degree of proliferation of human gingival fibroblast was similar in four groups. This means that release duration of PDGF-BB from demineralized root surface is 6 days. And in comparision tetracycline with citric acid, there was more proliferation of human gingival fibroblast in tetracycline-treated group than citric acid. In conclusion, demineralized root surface as primary site for PDGF-BB application, especially demineralized with tetracycline has important roles in attachment and proliferation of human gingival fibroblast, and may be useful clinical applications in periodontal regenerative procedures.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권2호
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• pp.137-152
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• 1995

This study was designed to evaluate the bone formation capability of the bone substitute when compared with autogenic bone, freeze-dried demineralized allogeneic bone and bioglass into parietal bone of the rats. We made the parietal bone defects in $7{\times}7mm$ size on rats and has performed the bone graft in each experimental groups. Postoperatively 1, 2, 4, 6, 8, weeks, each specimen stained with H & E, Masson's trichrome methods. We evaluated the osteogensis capability in each groups. The result were as follow : 1. Inflammatory cell infiltration approached at 1 week and disappeared at 4 weeks in all experimental group, expecially severe in freeze-dried demineralized allogeneic bone group. 2. New capillry proliferation was increased in autogeneic bone graft group than any other groups and was increased till 2 weeks and decreased in freeze-dried demineralized allogeneic bone group and was few in bioglass group. 3. Osteoblastic activity increased in autogeneic bone and freeze-dried demineralized allogeneic bone groups till 4 weeks, and decreased in 6 weeks which no difference between these groups. But, few occurred in bioglass group till 6 weeks. 4. Initial osteoclastic activity was prominent in freeze-dried demineralized allogeneic bone group and few in autogeneic bone group. 5. New bone formation bega at 1 week in autograft and freeze-dried demineralized allogenic bone groups, but, mild new bone formation at 8 weeks in bioglass.

• Journal of Periodontal and Implant Science
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• 제25권2호
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• pp.341-356
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• 1995

The purpose of this study was to evaluate the effect of demineralized freeze dried bone and demineralized bone gel with guided tissue regeneration treatment around titanium implants with dehisced bony defects and also evaluate space maintaining capacity of demineralized bone gel type and DFDB powder type under e-PTFE membrane. In 3 Beagle dogs, mandibular premolar was extracted and four peri-implant osteotomies were formed for dehiscence. After insertion of implants, the four peri-implant defects were treated as follows. 1) In control group. no graft material and barrier membrane were applied. 2) In experimental group.1, the site was covered only with the e-PTFE membrane. 3) In experimental group 2,received DFDB powder and covered by the e-PTFE membrane. 4) In experimental group 3, demineralized bone gel and e-PTFE membrane were used. By random selection, animals were sacrificed at 4, 8, 12 weeks. The block sectioned specimens were prepared for decalcified histologic evaluation(hematoxylin and eosin staining) and undecalcified histologic evahiation(Von Kossa's and toluidine blue staining) with light microscopy. The results of this study were as follows. 1) In control group, there was a little new bone formation and connective tissue was completely filled in the defect area. 2) Experimental group 1 showed lesser quantity of bone formation as compared to the bone grafted group. Thin vertical growth of new bone formation around implant fixture was shown. 3) Experimental group 2 showed thick bucco-lingual growth of new bone formation and grafted bone particles were almost resorbed in 12 week group. 4) In experimental group 3, most grafted bone particles were not resorbed in 12 week group and thick bucco-lingual bone formation was shown in dehisced defect base area. 5) There was no remarkable differences in space making capacity and new bone formation procedure between demineralized freeze-dried bone powder type and demineralized bone gel type.

• 치위생과학회지
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• 제23권3호
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• pp.236-244
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• 2023

Background: The size of the tooth whitening market and toothpaste market is increasing worldwide. The purpose of this in vitro study is to confirm and compare the coffee stain removal effects of commercial whitening toothpaste in sound and demineralized teeth, respectively. Methods: A total of 112 flat permanent bovine teeth specimens were manufactured. Half of the surface of the specimen was coated with an acid-resistant varnish and deposited in an artificial demineralizing solution for 65 hours. The varnish applied to half of the specimen was removed and deposited in a coffee solution for 96 hours to induce coloring. Two control and five experimental group toothpastes for teeth whitening were selected and the main components were investigated. Toothbrushing was performed 50, 100, and 150 times for each toothpaste group. A total of four images were obtained: before the start and after 50, 100, and 150 times of brushing to obtain the lightness (L^*) values of the sound and the demineralized tooth surfaces. The difference in the average value between toothpaste groups at each treatment period was analyzed by one-way ANOVA. The difference in the L^* average value according to the number of the brushing was analyzed by repeated measure ANOVA. Results: All toothpastes in the seven groups contained abrasive agents and had different ingredients for each product. Compared to before brushing, the L^* value changed significantly in all toothpaste groups after brushing 50 times (p<0.05). This was common in both the sound and demineralized teeth surfaces. Demineralized teeth had significantly lower L^* values at all brushing times than that in sound teeth (p<0.05). Conclusion: The effect of whitening teeth was different for each toothpaste. Demineralized teeth were more likely to cause coloration than sound teeth, and the coloration was not removed well.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제14권3호
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• pp.245-253
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• 1992

To evaluate the tissue response of demineralized and undimineralized xenogeneic bone-martrix graft in extraskeletal site, we prepared human bone as a implant matrix, and outbred mouse as a recipient. Before clinical application of bank bone of human in Wonkwang university, we should confirm the allogeneic bone grafts us a biologically useful bone graft substitutes, obtanined from the patients receiving oral and maxillofacial surgery. The clinical evaluation and histologic studies showed that both (demineralized and undemineralized) xenogeneic bone matrix grafts were not rejected and that they seemed to stimulate new bone formation at the transplanation site. Undemineralized xenogeneic bone marb6 grafts showed minimal bone induction and gradual demineralization with slow resorption and showed that the differentiation of cells showing fibroblastic activity adjacent to the sop tissue were slowly and less frequently than demineralized bone. Characteristical differences between the demineralized and undemineralized matrix were the appearance of foreign body giant cells (multinucleated giant cells) and the evidence of sloe resorption in undemineralized bone matrix.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권3호
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• pp.253-263
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• 1995

Microsurgical vascularized bone transfer has the disadvantages of limitation of available donor sites, loss of donor function, and the possibility of donor site defects or deformity. To overcome these shortage of current microsurgical tissue transfer, the method of creating the neovascularized free flap has been introduced. Potentially, this technique must be an innovation in providing the free vascularized bone grafts that are not limited by natural vascular anatomy. But, as could be imagined technique resulted in unavoidable donor bone defect and additional operation for harvesting the autologous bone. The purpose of this study was to evaluate the efficacy of demineralized allogeneic bone as a possible substitute for autologous bone in fabricating the neo-osseous flap. By histologic, microangiographic and radioisotope method, the viability and vascularity of neo-osseous flap, which has been fabricated using allogeneic bone or autologous bone, was assessed in rat model. After 6 weeks, demineralized allogeneic bone showed consistent bone formation and neovascularization. The clinical and microscopic findings of demineralized allogeneic bone group were inferior to those of autogenous bone with regard to bone regeneration. The amount of bone blood floow per dry weight of demineralized allogeneic bone group was significantly higher than that of autogenous bone, even higher that of control intact iliac bone. In conclusion, findings supported that allogeneic bone could be the potential substitute for autologous bone source in creating a prefabricated neo-osseous flap.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권4호
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• pp.269-278
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• 2021

Objectives: The purpose of this animal research was to compare bone regeneration in augmented rabbit maxillary sinuses treated with demineralized particulate human-tooth graft and anorganic bovine bone by immunohistochemical analysis. Materials and Methods: Piezoelectric bilateral sinus augmentation was performed in eight adult rabbits. In the control group, anorganic bovine was grafted in the maxillary sinus following elevation of the sinus membrane. In the experimental group, demineralized human particulate tooth bone was grafted in the sinus. Bone regeneration in augmented sinuses was evaluated by immunohistochemical analysis using various markers of osteoprogenitor cells. Results: The number of bromodeoxyuridine-labeled cells was significantly higher in the experimental group than in the control group at eight weeks. The immunoreactivity of proliferating-cell nuclear antigen was increased slightly in the experimental group relative to the control group at eight weeks. Other bone markers were expressed equally in the two groups. Conclusion: In the rabbit maxillary sinus, higher osteoinduction was correlated with demineralized human particulate tooth bone grafting than with anorganic bovine grafting.