"Numerous reports on the immunopathogenesis of an oral lichen planus (OLP) have shown some inconsistency in terms of the role and distribution of CD4+ and CD8+ T cells, and Langerhans cells (LC). This has led to the hypothesis that although the clinical and histopathological manifestations of OLPs appear similar, they can be grouped into CD4+ predominant lesions and CD8+ ones on the varied immunopathogenesis or clinical progress. This study investigated the distribution of CD4+ T cells, CD8+ T cells, LC and the ratio of CD4/CD8 and defined the important immunocompetent cells. In addition, the clinicopathological and histopathological correlation with those immunocompetent cells were investigated. Frozen sections of 16 OLPs and 5 normal buccal mucosae were immunostained. Quantification was done using KAPPA Imagebase software and statistical analysis using SPSS 10.0 statistical package. CD8+ T cells were consistently more abundant in the epithelium of the OLP than CD4+ T cells, but no difference between the two cells was detected in the lamina propria. The intra-epithelial CD4+ T cells revealed a positive linear correlation with the intra-epithelial CD8+ T cells. In the lamina propria, the number of LC had a positive linear correlation with CD4/CD8 ratio. The number of LCs was higher in the reticular type of OLP compared to the erosive type. The histopathological features such as hyperkeratosis, acanthosis, the band-like infiltration of mononuclear cells, and liquefaction degeneration did not show significant correlation with the CD4/CD8 ratio. The results suggest that CD8+ T cells play major role in immunopathogenesis of OLP. The immunopathogenesis of OLP appears to vary from lesion to lesion in relation to the clinical progress. "

"Chronic hyperplastic candidiasis (CHC) is characterized by epithelial hyperplasia of the oral mucosa associated with candidal hyphae. The immune status of host is one of the factors that induce clinically evident candidal infection. Host defense mechanisms include inflammatory cells, epithelial barrier, and antimicrobial peptides such as human beta 2 defensin (hBD-2). In the present study, we investigated the densities of CD4+/CD8+ T lymphocytes and hBD-2 expression of epithelial cells in CHC. Immunohistochemical staining was performed on 10 cases of CHC using CD4, CD8 and hBD-2. Ten specimens of chronic mucositis were selected for comparison, and went through the same examination. hBD-2 was expressed in the spinous cell layers and the keratin layers of 7 CHC patients, while the epithelium of chronic mucositis did not demonstrate the hBD-2 expression except for one case. Also, hBD-2 expression was stronger when the hyphae invaded the upper stratum spinosum (P=.019). However, the densities of CD8+ T lymphocytes were significantly lower in the CHC patients, suggesting that the ability of CD8+ T cells to enter the epithelium and target the pathogenic hyphae was decreased in CHC. Increased hBD-2 expression seemed to be significantly associated with the candidal infection, while not promoting the cell-mediated immune reaction in CHC. "

"Odontogenic cysts are classified into inflammatory and developmental origins. The most common representative inflammatory cyst is periapical cyst and the most common representative developmental cyst is dentigerous cyst and cyst which show character of tumor is odontogenic keratocyst and cyst of which cystic epithleial lining cells transform to ameloblastoma is unicystic ameloblastoma. About ten years ago p63 protein that are closely related to p53 protein was found. Authors studied about comparative pattern of expression of p63 protein in periapical cyst, dentigerous cysts, odontogenic kertocysts and unicystic ameloblastomas. Authors selected 10 cases for every four types of cyst and performed immunohistochemical staining by using monoclonal antibody about p63 protein, LSAB(labelled streptoavidin biotin) reactant and HRP(horse raish peroxidase) system. Positive cells about p63 protein were expressed at basal layer of cystic lining epithelium in periapical cysts, odontogenic keratocysts and unicytic ameloblastomas. On the contrary, in dentigerous cysts positive cells were expressed at surfce layer. Perapical cysts and odontogenic keratocysts showed significantly high values of labelling indices.(periapical cyst:72.49%, odontogenic keratocyst:64.72%, dentigerous cyst:8.94%, unicystic ameloblastoma:5.25%) Odontogenic keratocyst showed the most strong staining intensity and the second was periapical cyst, the third was dentigerous cyst, and lastly unicystic ameloblastoma. Conclusively cause that the positive cells appeared at surface layer in dentigerous cyst reflected the position of epithelium to the enamel, and labelling indices of p63 protein were closely related to proliferative capacity and intensity of expression closely related to the labelling index and thus labelling index was also closely related to proliferative capacity of cystic lining epithelium."

"A 17-year-old male patient was referred for the extraction of impacted mesiodens and canine (#23) before orthodontic treatment. In the radiologic examination, an ovoid-shape radiolucent lesion was found with well-defined hyperostotic rim involved the teeth in left maxillary area. After biopsy examination the lesion was diagnosed as glandular odontogenic cyst (GOC) differentially from non-odontogrnic cysts, i.e., nasopalatine duct cyst. In the immunohistochemistry the cyst epithelium was freguently positive for PCNA, clearly positive for amtloblastin, slightly positive for β-catenin, but rarely positive for amelogenin and cytokeratin 7. Mucin and PRP were positive in the secretory cells of the cyst epithelium. On the other hand, TNFα was strongly positive in the macropahges infiltrated into the mucin-filled cyst lumen, and CD68 and CD31 were positive in the mucin-filled macropahges. These findings may indicate that the glandular elements are derived from hamartomatous secretory organ and that this odontogenic cyst is arisen from the embryonal rests of enamel epithelium, which has a potential to be differentiated into not only the enamel organ but also the secretory gland. Taken together, we assumed that the present case of GOC was originated from the odontogenic epithelium of impacted teeth, but showed the cytodifferentiation of glandular cells."

"Carcinoma ex pleomorphic adenoma is a rare malignant salivary gland tumor. The carcinomatous component of the carcinoma ex pleomorphic adenoma is mostly one type such as adenocarcinoma NOS, salivary duct carcinoma and undifferentiated carcinoma. We present a case of carcinoma ex pleomorphic adenoma including two carcinomatous components. The tumor occurred in the palate of a 70-year-old man. Histopathologically, the tumor was composed of both benign pleomorphic adenoma and the carcinoma area that showed adenocarcinoma NOS and squamous cell carcinoma. Finally this case was diagnosed as carcinoma ex pleomorphic adenoma including two carcinomatous components. "

"Tumor cells, especially in a malignant form, proliferate rapidly that blood supply within the tumors becomes limited, leading to a condition of insufficient oxygen supply. Such hypoxic condition is known to impair the viability of cancer cells, but it can also be a factor to facilitate the appearance of cells with a higher degree of malignancy. Indeed, the hypoxic condition created within malignant tumors may contribute to promoting their aggressive behaviors, including tumor invasion and metastasis, and to the development of resistance to various therapeutic modalities such as chemotherapy. Recently, microRNAs, a group of short RNA fragments consisting of 18 to 20 nucleotides, have been shown to participate in regulating genes important for cell survival, differentiation and apoptosis. Since their discovery, modulation of these microRNAs has been a focus of intensive studies with regard to their significance on gene regulation and various aspects of cell biology. In this study, we investigated hypoxia-induced alterations in microRNAs in oral squamous cell carcinoma (OSCC) cells and discussed consequential gene modulation and relevant cellular responses."

"Ameloblastomas are benign odontogenic tumor and the most common neoplasm in jaws and they have locally invasive property and high recurrence rate. Four typical subtypes ameloblastomas are plexiform, follicular, granular cell and acanthomatous type, but their developmental states during tumorigenesis are uncertain. And thus authors studied about developing states of four types of ameloblastomas by immunohistochemical staining for cytokeratin 8/18 which was an intermediate filament of epithelial cell origin and for vimentin which was an intermediate filament of mesenchymal cell origin, and then by comparative analyses of the results. Authors selected seven cases for every four types of ameloblastomas, and then performed immunohistochemcial staining for cytkeratin 8/18 and vimentin to all selected specimen by using monoclonal antibodies about cytoleratin 8/18 and vimentin, LSAB(Labelled StreptoAvidin Biotin) reactant and HRP(Horse Radish Peroxidase) system. Labelling indices of cytokeratin 8/18 of plexiform and follicular types of ameloblastomas were significantly high values in the group of ameloblast-like cells and labelling indices of cytokeratin 8/18 of all types of ameloblastoma were high values in the group of transformed cells, but their differences were not significant. Labelling index of vimentin of plexiform ameloblastoma was significantly high value in the group of ameloblast-like cells and others showed comparatively lower values. Labelling index of vimentin of granular cell type of ameloblastoma in the group of transformed cells was significantly high value and others showed comparatively lower values. Consequently the most primitive form of ameloblastoma was plexiform, and more differenciated form was follicular type and granular cell type and acanthomatous type were most differenciated form of ameloblastomas."

"Sialolithiasis consists of calcified structures in either the salivary gland or ductal system and alteration of salivary gland parenchyma. To investigate the clinicopathological features of sialolithiasis in Korean patients, we selected 60 patients with sialolithiasis diagnosed at the Seoul National University Dental Hospital. Their clinical records and radiographs were reviewed with the analysis of available histologic data from 32 cases. The male to female ratio was 1.1:1. Sialolithiasis is most common between the ages of 20 and 60 years and occurred most frequently in the submandibular gland (97%). Upon microscopic examination, most lesions showed moderate-to-severe inflammatory infiltration and parenchymal changes such as ductal metaplasia, acinar necrosis and fibrosis. Consequently, Korean patients exhibited clinicopathological features similar to those previously reported."

"Multinucleated giant cells appear in a variety forms in different types of oral lesion. However, their nature is still not well understood. Thus, to address this issue, the immunohistochemical characteristics of inflammatory giant cells (Langhans’ giant cells in lesions of tuberculosis and foreign body giant cells in odontogenic keratocysts and squamous cell carcinomas) and tumor giant cells in central giant cell granulomas were compared with those of osteoclasts, the normal giant cell, using a panel of macrophage and osteoclast marker antibodies, such as calcitonin receptor (CT-R), c-Src, Cathepsin K (Cath-K), CD14, RANK, and c-fms. The foreign body giant cells around cholesterol clefts in inflamed odontogenic keratocysts revealed more macrophage-like characteristics than the foreign body giant cells resorbing keratin pearls in squamous cell carcinomas. As such, both cases of foreign body giant cell exhibited immunoreactivity for the macrophage markers, such as CD14, RANK, and c-fms, yet only the latter case exhibited immunoreactivity for the osteoclast markers, such as CT-R and c-Src. Moreover, both cases of foreign body giant cells were positive for TRAP activity, yet negative for Cathepsin K activity. In contrast, the other inflammatory giant cells, Langhans’ giant cells, exhibited immunoreactivity for both the macrophage and osteoclast markers, yet were negative for TRAP activity. Meanwhile, the giant cells in the central giant cell granulomas reacted positively to both the macrophage and osteoclast markers, and were also positive for TRAP activity. Accordingly, these findings suggest that the immunoprofiles of giant cells in oral lesions vary according to the nature of the lesion, despite shared osteoclast and macrophage characteristics. Furthermore, the giant cells in tumorous lesions closely associated with bony destruction revealed more osteoclastic characteristics and their enzyme components were different according to the nature of the lesion."

"Oral squamous cell papillomas(OSCPs) showed various features in their etiology, histology, and prognosis. Therefore, it is necessary to diagnose differentially according to their pathological examinations. In the present study total 14 cases of OSCPs were evaluated and characterized to be three types of OSCPs, i.e., papillary papilloma, verrucous papilloma, and inverted papilloma. The present study demonstrated that among 14 cases of OSCPs papillary papilloma (n＝6) showed the typical papillary projection of squamous epithelium with severe acanthosis of upper spinous layer cells, accompanying frequent nuclear vacuolization. And verrucous papilloma (n＝7) showed the diffuse acanthosis of whole spinous layer cells with severe basal hyperplasia, resulted in the thick squamous epithelium exhibiting verrucous surface and irregularly ingrowing rete pegs. One case of inverted papilloma showed the typical ingrowth of basal layer cells deeply into underlying connective tissue, resulted in the formation of multiple fissures on the surface area. The present study also revealed the predominant nuclear vacuolization suspicious for viral infection in papillary papilloma, and also heavy smoking history in the verrucous papilloma. On the other hand, as the epithelium of inverted papilloma ingrew into the underlying deep connective tissue up to the muscular layer, it is supposed that the inverted papilloma has a potential of basal layer proliferation strong enough to invade the protecting barrier of underlying connective tissue, or that the underlying connective tissue was too weak to prevent the ingrowth of basal layer epithelium. Taken together, because the OSCPs show heterogenous origins and variable pathological prognosis, it is suggested that the OSCPs should be differentially diagnosed at least into three types, i.e., papillary papilloma, verrucous papilloma, and inverted papilloma."

"1. 대한구강병리학회 창립일에 대한 소고 2. 대한구강안면병리학회 역대 임원명단3. 대한구강안면병리학회 회칙 및 규정 4. 대한구강안면병리학회 역대 학술대회 5. 대한구강안면병리학회 역대 정기총회, 예산 결산 안 6. 대한구강안면병리학회 역대 회무, 이사회"

"Socket sclerosis can be an obstacle for orthodontic space closure, however, the precise histomorphogenetic mechanism has not been elucidated up to date. A 73 years old female complained of dull pain on palpation in the extraction site of the left maxillary first molar, and uncomfortable to use her complete denture. In panoramic X-ray view the socket sclerosis was clearly demarcated as a radiopaque outline of extracted root. In histological examination the socket sclerosis showed the basophilic deposition of cementum-like materials in the peripheral rim of trabecular bones instead of eosinophilic osteoid materials for intramembranous ossification. In the immunohistochemical staining for osteogenetic proteins, BMP-2 was strongly positive in the peripheral rim of trabecular bone, in which RANKL and osteoprotegerin were also consistently positive. Particularly, versican, a marker of cementum was also positive in the peripheral rim of the trabecular bone. Therefore, it is presumed that the trabecular bones of socket sclerosis were hypermineralized by cementoid ossification, producing cementum-like materials by osteoblasts/cementoblasts derived from the previous periodontium."