• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제31권3호
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• pp.219-227
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• 2005

Purpose: Abnormalities in the p53 gene are regarded as the most consistent genetic abnormalities detected in head and neck squamous cell carcinogenesis. Two new members of the p53 gene family, p73 and p63 have recently been identified. They share considerable sequence homology with p53 in the transactivation, DNA binding, and oligomerization domains, indicating possible involvement in carcinogenesis. Disruption of the homeostatic balance between proliferation and apoptosis is widely believed to contribute to human oral carcinogenesis. The aim of this study was to analyze expression of p63 in squamous cell carcinogenesis and to compare with immunochemical markers representing cell proliferation and apoptosis. Materials and Methods: Using the Syrian hamster oral cancer model, the fraction of apoptotic (apoptotic index-AI), proliferating (mitotic index-MI) and p63 expressing keratinocytes were examined at normal, dysplastic and malignant oral epithelium using the TUNEL assay, PCNA and p63 immunostaining. Results: p63 significantly increased between normal and dysplastic epithelium and between dysplastic and malignant epithelium. PCNA significantly increased between normal and dysplastic epithelium and between normal and malignant epithelium. However, increase between dysplastic and malignant epithelium, though still increasing, was not statistically significant. The percentage of TUNEL positive cells increased from normal to dysplastic epithelium and returned to normal keratinocyte level in the malignant epithelium. However, differences between tissue types were not significant. The ratio of MI:AI increased significantly only in the dysplastic-malignant epithelial transition. The increase of p63 expression closely reflected the change in the MI:AI ratio during oral carcinogenesis. Conclusion: The p63 may be associated with the regulation of epithelial proliferation and apoptosis in DMBA-induced hamster buccal pouch squamous cell carcinogenesis. Further study is required to investigate which p63 isoforms are involved in hamster buccal pouch carcinogenesis.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권2호
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• pp.124-136
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• 2001

Heat shock protein (HSP) expression is unregulated in tumor cells and, HSP expression is likely marker of the malignant potential of oral epithelial lesion. Furthermore, the 70kDa HSP is implicated in the degree of tumor differentiation, the rate of tumor proliferation and the magnitude of the anti-tumor Immune response. Accordingly, the distribution and intensity of HSP70 and HSP47 expression was assessed in the DMBA induced oral carcinogenesis in hamster. Golden Syrian hamsters which were 3 months-age and $90{\sim}120g$ were collected. 9,10-dimethyl -1,2-benzanthracene (DMBA) in a 0.5% solution in mineral oil was painted on the buccal pouch mucosa 3 times per week in the study group. In each control and experimental groups of 6, 8, 10, 12, 14, 16, 18, 20 weeks, specimen were sectioned for immunohistochemical study with anti-HSP47 and anti-HSP70 antibody. The following results were obtained. 1. HSP47 positive cells were race or negative of normal oral mucosa, increased mildly in basal and suprabasal basal layer, and spinous cell layer after experimental 6 weeks (dysplastic or CIS stage). In CIS stage, HSP47 expression is prominent in dysplastic free or normal adjacent epithelium. 2. HSP47 positive cells in connective tissue were mainly inflammatory cells, which is gradually increased from control to precancerous and cancer stage. But HSP47 positive cells after 14 weeks were decreased, especially normal and cancer adjacent epithelium. 3. The positive staining cells of HSP70 in control, dysplastic, and CIS stage were not seen. But they were mild findings in basal layer and moderate findings in spinous layer after experimental 14 weeks (cancer stage). 4. HSP70 positive cells were increased in precancerous and cancer stage than control group in connective tissue. After experimental 16 weeks, we could not find the HSP expression in cancer cells according to cancer differentiation or cancer stage. It is concluded that HSP70 or HSP47 expression is not a definitive marker of oral malignancy or malignant potential. However, with further development, HSP immunoreactivity may be valuable as an adjunct to conventional histology for assessing the malignant potential of oral mucosal lesions.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제20권4호
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• pp.362-372
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• 1998

Heat shock protein (HSP) expression is unregulated in tumor cells and, HSP expression is likely marker of the malignant potential of oral epithelial lesion. Furthermore, the 70kDa HSP is implicated in the degree of tumor differentiation, the rate of tumor proliferation and the magnitude of the anti-tumor immune response. Accordingly, the distribution and intensity of HSP 70 and HSP 47 expression was assessed in the DMBA induced oral carcinogenesis in hamster. Golden Syrian hamsters which were 3 months-age and 90-120g were collected. 9,10-dimethyl-1,2-benzanthracene (DMBA) in a 0.5% solution in mineral oil was painted on the buccal pouch mucosa 3 times per week in the study group. In each control and experimental groups of 6, 8, 10, 12, 14, 16, 18, 20 weeks, specimen were sectioned for immunohistochemical study with anti-HSP47 and anti-HSP70 antibody. The following results were obtained. 1. HSP47 positive cells were rare or negative of normal oral mucosa, increased mildly in basal and suprabasal basal layer, and spinous cell layer after experimental 6 weeks (dysplastic or CIS stage). In CIS stage, HSP47 expression is prominent in dysplastic free or normal adjacent epithelium. 2. HSP 47 positive cells in connective tissue were mainly inflammatory cells, which is gradually increased from control to precancerous and cancer stage. But HSP47 positive cells after 14 weeks were decreased, especially normal and cancer adjacent epithelium. 3. The positive staining cells of HSP70 in control, dysplastic, and CIS stage were not seen. But they were mild findings in basal layer and moderate findings in spinous layer after experimental 14 weeks (cancer stage). 4. HSP70 positive cells were increased in precancerous and cancer stage than control group in connective tissue. After experimental 16 weeks, we could not find the HSP expression in cancer cells according to cancer differentiation or cancer stage. It is concluded that HSP70 or HSP47 expression is not a definitive marker of oral malignancy or malignant potential. However, with further development, HSP immunoreactivity may be valuable as an adjunct to conventional histology for assessing the malignant potential of oral mucosal lesions.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제27권6호
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• pp.510-522
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• 2005

To assess the clinical applicability of bio-artificial mucosa which was made with autologous oral keratinocytes and human acellular dermal matrix, the formation of basement membrane and stratification of oral keratinocytes were evaluated. Six New Zealand white rabbits (around 2kg in weight) were anesthetized and its buccal mucosa was harvested (1.0 $\times$ 0.5cm size). Oral keratinicytes were extracted and cultured primarily with the feeder layer of pretreated NIH J2 3T3 fibroblast. These confluent cells were innoculated on the human acellular dermal matrix and cultured in multiple layer by air-rafting method. After 3, 5, 7, 10, 14 days of culture, each cultured bio-artificial mucosa was investigated the number of epthelial layer of by H&E stain and toluidine blue stain. The immuhohistochemical methods were used to evaluate the cell division capacity, the formation of basement membrane, and it's property of specific cells (PCNA, cytokeratin 14, laminin). Transmission electromicroscopy was used for the attachment between cells and matrix with the number of hemidesmosome. In result, the numbers of layer of stratified growth of oral keratinocyte cultured on the human acellular dermal matrix and the number of hemidesomal attachment between epithelial cells and human acellular dermal matrix were similar to the layers of normal oral mucosa after 10 days of culture. The cell division rate, basement membrane formation and proliferation rate increased as culture period increased. With these results, bio-artificial mucosa with autologous oral epithelial cells cultured on the acellular dermal matrix had clinically adaptable properties after 10 days' culture and this new bio-artificial mucosa model with relatively short culture time can be expected clinical applicability.

• Journal of Periodontal and Implant Science
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• 제49권4호
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• pp.215-227
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• 2019

Purpose: To histologically characterize periodontal healing at 8 weeks in surgically created dehiscence defects in beagle dogs that received a collagen matrix with periodontal ligament (PDL) progenitor cells. Methods: The bilateral maxillary premolars and first molars in 6 animals were used. Standardized experimental dehiscence defects were made on the buccal side of 3 premolars, and primary culturing of PDL progenitor cells was performed on the molars. Collagen matrix was used as a scaffold and a delivery system for PDL progenitor cells. The experimental sites were grafted with collagen matrix (COL), PDL progenitor cells with collagen matrix (COL/CELL), or left without any material (CTL). Histologic and histomorphometric analyses were performed after 8 weeks. Results: The defect height from the cementoenamel junction to the most apical point of cementum removal did not significantly differ across the CTL, COL, and COL/CELL groups, at $4.57{\pm}0.28$, $4.56{\pm}0.41$, and $4.64{\pm}0.27mm$ (mean ${\pm}$ standard deviation), respectively; the corresponding values for epithelial adhesion were $1.41{\pm}0.51$, $0.85{\pm}0.29$, and $0.30{\pm}0.41mm$ (P<0.05), the heights of new bone regeneration were $1.32{\pm}0.44$, $1.65{\pm}0.52$, and $1.93{\pm}0.61mm$ (P<0.05), and the cementum regeneration values were $1.15{\pm}0.42$, $1.81{\pm}0.46$, and $2.57{\pm}0.56mm$ (P<0.05). There was significantly more new bone formation in the COL/CELL group than in the CTL group, and new cementum length was also significantly higher in the COL/CELL group. However, there were no significant differences in the width of new cementum among the groups. Conclusions: PDL progenitor cells carried by a synthetic collagen matrix may enhance periodontal regeneration, including cementum and new bone formation.

• Journal of Oral Medicine and Pain
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• 제19권1호
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• pp.33-43
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• 1994

The purpose of this paper was to observe the influence of Ga-As semiconductor-low power generating laser on she appearance and actions of tenascin, extracellular matrix, as healing process of intentional wound on the experimental animals is taking place. 35 rabbits were divided into control and experimental group. ; and on each, 3mm-long and 2mm-deep, surgical wounds were created on buccal oral mucosa and thoracodorsal portion of skin. Ga-As laser was applied to the experimental group starting a day of the day the wounds were created , the laser was applied for 5 minutes every other day. Tissue samples were taken after the 2, 4, 7, 10, and 14 days after wound formation. Then tile healing process of experimental and control groups were observed and compared, using light microscope. Afterwards, the samples were immunohistochemical stained and again observed tenascin by quantitative measuring. The following results were obtained : 1. Tenascin was observed prevalently on epithelial cells, border area of dermis, and interstitial matrix between connective tissue layers in both experimental and control groups. 2. In oral mucosa, the experimental group showed significant increase in the appearance of tenascin after 4 days compared to the control group, but after 10 days, it decreased to a point which is even less than the control group. 3. In the skin samples, the pattern of appearance of tenascin was the same in both groups, but there was some difference concerning when the peak period was shown, In the experimental group, the peak period of tenascin expression was the 7 days after wound formation in epithelium and connective tissue. In the control group, the peak period was 10 days after. 4. In both the experimental and control groups, tenascin first appeared in the epithelium near the wound area and submucosa, and then spread on the underlying connective tissue. In conclusion, appearance of tenascin is closely related to regeneration of epithelium and development of granulation tissue : therefore, low power laser, which fastnes appearance of tenascin, is sure to faciltate healing process of oral mucosa.

• Journal of Periodontal and Implant Science
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• 제36권1호
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• pp.27-37
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• 2006

Although the main purpose of periodontal treatment to regenerate is the complete regeneration of periodontal tissue due to periodontal disease, most of the treatment cannot meet such purpose because healing by long epithelial junction. Therefore, diverse materials of resorbable and non-resorbable have been used to regenerate the periodontal tissue. Due to high risk of exposure and necessity of secondary surgical procedure when using non-resorbable membrane, guided tissue regeneration using the resorbable membrane has gain popularity, recently. However, present resorbable membrane has the disadvantage of not having sufficient time to regenerate date to the difference of resorption rate according to surgical site. Meanwhile, other than the structure stability and facile manipulation, acellular dermal matrix has been reported to be a possible scaffold for cellular proliferation due to rapid revascularization and favorable physical properties for cellular attachment and proliferation. The purpose of this study is to estimate the influence of acellular dermal matrix on periodontal ligament, cementum and alveolar bone when acellular dermal matrix is implanted to 1-wall alveolar bone defect. 4 dogs of 12 to 16 month old irrelevant to sex , which below 15Kg of body weight, has been used in this study. ADM has been used for the material of guided tissue regeneration. The 3rd premolar of the lower jaw was extracted bilaterally and awaited for self-healing. subsequently buccal and lingual flap was elevated to form one wall intrabony defect with the depth and width of 4mm on the distal surface of 2nd premolar and the mesial surface of 4th premolar. After the removal of periodontal ligament by root planing. notch was formed on the basal position. Following the root surface treatment, while the control group had the flap sutured without any treatment on surgically induced intrabony defect. Following the root surface treatment, the flap of intrabony defect was sutured with the ADM inserted while the control group sutured without any insertion. The histologic specimen was observed after 4 and 8 weeks of treatment. The control group was partially regenerated by periodontal ligament, new cementum and new alveolar bone. the level of regeneration is not reached on the previous formed notch. but, experimental group was fully regenerated by functionally oriented periodontal ligament fiber. new cementum and new alveolar bone. In conclusion, we think that ADM seems to be used by scaffold for periodontal ligament cells and the matrix is expected to use on guided tissue regeneration.