• Restorative Dentistry and Endodontics
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• 제25권2호
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• pp.289-298
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• 2000

Carbamide peroxide is usually used for vital teeth bleaching at home. Complications such as tooth hypersensitivity and/or gingival irritation are frequently reported. Therefore, this study was performed to evaluate any possible histological changes in pulp and periodontal tissue by carbamide peroxide bleaching gel in rats. 10% and 15% carbamide peroxide containing nightguard for upper molar were worn for 4 hours a day. The rats were sacrificed after 1 day, 2 days, 3 days, 4 days and 6 days application of carbamide peroxide respectively. The results were as follows : Mild infiltration of inflammatory changes below the junctional epithelium and hyperplasia of epithelium were observed in both 10% and 15% carbamide peroxide treated groups. In all experimental groups, odontoblasts were changed from columnar to cuboidal shape and/or obliterated and the focal loss of predentin was observed in pulp horn. With increasing time of application, these changes were more remarkable, but limited in pulp horn. Inflammatory reactions, vacuolar changes and hyaline degenerations of the pup tissue were also observed in some cases. These results suggested that carbamide peroxide gel used in home bleaching could cause reversible pulpal irritation.

• 대한치과의사협회지
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• 제25권11호통권222호
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• pp.1043-1054
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• 1987

• 대한치과의사협회지
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• 제16권3호통권106호
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• pp.193-195
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• 1978

The author observed the effect of x-ray irradiation on the tooth germ development of the rat fetuses. The lower right abdomen of the pregnant rats were exposed to x-ray irradiation (400 rads) on 9½th day of qestation. At 18½th day of qestation, the fetuses were removed from their mothers and histological sections of molar region were prepared. The results were as folows: 1. In the experimental fetuses, no significant changes appeared in the histological aspects of the enamel pulp, except the poor development of the innerenamel epithelium in the cusp region. 2. Pulp cells of cusp region in the irradiated fetuses were not differentiated to odontoblasts, The arrangement and population of pulp cells showed marked regional differences in the dental papilla. 3. Developmental features of dental follicle of irradiated fetuses were similar with controls.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6609-6613
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• 2015

Background: Matrix metalloproteinases (MMPs) are a family of zinc metalloproteinases capable of degrading components of connective tissues. MMP-10 is frequently expressed in human cancers. The aim of this study was to immunohistochemically evaluate its expression in oral squamous cell carcinoma (OSCC) and verrucous carcinoma (OVC). Materials and Methods: A retrospective analysis of 73 samples (31 OSCC, 22 OVC and 20 non-neoplastic epithelium) was performed. All samples were immunohistochemically stained with monoclonal MMP-10 antibody and expression levels and staining intensity were evaluated with respect to microscopic features. Data were analyzed by SPSS (V.21), Mann-Whitney and Kruskal Wallis tests. Results: MMP-10 was detected in all OSCC and OVC cases. The expression of MMP-10 in OSCC was intensive (score 3) and in OVC was low and moderate (score 1 and score 2) more frequently. Non- neoplastic epithelium did not show MMP-10 expression. Differences between groups was statistically significant (p<0.05). However, the expression of MMP-10 was not obviously different between various grades of OSCC. Conclusions: According to our study, MMP-10 protein can be important possible factor in the transformation of normal oral epithelium to OVC and OSCC, also the level of MMP-10 expression at invasion front of the lesions can be helpful in the differentiation of OVC and OSCC.

• Journal of Periodontal and Implant Science
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• 제54권1호
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• pp.25-36
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• 2024

Purpose: Mucogingival defects (MGDs), such as dental root recessions, decreased vestibular depth, and absence of keratinized tissues, are commonly seen in dental clinics. MGDs may result in functional, aesthetic, and hygienic concerns. In these situations, autogenous soft tissue grafts are considered the gold-standard treatment. This study compares the healing process of free gingival grafts (FGGs) to bacterial cellulose matrix (BCM) and human acellular dermal matrix (ADM) seeded with fibroblasts from culture supplemented with platelet-rich plasma in a rat model. Methods: Surgical defects were made in rats, which received the following treatments in a randomized manner: group I, negative control (defect creation only); group II, positive control (FGG); group III, BCM; group IV, BCM + fibroblasts; group V, ADM; and group VI, ADM + fibroblasts. Clinical, histological, and immunological analyses were performed 15 days after grafting. Clinical examinations recorded epithelium regularity and the presence of ulcers, erythema, and/or edema. Results: The histological analysis revealed the degree of reepithelization, width, regularity, and presence of keratin. The Fisher exact statistical test was applied to the results (P<0.05). No groups showed ulcers except for group I. All groups had regular epithelium without erythema and without edema. Histologically, all groups exhibited regular epithelium with keratinization, and myofibroblasts were present in the connective tissue. The groups that received engineered grafts showed similar clinical and histological results to the FGG group. Conclusions: Within the limitations of this study, it was concluded that BCM and ADM can be used as cell scaffolds, with ADM yielding the best results. This study supports the use of this technical protocol in humans.

• 치과방사선
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• 제24권2호
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• pp.327-333
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• 1994

The purpose of this study was to investigate the irradiation effects on the palatal mucosa. For this study, Sprague-Dawley strain rats were irradiated to their head and neck region with the dose of 5Gy and l0Gy by 6MV X -radiation and sacrificed on the experimental periods after irradiation. The authors observed the histological changes of the hard and soft palatal mucosae. The results were as follows: In the light microscopic examination, hydropic change on the basal cells, increased cell size of the epithelium, and decreased epithelial cell layers were observed on the 3hours, 6hours, and 12hours groups after irradiation. But, basal cell hyperplasia, increased epithelial cell layers, and elongated rate pegs were observed on the 3days group after irradiation. After then, these changes were recovered in the mucosa of the hard palate on the 7days and 14days groups, and in the mucosa of the soft palate on the 14days and 2&lays groups after irradiation. And such changes were greater in the mucosa of the soft palate than in that of the hard palate, and more prominent in l0Gy irradiated groups than in 5Gy irradiated groups.

• Imaging Science in Dentistry
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• 제34권4호
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• pp.209-213
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• 2004

The glandular odontogenic cyst is a rare lesion described in 1987. It generally occurs at anterior region of mandible in adults over the age of 40 and has a slight tendency to recur. Histopathologically, a cystic cavity lined by a nonkeratinized, stratified squamous, or cuboidal epithelium varying in thickness is found including a superficial layer with glandular or pseudoglandular structures. A 21-year-old male visited Dankook University Dental Hospital with a chief complaint of swelling of the left posterior mandible. Radiographically, a huge multilocular radiolucent lesion involving impacted 3rd molar at the posterior mandible was observed. Buccolingual cortical expansion with partial perforation of buccal cortical bone was also shown. Histopathologically, this lesion was lined by stratified squamous epithelium with glandular structures in areas of plaque-like thickening. The final diagnosis was made as a glandular odontogenic cyst.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제25권4호
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• pp.311-323
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• 1999

The osteonectin is a sort of glycoprotein which is secreted in human tissues. The osteonectin is generally detected in number of normal or neoplastic human tissues in vivo, but hasn't been studied the role of osteonectin in developing human teeth and odontogenic tumors. We evaluated degree of the expression of osteonectin immunohistochemically in 20 cases of developing tooth germ which growth from fetus 5 to 38 weeks, and total 51 odontogenic tumors whitch has taken from routine biopsy, such as 10 ameloblastomas, 5 cases of adenomatoid odontogenic tumors and odontomas and odontogenic fibromas, 4 cases of cementomas and calcifying epithelial odontogenic cyst and odontogenic keratocyst and dentigerous cysts and periapical cysts, and 3 cases of ameloblastic fibromas and myxomas. The results were as follows: 1. The osteonectin on the bud stage of tooth germ was strongly expressed in the epithelial dental lamina and in the outer dental epithelium on the early bell stage, and also strongly expressed in the inner dental epithelium on the late bell stage of tooth germs. 2. In ameloblastoma, the osteonectin was strongly expressed in the epithelial tumor component and especially in the acanthomatous types. 3. In both of calcifying epithelial odontogenic tumor and adenomatoid odontogenic tumors, the osteonectin was moderately expressed on the duct like spindle cells and epithelial tumor cells around calcification areas. 4. In odontogenic tumors originated from epithelial-mesenchymal tissues, the osteonectin was moderately expressed on the epithelial tumor components and in odontogenic cysts, it was expressed in ghost cells and calcification areas only. These were summaried the osteonectin may be strongly related to the developing tooth germ and odontogenic tumors and could be regulated hard tissue of human tooth in morphogenesis and involved with calcification mechanism in development odontogenic tumors.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권6호
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• pp.553-555
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• 2010

Ameloblastoma is a common odontogenic tumor originating from the dental lamina, reduced dental epithelium and rests of Malassez, and represents 10% of all odontogenic tumors of the jaw. Unicystic ameloblastoma is normally encountered in young patients, and often occurs in the mandible, and is particularly associated with an impacted tooth. We encountered an unicystic ameloblastoma arising from a dentigerous cyst after the treatment of a radiolucent lesion on the mandible.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권1호
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• pp.60-64
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• 2004

Squamous papilloma is a benign proliferation of stratified squamous epithelium, resulting in a papillary or verruciform mass. Verrucous carcinoma is a differentiated variant of squamous cell carcinoma and may present diagnostic difficulties as it may be erroneously diagnosed as squamous papilloma. Squamous papilloma is similar to other oral mucosa malignancy in microscopic view. So, it is difficult to distinguish between squamous cell papilloma and other oral mucosa malignancy. Here are three patients. they were diagnosed as squamous papilloma initially, but the lesion was recurred. In recurred lesion, verrucous carcinoma or squamous cell carcinoma were found. So we report that recurred oral mucosa malignency(verrucous carcinoma or squamous cell carcinoma) which was diagnosed as squamous papilloma.