• Biomedical Science Letters
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• v.6 no.2
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• pp.119-129
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• 2000

The skin is an organ that has many important roles, including protection against infection, regulation of temperature and fluid loss, and sensory function. Injury to the skin, wound repair normally involves: (1) balanced activity of inflammation, (2) the re-epithelial phase and (3) the matrix formation of remodeling phase. Thus, skin wound healing is a finely controlled biological process involving a series of complex cellular interactions. Laser therapy is being implemented with increasing frequency in medicine. Low intensity laser is one that is capable of producing an energy density so low that any biologic alterations are the result of direct irradiation effect, not thermal events. This study was designed to evaluate the efficacy of low intensity laser therapy on skin wound healing in rabbits. A total of 10 male rabbits (New Zealand White Rabbit), age 8 weeks were used. Skin wound were surgically created dorso-lateral on the flank of 10 rabbits (2$\times$2 cm/damage areas). The experimental animals were treated with 5Hz (830 nm wave length) low-intensity laser (MILTA-01 Model) daily for 10 min (1.6 J/$cm^2$) for 12 days. Control animals were sham treated with the laser head. Laser irradiation animals showed a complete remodeling of the epithelial layer, a positive repair of connective tissues, and enhanced the wound closure rate over time as compared to the control animals. Especially, laser irradiation groups improved fibroblast activity, cellular content, granulation tissue formation, and collagen deposition which is resulted in improving the tensile strength of the wound. These findings suggest that laser photostimulation could accelerate healing of open wound in rabbits, and may be benefit in the treatment of open wound, including decubitis ulcers.

• Applied Microscopy
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• v.27 no.1
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• pp.71-86
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• 1997

The regeneration and differentiation of the cutaneous pigment system in the goldfish, Carassius auratus during the wound healing process were studied with high magnification electron microscope. The cutaneous pigment cells of the normal tissues were composed of three kinds of dermal chromatophores-xanthophores, leucoiphores and melanophores. While xanthophores contain two kinds of pigment granules-pterinosomes and carotenoid vesicles, leucophores and melanophores contain amorphous pigment granules (leucosomes) and oval shaped electron dense melanin pigment granules (melanosomes) respectively. After injury, primary wound healing responses being carried out by migration of epidermal cells and hemocytes spreading over the wound surface at the day of wounding. And at the time of primary wound closure, 5 to 7 days after wounding, rER rich cells-presumably common precursors of dermal chromatophores-immigrated into the wound area. First redifferentiated chromatophores appeared 3 weeks after wounding. Pigment granules of the chromatophores were emerged from the cytoplasmic Golgi complex via rough endoplasmic reticulum. Pinocytotic vesicles which associated with accumulation of pigment material, appeared only at the inner surface of the chromatophores adhering to the rER rich cells, characteristically. The differentiation of each chromatophore in addition to integumental wound repair were accomplished within 4 weeks after wounding at most cases, however the total numbers and densities of these repaired chromatophores still primitive state. Moreover, It has been revealed that complete repair of chromatophores at wounded tissues from burns requirs more than 3 months in normal environment.

• Imaging Science in Dentistry
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• v.32 no.1
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• pp.1-10
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• 2002

Purpose: To observe the histopathological changes following irradiation on the wound healing after tooth extraction in the rachitic rats. Materials and Methods: In order to carry out this study, the rats were divided into four groups: Group 1 (normal diet/non-irradiation group), Group 2 (normal diet/irradiation group), Group 3 (rachitogenic diet/non-irradiation group), and Group 4 (rachitogenic diet/irradiation group). Rachitic changes were induced with rachitogenic diet No. 2 (high calcium, low phosphorus, and Vitamin D deficient diet) for 5 weeks. After the extraction of both maxillary first molars of the rats in Group 2 and 4, the head and neck of the rats were irradiated with single absorbed dose of 10 Gy. The rats were sacrificed at the 1st, 5th, 10th, and 15th day after tooth extraction. The specimens including the extraction wound were sectioned, stained with the hematoxylin-eosin and Masson's trichrome method and examined under the light microscope. Results: In the Group 2, the amount of newly formed bone trabeculae on the periphery of extraction socket and osteoblastic activity were reduced. In the Group 3, epithelial fusion was not revealed on the 5th day after toothe extraction and growth rate of osteoid formation was reduced. In the Group 4, necrotized tissue at the outer surface of extraction socket and destructive changes on the alveolar bones were noted on the 10th day. Epithelial fusion was not revealed and large amounts of osteoclast were noted on alveolar bone on the 15th day. Conclusion: The healing process of wound after tooth extraction was retarded by irradiation and especially in the rachitic rats.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.4
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• pp.301-307
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• 2001

There have been many trials to decrease the scar formation followed by wound treatment. $TGF-{\beta}$ plays a important role on wound healing in adult. Therefore the repression of $TGF-{\beta}$ expression will be helpful to decrease scar formation. Decorin is known to competitively inhibit $TGF-{\beta}$ expression. Decorin were subcutaneously administered in surgical wounds in rabbits to investigate the preventing effect of scar formation for clinical application. Histologic findings of wound healing progresses is similar with control and experimental group at 2week. $2.5{\mu}g$ decorin of administrated group was similar to those of control group at 4 and 8week. In wound healing process $10{\mu}g$ decorin of administrated groupsat showed that thickness of immature collagen fibers(scar) was decreased as compared with control group at 4, 8 weeks. $20{\mu}g$ decorin of administrated group showed similar histologic features to $10{\mu}g$ administrated group. The wounds of 8week experimental group(10, $20{\mu}g$) were completely recovered to the normal surrounding skin tissue including sweat gland and hair follicle. These results suggested that decorin can be of help to the prevention of local scar formation.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.351-358
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• 2011

Purpose: The inflammatory phase is considered an integral part of adult wound healing, but fetal wound healing studies have shown scarless healing results in the absence of the inflammation process. The COX-2 pathway is an essential component of inflammation. The purpose of this study is to identify the effect of a topical selective COX-2 inhibitor on inflammation in rabbit skin wound healing and scarring. Methods: Full-thickness wounds were made on 6 New Zealand rabbits' ears. Topical 5% celecoxib + vehicle (experimental tissue) and vehicle only (controlled tissue) were applied daily for 14d on each side of the ears. Scar samples were harvested at 2 wks, 4 wks, and 8 wks after the wounding. Each sample was stained with hematoxylin and eosin and the Masson's trichrome stain to evaluate inflammation and scar formation. Results: Histological analysis demonstrated a significant reduction of inflammation, neovascularization, and scar elevation in the experimental tissue as compared to the control. Additionally, experimental tissue exhibited faster improvement of collagen organization similar to that of normal tissue. Conclusion: This study suggests that the topical application of a selective COX-2 inhibitor on a rabbit ear wound resulted in decreased inflammation and had a positive effect on the reduction of scar formation.

• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.130-133
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• 2019

Ehlers-Danlos syndrome (EDS) is an inherited disorder of collagen biosynthesis and structure, characterized by skin hyperextensibility, joint hypermobility, aberrant scars, and tissue friability. Besides the skin, skeleton (joint) and vessels, other organs such as the eyes and the intestine can be affected in this syndrome. Accordingly, interdisciplinary cooperation is necessary for a successful treatment. Three basic surgical problems are arising due to an EDS: decreased the strength of the tissue causes making the wound dehiscence, increased bleeding tendency due to the blood vessel fragility, and delayed wound healing period. Surgery patients with an EDS require an experienced surgeon in treating EDS patients; the treatment process requires careful tissue handling and a long postoperative care. A surgeon should also recognize whether the patient shows a resistance to local anesthetics and a high risk of hematoma formation. This report describes a patient with a wide open wound on the foot dorsum and delayed wound healing after the primary approximation of the wound margins.

• Applied Microscopy
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• v.39 no.3
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• pp.253-260
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• 2009

GM-CSF is a multipotent growth factor, which also plays an important role during the process of wound healing. rrhGM-CSF was specifically produced from rice cell culture in our laboratory (Hanson Biotech Co., Ltd, Daejeon). The rrhGMCSF contains more oligosaccharide side chains than any other types of GM-CSF. This work was taken to evaluate the influence on wound healing of rrhGM-CSF in male golden hamsters. Full thickness skin defects of 9 mm in diameter were made in the back of hamsters, and 100 ${\mu}L$ ointment containing rrhGM-CSF 50 ${\mu}g/mL$ was applied. Control groups were given ointment without rrhGM-CSF. The wound sizes were relatively reduced and skin was well regenerated in the experimental group compared with the control group. Structurally, reepithelialization and architecture of the skin following injury were well accomplished in the experimental group. And also, positive reaction of PCNA of the skin following injury was more prominent in rrhGM-CSF containing ointment treatment group. Since this type of GM-CSF has highly glycosylated side chains, the effectiveness might be retain longer and stable, regarding acceleration of wound healing in the animal model. The present study has important implications for further development of the therapeutic manipulation of wound healing using rrhGM-CSF.

• Journal of Oral Medicine and Pain
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• v.19 no.1
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• pp.73-91
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• 1994

The author used rabbits in order to examine the effect of Ga-As low power generating semiconductor laser on artificially produced injuries of experimental animals. Artificially produced injuries include surgical wound of 3mm length, 2mm depth in size on ventral skin surface of rabbit and buccal mucosa, and electrical injury formed on opposite side of skin and buccal mucosa by electrical cauterization of same length and depth, and chemical injury formed by FC(Formocresol) solution applied on the anterior dorsal part of tongue. And then, on the experimental group, Ga-As laser was irradiated beginning on the day after the wound formation and continued to irradiate every each other day for five minutes. After1, 3, 6, 9, 13th day, certain number of animals of control and experimental group were sacrified, and wound site tissue was excised to make samples and was observed under light microscope. The following is the conclusions after comparing the healing procedure of experimental and control group. The following results were obtained : 1. Inflammation was decreased more rapidly in the experimental group than the control group. 2. In the surgical, the electrical and the chemical injuries in the oral mucosa, re-epithelialization was completed more rapidly in the experimental group than the control group. In the electrical injury on the skin, re-epithelialization was completed about 6 days after wound formation on both groups. 3. In the electrical and the surgical injuries on the oral mucosa, granulation tissue formation started at 3 days after injury on both groups, but in the chemical injury, it was completed about 3 days faster in the control group than the experimental group. In the surgical wound on the skin, it was completed about 9 days after injury, but faster in the experimental group. In the electrical injury on the skin, it was faster in the control group than the experimental group. 4. In the electrical and the surgical injuries on the oral mucosa, fibrosis was started at 6~9 days after injury on both groups, but regeneration of connective tissue in the experimental group was observed much more than the control group. 5. When comparing the effect of wound healing on skin and oral mucosa of control and experimental group, granulation tissue formation and re-epithelialization in the oral mucosa was more vigorous. In conclusion, the difference of timing and the sequence of wound healing process(inflammation, re-epithelialization, granulation tissue formation, fibrosis) following Laser irradiation between control and experimental group was not observed, but the healing tissue was observed much more in the Laser irradiated group.

• Journal of Periodontal and Implant Science
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• v.32 no.2
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• pp.291-302
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• 2002

In most of the previous studies, invasive and discrete techniques have been used to monitor the healing process of the gingival graft. However, Laser Doppler Flowmetry(LDF, floLAB(R), Moor Instruments Ltd., England) is a non-invasive technique for measurement of blood flow in the tissue and also allows continuous monitoring. Thus, we tested the usefulness of LDF in monitoring the healing process of free gingival graft at gingival recession. Eleven gingival graft site of 7 patients, including 5 males and 2 females, aged between 21 and 41 years (mean age 28.5) were monitored for the blood flow. The blood flow in gingival graft at coronal site, central site, apical site, mesial site and distal site was measured using LDF. Blood flow was measured at 1- week, 2- week, 3- week and 4- week after gingival graft surgery from 10 a.m. to 2 p.m. Time-course of the healing process was evaluated by statistical analysis using repeated ANOVA and Duncan test. The results were as follows : (1) Blood flow stayed increased for 2 weeks, and then, it was a tendency to decrease. (2) The blood flow at distal site had always higher than mesial site during the measuring periods. (3) The blood flow was high orderly after 1 week ; most coronal site, most apical site, central site. But that was high orderly after 2 week, 3 week, 4 week ; most coronal site, central site, most apical site. In conclusion, LDF was a useful and clinically adaptable method to monitor wound healing process. Our study suggested that it was important to protect surgical site to promote initial wound healing.

• The Journal of the Korean dental association
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• v.16 no.1 s.104
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• pp.43-50
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• 1978

The purpose of this study is to determine the effects of Cyclophosphamide on the healing process of fractures of the mice. Tweny-one young adult male mice were used. All of them were experimentally fractured in the left mandibular body areas, and Cyclophosphamide 0.1mg. per 30gr. body wt. was administrated intramuscularly to the experimental group. the mice of both control and experimental groups were sacrificed 1,3,5,7,10,14, and 21st day after operations and microscopic slides were made. The author has observed the histopathological findings. The results were as follows; 1. There were no specific difference between the experimental and control group in the early stage (1~5th day after operation) of the healing process of the mandibular fracture. 2. In the healing process of fractures 7-10th day after operation, the fibrous tissure formation and osteoblastic activity were poor in the experimental groop compared with the control group. 3. In the healing process of fractures 14-21th day after operation, the connective tissue and new bone formation were very poor in the experimental group compared with the control group. 4. On the whole, cyclophosphamide affected the experimentally fractured wound to delay healing in the jaw bone of the mice.