"The aim of this study was to analyze factors indicating preventive removal of mandibular third molars by determining associated symptoms, pathologies, eruption state, position and angulation types of mandibular third molars.A retrospective study was made of 436 patients(200 females, 236 males), aged between 12 and 81 years (mean: 29.93 years) undergoing panoramic radiographic examinations. Total 700 mandibular third molars were analyzed. They were divided by age, sex, position and angulation of mandibular third molars, bony coverage, and associated pathologies- caries, pericoronitis, periodontitis, cyst, root resorption of adjacent teeth. Among 409 pathologies associated with mandibular third molars, pericoronitis accounted for 34.2%(140 cases), which was the most common lesion, caries in the second and third molars for 28.9%, caries in the second molars for 11%(45 cases). Periodontitis showed in 7%(29 cases). In 4 cases, root resorption of adjecent tooth showed. The position which showed predominant pathologic lesion according to the Pell and Gregory classification was ‡UA(86.5%), followed by ‡UB(71.6%). Mandibular third molars without bony coverage(64.8%) showed pathologies frequently.The removal of mandibular third molars must be determined by the perceived risk if the teeth are not removed. The position and inclination of the third molars, bony coverage, age and sex of patients can be the important evidence in the decision making process."

"Hippo signaling is one of the signal transduction pathways revealed in Drosophila and mammalian. This signaling is known to control proliferation and growth of normal cells or cancer cells, in which many signaling proteins form a network. In this network, tumor suppressor kinases include MST and LATS while YAP and TAZ exist as oncoproteins. Combined with transcription factor, YAP the oncoprotien starts to secrete growth factors such as CTGF, FGF, and Cry61 regulating the growth of cells or the organ sizes. The YAP is also associated with the development of early embryo and the regeneration of the skin wound as well as abnormal growth of cancers in case of over-expression. Although many previous studies have found various tumors with YAP over-expressed, the expression of YAP is not yet clearly identified in oral cancer.The aim of this study was to check the expression level of YAP in oral squamous cell carcinoma. So we performed PCR and Western blot to check YAP expression in mRNA and protein level respectively. In result, all of the 13 cell lines examined has presented the expression of YAP, and especially in HSC2 and KOSCC11 cell lines has been observed the remarkable level of expression.In conclusion, we confirmed the overexpression of YAP cell line in oral squamous cell carcinoma, it will be a great help to the study carried out in the future. Once you understand the mechanism of oncoprotien YAP in oral cancer cells, it seems possible to research and development of targeted tumor therapy agents in oral cancer."

Immunoprecipitation-based high performance liquid chromatography (IP-HPLC) is a type of modified enzyme-linked immunosorbent assay (ELISA) that uses protein A/G (or antibody)-conjugated beads instead of the antibody-conjugated wells used in ELISA. In order to determine the fidelity of IP-HPLC, the author used 83 antisera to identify protein expression changes caused by cisplatin treatment in KB human oral cancer cells. KB cells were cultured for 12 or 24 hours with 10 ug/mL cisplatin. The results obtained by IP-HPLC were comparable with published cisplatin data, although ELISA was not conducted in the present study. Cisplatin dominantly reduced the levels of proteins associated with cell proliferation, transcription factors, growth factors, cytoskeletal proteins, and cellular differentiating factors, but on the other hand, apoptosis-related factors, oncogenes, and protective proteins were usually up-regulated, presumably to address cisplatin-induced DNA damage. In particular, cisplatin directly inactivated genomic DNA by down-regulating histone H1 and demethylase and by up-regulating deacetylase. Cisplatin also rapidly induced p53 overexpression and mitochondria-mediated endogenous apoptosis occurred after 12 hours of cisplatin treatment, although this was almost completely replaced by FASL/FAS-mediated exogenous apoptosis after 24 hours. This preliminary study was conducted to investigate the anticancer effect of cisplatin on the KB human oral cancer cells and to determine the fidelity of IP-HPLC data. It was concluded that IP-HPLC is useful for identifying profile changes of genome wide essential proteins and signaling changes of major molecular pathways.

Caliber persistent artery (CPA) is a vascular anomaly presenting as a bluish and pulsatile artery in the subepithelial tissue. Although the incidence of CPA was debated, many CPAs occurred in the perioral and facial tissues at which the embryonal strapedial artery networks were distributed. The present study demonstrated a case of CPA occurred in the retromolar buccal mucosa in a 37 years old male. The lesion showed many pinkish granular spots, but was asymptomatic except biting irritation during mastication. It had slowly increased in size up to 20 × 25 mm for 3 years, and recently became hemorrhagic due to the biting injury between left upper and lower second molars. With the fear of oral cancer an incisional biopsy was performed, and followed by histological and immunohistochemical study. Histologically the lesion showed many tortuous artery localized at the submucosa area, and the arterial wall was thick and its lumen was narrowed and shrunken. In the immunochemistry α-SMA was positive for thick smooth muscle layer of artery and arterioles, TGase 2 was weakly positive for the luminal surface of arterial intima, and bFGF was consistently positive for the perivascular fibrous tissue. But PCNA, VEGF, CD31, CMG2, TGF-β1, HSP-70, and 14-3-3 were almost negative for the vascular tissue. Therefore, it was presumed that the lesion was not actively proliferative nor degenerative but still retained its cellular stability and slow growing potential. It was finally diagnosed as CPA differentially from arterio-venous malformation, hemangioma, lymphangioma, and squamous cell carcinoma. The retromolar buccal mucosa CPA is first reported in this study and may present usual clinical findings depending on its size and location. This asymptomatic lesion could be severely hemorrhagic by minor biting injury, therefore, precise differential diagnosis should be made through biopsy, and careful therapy be followed.

Osteonecrosis is defined as non-vital bone tissue as a result of abnormal process of osseous healing, and is caused by several reasons such as infection, radiation, and medication. Osteomyelitis, osteoradionecrosis, and medication related osteonecrosis of the jaws (MRONJ) which have necrotic bone in common are confused clinically due to similar symptoms and radiographic findings, and are difficult to diagnose definitively. Because each disease represents a separate clinical progress and requires a different treatment approach, it is very important to distinguish each disease. The aim of this study was to analyze the histopathologic features of osteomyelitis, osteoradionecrosis, MRONJ and to understand their different pathogenesis.

"Malignant gliomas and glioblastomas are the most common type of primary brain tumors. The treatment of malignant glioma involves surgery, radiation, and chemotherapy. These therapies have not been successful in curing malignant glioma and typically associated with dismal prognosis. Therefore, we can investigate thymidine kinase activity and cytotoxic effect after transfer suicide gene in U-251 glioma cells. We assessed expression patterns of green fluorescence protein(GFP) after infected with adenovirus in U-251 cells. After infection of HSV-tk in U-251 cells, we observed thymidine kinase activity with [3H]-penciclovir and cytotoxic effect by treated with ganciclovir.We could observe that expression level of GFP was increased according to infected concentrations in U-251 cells. GFP was not expressed in 1moi and 10moi, and slightly expressed in 30moi. Expression level of GFP was largely increased in 50moi and almost cells expressed GFP in 100moi. GFP expression has shown clear image in 100moi compared with other concentrations. We also investigated thymidine kinase activity using [3H]-penciclovir after infection of suicide gene HSV-tk into U-251 cells. Thymidine kinase activity increased in 10moi concentration compared with empty adenovirus infection. We could find that thymidine kinase activity was elevated proportional to HSV tk infection amount in 30moi and 50moi. For evaluation of cellular cytotoxic effect of HSV-tk, we treated ganciclovir to U-251 cells and assessed cytotoxicity by using MTT assay. We could identifiy that cytotoicity appeared in very low concentration of HSV-tk compared with cancer cells originated with other organs. Cytotoxic effect was shown about 15% of U-251 cells of total cells in 5moi. By infection 10moi of HSV-tk, cytotoxic effect was intensively increased and about 60% of U-251 cells became extinct. About 70% cells exhibited cytotoxic effect in 30moi and more than 80% cells also appeared cytotoxic effect by infection of HSV-tk in 50moi, 100moi, and 200moi. Therefore, we could confirm to gene expression in U-251 cells was increased proportional to infected gene concentrations. Also we could find that thymidine kinase activity elevated with according to infected concentration and cellular cytotoxic effect was shown in very low concentration and higher cytotoxic effect also appeared by infection of suicide gene HSV-tk into U-251 glioma cells. These results suggest that gene therapy with suicide gene will be successful in curing brain tumors containing malignant glioma and glioblastoma."

" The purpose of this study was to synthetically examine the relationship between systemic diseases and periodontal diseases. The data of the Fifth Korea National Health and Nutrition Examination Survey were used. SPSS 18.0 for Windows was applied for statistical analysis. The surveyed data were analyzed by using independent sample t-test for the difference between Body Mass Index and clinical test according to the existence of periodontal disease, and X2test for the relationship between periodontal disease and systemic disease. Multiple logistic regression analysis was used in order to figure out the influence upon the existence of periodontal disease prevalence among general characteristics and relevant factors to systemic disease. As results, the value of high density lipoprotein (HDL) and HBA1C were statistically significant, depending on the presence of periodontal disease. As for the relationship between periodontal disease and systemic disease, hypertension (odds ratio 1.362, p<.05), cardiovascular disease (odds ratio 2.118, p<.05), arthritis (odds ratio 1.289, p<.05) and cirrhosis (odds ratio 6.124, p<.05) were statistically significant.In conclusion, the majority of the systemic diseases such as cardiovascular system, diabetes, and liver diseases have been considered to have relationship with periodontal disease. To strengthen oral health education is needed to enhance systemic health as well as oral health. Moreover, basic biological research should be followed to support this surveyed study."

Odontogenic cyst and odontogenic tumor shares developmental source. However, they have different histopathologic features, and they are classified respectively. Odontogenic cyst and tumor can share same physical region. It is called a hybrid lesion, a lesion showing the combined histopathological characteristics of two or more previously recognized odontogenic tumor and/or cysts of different categories. In this study, a hybrid lesion was researched. 61-year old man was referred to our department with a multilocular radiolucency in right mandibular angle. Incisional biopsy was carried out, and the patient was diagnosed with ameloblastoma. Odontogenic keratocyst was found with the tumor, and it was thought to be evolved via neoplastic transformation from lining epithelium of the keratocyst. After reviewing studies reporting hybrid lesions from odontogenic cyst and tumor, formation of a hybrid lesion was most frequent from a dentigerous cyst and an adenomatoid odontogenic tumor. A hybrid lesion commonly lead to misdiagnosis, and the prognosis is not always transparent. The close relationship between the odontogenic cyst and tumor has to be kept in mind in the diagnosis and treatment of the lesions in maxillofacial area.

Calcifying cystic odontogenic tumor (CCOT), also known as calcifying odontogenic cyst or Gorin cyst is a rare developmental lesion which arises from odontogenic epithelium. It has been classified as a benign odontogenic neoplasm related to odontogenic apparatus by the World Health Organization. CCOT may be associated with other odontogenic tumors, most frequently odontoma, a finding that is a rare event in other types of odontogenic cysts or tumors. This report describes a case of hybrid odontogenic tumor composed of CCOT and ameloblastic fibroma-odontoma of the impacted right maxillary canine region that occurred in a 14-year-old female.

We present a case of intraparotid plexiform neurofibroma in a 7-year-old man. The lesion was determined as plexiform neuroma in histopathological findings, but final diagnosis was plexiform neurofibroma considering his familiy history of neurofibromatosis and café au lait spots on his body. Currently we are executing follow-up after removing the tumor with surgery. Plexiform neurofibroma can develope at any point along a nerve and spread out either just under the skin or deeper in the body. According to the literature, the most common site of plexiform neurofibroma is mouth and face in the head and neck region. Also, plexiform neurofibroma occurs at 8.8-year-old in neurofibromatosis typeⅠ patient with familial history. Because of interlacing with adjacent normal tissue and the invasive nature we have difficult resecting the mass completely. So when the tumor turns symptomatic or disfiguring leading to an aesthetic problem, surgery had better be undertaken.

We present a case of intraparotid plexiform neurofibroma in a 7-year-old man. The lesion was determined as plexiform neuroma in histopathological findings, but final diagnosis was plexiform neurofibroma considering his familiy history of neurofibromatosis and café au lait spots on his body. Currently we are executing follow-up after removing the tumor with surgery. Plexiform neurofibroma can develope at any point along a nerve and spread out either just under the skin or deeper in the body. According to the literature, the most common site of plexiform neurofibroma is mouth and face in the head and neck region. Also, plexiform neurofibroma occurs at 8.8-year-old in neurofibromatosis typeⅠ patient with familial history. Because of interlacing with adjacent normal tissue and the invasive nature we have difficult resecting the mass completely. So when the tumor turns symptomatic or disfiguring leading to an aesthetic problem, surgery had better be undertaken.

Epidermoid cyst of the oral and maxillofacial region is a soft tissue cyst lined with keratinized stratified squamous epithelium and most commonly arises in the superficial area of the mouth floor. Uncommonly, the epidermoid cyst may arise deeply in the submandibular region and should be differentially diagnosed with cystic salivary gland tumors, developmental cysts and other cystic lesions. We report a rare case of an epidermoid cyst near the submandibular gland, clinically and radiographically mistaken as a salivary gland tumor.