• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.1
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• pp.1-14
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• 2000

The purpose of this study was to evaluate the efficacy of adding autogenous bone to the toothash-plaster mixture in the healing process of bone. Full-thickness round osseous defects with the diameter of 20mm were made at the calvarial bone of adult dogs (n=19) bilaterally, which were thought to be critical size defect. The right defects were repaired with the toothash-plaster mixture plus autogenous bone (compressed volume 0.3cc) and the left defects with only toothash-plaster mixture. At 2-, 4-, 8-, 12- and 20- week after implantation, dogs were sacrificed and evaluated the osseous healing of bony defects clinically, radiographically, and microscopically. The results were as follows; 1. At the clinical observation, the wound healed very well without any problem except severe swelling in the early period after operation. Slight depression was recognized at the both sides when the portions of cranial defect were palpated. 2. There were statistically significant differences between toothash-plaster mixture groups and autogenous bone added groups at the same period, and among the groups in the bone density of the digital radiograms (P<0.001). There was a tendency that bone density was increasing with time. 3. In light microscopic examination, new bone formation was more active in the autogenous bone added groups than toothash-plaster mixture groups at the early period after implantation but there is little difference at 20-week after implantation. 4. In fluorescent microscopic examination, the fluorescent band could be observed at the area of active bone formation and the band was more distinct in the autogenous bone added groups then toothash-plaster mixture groups. 5. In transmitted electron microscopic examination, organelles such as rER, Golgi complex and secretory granule and osteoblast were observed. In summary higher volume ratio of autogenous bone is needed to improve the bone healing in that there is little difference between toothash-plaster mixture group and autogenous bone added group at the 20-week after implantation in spite of new bone formation was more active in the autogenous bone added groups than toothash-plaster mixture groups at the early period after operation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.1
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• pp.45-54
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• 1997

The purpose of this investigation was to determine the biomechanical property of calvarial defects reconstructed using toothash, plaster and tooth-plaster mixture. Full-thickness bony defects were made on the rat calvaria with size of $10mm{\times}10mm$. Group 1 was filled with toothash only, group 2 : toothash-plaster mixture, and group 3 : plaster only. The defects were allowed to heal for 12 and 20 weeks before killing the animals. Light microscopic examinations vas taken after 12 week after operation. The hardness was evaluated for test of mechanical property. The following results were obtained : 1. In light microscopic examination 12 week after operation, there were no inflammatory and foreign body reaction. Implanted particles were resorbed gradually or united directly with newly formed bone. 2. In hardness test, the hardness of newly formed bone was lower than that of normal bone and there was significant difference(P<0.01). The site of new bone formation has enough hardness to resist the mechanical stress. These results suggest that toothash and plaster are biocompatible and osteoconductive material.

• The Journal of the Korean dental association
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• v.36 no.4 s.347
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• pp.289-295
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• 1998

Toothash and Plaster of Paris(Calcium sulfate) mixture have been studied for development of new biomaterial since 1992. I have performed the experimental and clinical study for evaluation of biocompatibility and possibility of bony defect reconstruction and clinical application. These materials are biocompatible, osteoconductive and resorbable. Main component of toothash is hydroxylapatite. In the future, I will perform the systematic construction of material and additional research.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.1
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• pp.26-32
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• 1996

This study was performed to determine the ideal mixing ratio of toothash and plaster of Paris. The histopathologic and histomorphometric study of bone response of five implant materials, toothash(Group A), tooth and plaster mixture, mixing ratio due to weight 2 : 1(Group B), 3 : 1(Group C), 4 : 1(Group D), and plaster Paris(Group E), were performed in rat calvarial defect. No sign of extensive inflammatory reaction was defected. Newly-formed bony ingrowth occurred in all experimental groups except for group E at 12 weeks after operation. Bone was deposited directly on the surface of implant materials. The highest rate of direct bony union between implant material and newly-formed bone occurred with the group B, followed group C, D, and A.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.1
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• pp.15-24
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• 2001

The purpose of this study is to evaluate the tissue response in applying of various bone substitutes included toothash-plaster mixture, resorbable hydroxylapatite (HA) and demineralized freeze-dried bone and to show the clinical usefulness of toothash-plaster mixture for the repair of craniomaxillofacial bone defect. For this experiment, 100 Sprague-Dawley rats weighing 200gm or more were used. There were four experimental groups: group I, toothash-plaster mixture; group II, demineralized freeze-dried bone; group III, resorbable HA; and group IV, control group. A full thickness, round bone defect measuring 10mm in diameter was created in the midcranium, and the substitutes cited above were embedded in the experimental rats based on their group assignment. Blood clot was filled in the rats assigned to the control group. Experimental rats were sacrificed on the 1st, 3rd, 5th, 8th, 12th and 24th week after implantation and stained with the hematoxylineosin, Masson's Trichrome, using Van Gieson's stain method, and were examined under light microscope. The results were as follows: 1. In all the groups, prominent inflammatory reaction and the infiltration of multinucleated giant cells were noted during the early stage. Gradual healing decreased this reaction. 2. Among the rats in the experimental group II, which were given demineralized freeze-dried bone implants, active formation of new bone traveculae manifested. Chondroid tissues appeared, and it was suggested that the defect was filled with newly formed bone by virtue of osteoinductive activity. On the 12th week after the experiments, most of the defect was filled with newly formed bone trabeculae. 3. In experimental groups I and III, it was noted that HA manifested a healing process similar to that characterized by the toothash-plaster mixture, but inflammatory reaction was more prominent in experimental group I. Active osteoblasts were observed along the periphery of osteoid tissues, while newly formed bone trabeculae appeared adjacent to the implanted materials three weeks later. Formation increased to the extent that newly formed bone trabeculae fused directly with the host bone. Increase in new bone ingrowth into the filling materials was revealed by both experimental groups. 4. In the control group, new bone formation adjacent to the host bone was observed, but most of the defect was filled with mature connective tissue 24 weeks after the experiments.

• 대한치주과학회:학술대회논문집
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• 2005.11a
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• pp.66-67
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• 2005

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.2
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• pp.142-149
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• 2008

The purpose of this study was to evaluate histomorphometrically a toothash - plaster of Paris mixture associated with collagen membrane ($Bio-Gide^{(R)}$), regarding new bone formation in the peri-implantitis defects in dogs. Three mandibular molars were removed from 1-year-old mongrel dogs. After 2 months of healing, 2 titanium implants with sandblasted with large grit and acid etched (SLA) surface were installed in each side of the mandible. Experimental peri-implantitis was induced with ligatures after successful osseointegration. Ligatures were removed after identification of bone defect beneath the level of 5th thread of fixture on radiographic image. The mucoperiosteal flaps were elevated and the contaminated fixtures were treated with chlorhexidine and saline. The bone defects were assigned to one of the following treatments: no guided bone regeneration (GBR) procedure (group 1), GBR with Bio-$Oss^{(R)}$ and Bio-$Gide^{(R)}$ (group 2), or GBR with toothash - plaster of Paris mixture (TPM) and Bio-$Gide^{(R)}$ (group 3). The dogs were sacrificed after 8 or 16 months. The mean percentages of new bone formation within the limits of the 5 most coronal threads were $17.83{\pm}10.69$ (8 weeks) and $20.13{\pm}13.65$ (16 weeks) in group 1, $34.25{\pm}13.32$ (8 weeks) and $36.33{\pm}14.21$ (16 weeks) in group 2, and $46.33{\pm}18.39$ (8 weeks) and $48.00{\pm}17.78$ (16 weeks) in group 3, respectively. The present study confirmed statistically considerable new bone formation within the threads in group 3 compared with group 1 at 8 and 16 weeks (P<0.05). Although, data analysis did not reveal significant differences between group 2 and 3, the latter showed better results during the period of 8 or 16 weeks. Our findings support the effectiveness of TPM as a GBR material in the treatment of peri-implantitis bone defect.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.253-260
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• 1996

The purpose of this investigation was to determine the possibility of clinical use of toothash-plaster block implant material with ratio of 2 : 1 by weight. We made 1cm diameter round partial thickness defect at both sides of calvaria. Right side was implanted with block and left side was not implanted as a control site. The following results were obtained : 1. In gross examinations, the implanted site had a hardness on palpation and the margin with host bone was not identified clearly at 12 weeks after operation. But control site contained the fibrous tissue. 2. In the light microscopic examinations, most of the implanted sites were repaired by newly-formed bone at 12 weeks postoperatively. 3. At 8 weeks postoperatively, the implanted particles were divided into small granules and the amount was decreased gradually. Some remained particles were united directly with newly-formed bone. But the implanted particles still remained partly at 24 weeks postoperatively.