• Journal of Periodontal and Implant Science
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• v.50 no.4
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• pp.226-237
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• 2020

Purpose: This study was conducted to assess the efficacy of prophylactic gingival grafting in the mandibular anterior labial area for preventing orthodontically induced gingival recession. Methods: Eight mongrel dogs received gingival graft surgery at the first (I1) and third (I3) mandibular incisors on both sides based on the following group allocation: AT group (autogenous connective tissue graft on I1), AT-control group (contralateral side in the AT group), CM group (xenogeneic cross-linked collagen matrix graft on I3) and CM-control group (contralateral side in the CM group). At 4 weeks after surgery, 6 incisors were splinted and proclined for 4 weeks, followed by 16 weeks of retention. At 24 weeks after surgery, casts were made and compared with those made before surgery, and radiographic and histomorphometric analyses were performed. Results: Despite the proclination of the incisal tip (by approximately 3 mm), labial gingival recession did not occur. The labial gingiva was thicker in the AT group (1.85±0.50 mm vs. 1.76±0.45 mm, P>0.05) and CM group (1.90±0.33 mm vs. 1.79±0.20 mm, P>0.05) than in their respective control groups. Conclusions: The level of the labial gingival margin did not change following labial proclination of incisors in dogs. Both the AT and CM groups showed enhanced gingival thickness.

• Journal of Periodontal and Implant Science
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• v.30 no.1
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• pp.91-104
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• 2000

Many synthetic bone materials have been studied for their potential of regenerative effects in periodontal tissue. Safflower seeds have been traditionally used as a drug for the treatment of fracture and blood stasis in oriental medicines. The purpose of this study was to assess and compare the osseous responses in rat calvarial defects between bone substitutes such as calcium carbonate and bovine-derived hydroxyapatite and feeding of safflower seeds. The calvarial defects were made with 8 mm trephine bur in 24 Sprague-Dawley rats. Two graft materials were implanted in each experimental groups, whereas the control and safflower seed feeding groups were sutured without any other treatment. And then the rats of safflower seed feeding group were supplied with 3 g/day of safflower seeds. Each group was sacrificed at 4 weeks and 8 weeks. To study a histopathology related to bone healing and regeneration, Goldner's Masson Trichrome stain was done at each weeks. The tissue response was evaluated under light microscope. There were more osteoblastic activity, new bone formation, dense bony connective tissues in bovine-derived hydroxyapatite group compared to other groups at 8 weeks. The osseous defect area of safflower seed feeding group was filled with prominent fibrous tissues, where less inflammatory infiltration and new capillary proliferation. In the early phase of bone healing, safflower seed feeding reduces the inflammatory response and promotes the proliferation of connective tissue. These results suggest that natural bovine-derived HA and safflower seed feeding could enhance the regenerative potential in periodontal defects.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.20-42
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• 1998

The present study was designed to understand the basic principles of the laser system and to assess the optimal coditions of the Nd:YAG laser irradiation system in order to expand the use of the laser system in the dental field. The laser system used in this study was a pulsed-wave output type and the power level is 9 watts. The incisors of developing rats were irradiated with the laser system explained above for 0.5, 1, and 2 seconds giving energy density 71, 167, and 215 J/$cm^2$ respectively. The rats were sacrificed just after irradiation or 10 minutes and 10 days after irradiation. The specimens were examined with the stereoscope, light microscope and transmission electron microscope. The results are as follows: 1. The tissue removal efficiency (depth of the cavity formed) is increased with the energy density after Nd:YAG laser irradiation. 2. The carbonized area is increased with the energy density. Cracks and melted appearance are seen in all kinds of the energy densities. 3. The lacunae in the damaged alveolar bone by the laser irradiation were empty, while those in the newly formed bone were occupied with the osteocytes. The damaged alveolar bone was repaired by the osteoblasts and macrophages on the periphery of the bone matrix. 4. The damaged enamel was replaced by the loose connective tissues showing many kinds of cells. The ameloblasts were differntiated on the replaced loose connective tissue. 5. The damaged dentin was repaired by the irregular dentin formed by the odontoblasts differentiated from the mesenchymal cells migrated from the pulp core.

• Applied Microscopy
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• v.13 no.1
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• pp.41-47
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• 1983

A Scanning electron microscope which can obtain additional information not readily available with either the light or transmission electron microscope was used to study the mast cell shape and its granules in normal mammal tissue(rat mesentery, stomach and mouse stomach) by fretting cut using liquid nitrogen. The results showed that rat mesentery and mouse stomach mast cell surfaces had no ridges and microvilli, but revealed several microvilli projecting into the surrounding connective tissue in the rat stomach mast cell. The shape of the mast cell varied from discoid(in the rat mesenteric mast cell) to ellipsoid (rat and mouse stomach), ranging from 7.5 to $10{\mu}m$ in diameter. The shape of the nucleus was ellipsoid and nucleic membrane was adherent to the outer surface of the granules. The granules, approximately 0.2 to $0.9{\mu}m$ in diameter, were various shapes. Frequently, rounded protrusions of cytoplasmic granules could be discerned under the cell membrane. Many small granules were seen in the cytoplasm.

• Journal of Korean Medicine for Obesity Research
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• v.5 no.1
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• pp.133-140
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• 2005

The prevalence of obesity at all ages in increasing epidemically worldwide. There were many study of an indirect method on fat mass measurement in obesity, but were few study to determine the possible relationships between local fat deposition and health-related fitness parameters in overweight and obesity. We has reviewed on the somatotype characteristics, ideal posture and biomechanics, and adipose tissue of connective tissue, myofacia continuity. We consider that these unique 'whole systems' view is of vital importance to understanding the role of adipose tissue in musculoskeletal system and to application of body shape correction program.

• Journal of Korean Physical Therapy Science
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• v.1 no.2
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• pp.333-343
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• 1994

This study was performed to assess the efficacy of electrical stimulation for healing of wound in injured tissue, and to provide a baseline for electrical stimulation in the treatment. Although the specific mechanism by electrical stimulation which may promote injured tissue to heal is not known, generally many hypothesis exist such as bactericidal effect, enhanced circulation, stimulation of cellular biosynthesis and replication, and attraction of connective tissues and inflammatory cells The results of this study are as follows : 1. The healing of skin wound was facilitated by electrical stimulation 2. The capacity of collagen synthesis was significantly accelerated by electrical stimulation 3. The application of electrical stimulation to injured tissue may be helpful in augmenting the rate of wound contracture

• Korean Journal of Veterinary Research
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• v.10 no.1
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• pp.33-38
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• 1970

1. Hepatic ascariasis represented by milk spots on the liver surface was found in 475(31.7%) out of 1,500 pigs. 2. For histopathological studies, 170 cases were collected at random from the milk spotted liver From these cases ascaris larva was found in 14 cases(8.2%). 3. Grossly, the occurrence of milk spots was not confined to any particular lobes of the liver. The lesions, however, were more frequently found in the diaphragmatic surface than in the visceral surface. The extent of the spots was limited to the subcapsular region and the deeper tissue was not affected. 4. Histologically, hemorrhage and eosinophilic infiltration were observed in the area invaded by the larva. The increase of connective tissue followed by a form of chronic lymphocytic hepatitis was observed at the late stage of infection. There was numerous eosinophilic infiltration around the larva trapped in the liver tissue. Consequently, encapsulation of the larva was followed by organization and calcification.

• Journal of Yeungnam Medical Science
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• v.26 no.1
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• pp.1-14
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• 2009

Human bone marrow-derived mesenchymal stem cells (MSCs) are a rare population of undifferentiated cells that have the capacity of self renewal and the ability to differentiate into mesodermal phenotypes, including osteocytes, chondrocytes, and adipocytes in vitro. Recently, MSCs have been shown to reside within the connective tissue of most organs, and their surface phenotype has been well analyzed. Many reports showed that transplanted MSCs enhanced regeneration as well as functional improvement of damaged organs and tissues. The wide differentiation plasticity of MSCs was expected to contribute to their demonstrated efficacy in a wide variety of experimental animal models and in human clinical trials. However, new findings suggest that the ability of MSCs to alter the tissue microenvironment via secretion of soluble factors may contribute more significantly than their capacity for differentiation in tissue repair. This review describes what is known about the cellular characteristics and differentiation potential of MSCs, which represent a promising stem cell population for further applications in regenerative medicine.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.48 no.5
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• pp.315-317
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• 2022

Osseous metaplasia is defined as the formation of lamellar bone inside soft tissue structures where bone normally does not exist. It results from the transformation of non-osseous connective tissue into mature bone. This condition is rare in the oral and maxillofacial region. We report a case of osseous metaplasia of the maxilla, a rare benign tumor in an uncommon region. A 60-year-old male patient visited our clinic complaining of foreign body sensation and asymptomatic swelling on the right palatal side. However, he did not experience pain and reported no local trauma that he could remember. Intra-oral examination revealed an exophytic lesion on the right palatal portion. On computed tomography, there was a round hard-tissue mass approximately 2 cm in diameter on the right palate area. The mass was biopsied and diagnosed as an osseous metaplasia. We review the clinical, radiographic, and histologic features and common causes of osseous metaplasia and report a rare case of osseous metaplasia of the palate.

• Journal of Periodontal and Implant Science
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• v.31 no.2
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• pp.317-332
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• 2001

The purpose of this study was to investigate effects of the natural coral(NC) and the hydroxyapatite/calcium sulfate hemihydrate(HA/CS) on an early stages of wound healing in the rat periodontal fenestration defects. In this experiment, twelve male rats(Mean : 520g in BW) aged 8 to 9 months were used. Experimental periodontal fenestration defects were surgically created with tapered fissure bur at the buccal surface of the left mandibular 1st, 2nd molars. The buccal aspects of molar roots were carefully denuded of their periodontal ligament through a bony window created in the left mandibles of rats under general anesthesia. Each experimental periodontal fenestration defect was grafted with natural coral and HA/CS, randomly. An area without bone graft was assigned for negative control group. At 10,35 days, rats were serially sacrificed via intracardiac perfusion with 2.5% glutaraldehyde and specimens were processed with Hematoxylin-Eosin stain for light microscopic evaluation. The results of this study were as follows : 1. The defect areas were filled with dense connective tissues at 10 days in control group. But in the test(NC, HA/CS)groups, the connective tissues around graft materials were formed more loosely and the response of inflammation by graft materials itself was not found. 2. The defect areas were filled with new osteoid tissues and new cementum was not formed on the cut root surface at 35 days in the control group. 3. New osteoid tissue formation was more prominent at 35 days in control than test groups. 4. The NC and HA/CS particles were encapsulated by loose connective tissues at 10 days and by dense connective tissues at 35 days, respectively. 5. In the test groups, resorption of graft particles was not found through the experimental time. From the above results, natural coral and hydroxyapatite/calcium sulfate hemihydrate may be biocompatible and osteoconductive and have a weak adverse reaction to the periodontal tissues.