• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.530-534
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• 2011

This paper reports two cases of schwannomas arising from the oral cavity. One is an intraoral ancient schwannoma located at the left cheek, which evolved over a period of 13 years. The tumor was a well-demarcated buccal mass, which was located in the left lower first premolar area, with an obliterated the buccal vestibule, leaving the overlying mucosa intact. The second case was a central intraosseous schwannoma located from the left lower 1st molar periapical area to the left 3rd molar periapical area. Pathologically, the first mass was composed of the spindle shaped tumor cells with wavy nuclei beneath the fibroconnective tissue of the gingiva but second case mass was not. Occasional nuclear pleomorphism was observed but mitosis or necrosis was absent. There were Antoni A and B areas along with strong, diffuse staining with the S-100 protein. Ancient schwannomas were diagnosed. Schwannoma is a slow-growing benign tumor, and an ancient schwannoma that shows cellular atypism is a variant of a schwannoma caused by purely degenerative changes. To date, only limited cases of ancient schwannomas in the oral cavity have been reported.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.22 no.1
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• pp.161-168
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• 1992

The authors observed a 27-year-old male patient who came to the Infirmary of Kyungpook National University Hospital who had complained of dull pain in right mandibular angle area 1 month ago. As a result of careful analysis of clinical, radiological, and histopathological findings, the authors diagnosed it as Ewing's sarcoma and obtained the results as follows: 1. In clinical examination, main clinical symptoms were continuous dull pain and gingival swelling on the 2nd and 3rd molar area of the right mandible. 2. In radiographic examination, ill-defined radiolucent area was seen on mandibular right angle area, and apparent periosteal reaction of sun-ray spicule was emanated from the lingual cortex of mandibular angle area. And computed tomograph also revealed moderate-defined 3. soft tissue mass of the same area. In histopathological examination, small round-shaped, and closely packed cells with scanty cytoplasm were observed in this specimen, and positive reaction in PAS staining was also observed.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.1
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• pp.17-25
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• 1995

The purpose of this study was to obtain some informations for the radiographic differential diagnosis between odontogenic keratocyst and unicystic ameloblastoma in the mandible. The author compared and analysed the clinico-radiographic features of 48 cases of odontogenic keratocyst and 32 cases of unicystic ameloblastoma. The obtained results were as follows : 1. Odontogenic keratocyst and unicystic ameloblastoma occurred the most frequently in the 2nd and 3rd decades, and both lesions occurred with slight predilection in males. The most frequent lesional site was molar area in odontogenic keratocyst(50.0％) and mandibular angle and ramus area in unicystic amelobla-stoma(71.9％). 2. Cortical thinning and expansion were observed with similar occurrences in odontogenic keratocyst(77.l％) and in unicystic ameloblastoma(72.9％). 3. Typical undulating lesional border was observed more frequently in odontogenic keratocyst(79.2％) than in unicystic ameloblastoma(46.9％). 4. Well-defined lesional outline occurred more frequently in odontogenic keratocyst(97.9％) than in unicystic ameloblastoma(53.1％). 5. Root resorption of adjacent teeth occurred more frequently in unicystic ameloblastoma(65.2％) than in odontogenic keratocyst(18.8％) respectively, but loss of lamina dura was frequently observed in odontogenic keratocyst(79.2％). And tooth displacement occurred more frequently in odontogenic keratocyst(50.0％) than in unicystic ameloblastoma(17.4％). 6. Displacement of mandibular canal occurred more frequently in odontogenic keratocyst(75.0％) than in unicystic ameloblastoma(61.5％). 7. Inhomogeneous lesional radiolucency occurred more frequently in unicystic ameloblastoma(53.l％) than in odontogenic keratocyst(39.6％).

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.1
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• pp.55-63
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• 1999

The author observed and compared the radiographic features of 49 cases of the fibrous dysplasia and 14 cases of the ossifying fibroma in the osteoblastic or mature stage radiologically and histopathologically. The obtained results were as follows: 1. Fibrous dysplasia occurred most frequently in the 2nd decade, but ossifying fibroma in the 3rd and 4th decades, and both lesions occurred with slight predilection in females. 2. In most cases, chief complaints were painless facial swelling. And 61.1％ of fibrous dysplasia occurred in the maxilla, 92.9％ of ossifying fibroma in the mandible, and most of these lesions occurred in the premolar-molar region. 3. In the mandibular lesions, ossifying fibroma was shown more oval and round shape. but fibrous dysplasia was shown fusiform shape. 4. Fibrous dysplasia was shown homogeneously distributed. complete radiopaque shadow at 63％, and ossifying fibroma was shown concentric. mixed appearance of radiolucent and radiopaque shadow at 92.9％. 5. Fibrous dysplasia was entirely shown poorly outlined and blended to normal surrounding bone, but ossifying fibroma was shown well-defined border. 6. Cortical thinning and expansion were observed in these lesions. but degree of cortical expansion was more severe in ossifying fibroma than fibrous dysplasia. 7. Loss of lamina dura. tooth displacement. and displacement of mandibular canal were observed in both lesions. but root resorption was observed in ossifying fibroma only.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1661-1667
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• 2016

The ginsenoside-hydrolyzing β-glucosidase gene (bgy2) was cloned from Lactobacillus brevis. We expressed this gene in Escherichia coli BL21(DE3), isolated the resulting protein, and then utilized the enzyme for the biotransformation of ginsenosides. The bgy2 gene contains 2,223 bp, and encodes a protein of 741 amino acids that is a member of glycosyl hydrolase family 3. β-Glucosidase (Bgy2) cleaved the outer glucose moieties of ginsenosides at the C-20 position, and the inner glucose at the C-3 position. Under optimal conditions (pH 7.0, 30℃), we used 0.1 mg/ml Bgy2 in 20 mM sodium phosphate buffer (PBS) for enzymatic studies. In these conditions, 1.0 mg/ml ginsenoside Rb1 and ginsenoside F2 were converted into 0.59 mg/ml ginsenoside Rd and 0.72mg/ml compound K, with molar conversion productivities of 69% and 91%, respectively. In pharmaceutical and commercial industries, this recombinant Bgy2 would be suitable for producting ginsenoside Rd and compound K.

• Imaging Science in Dentistry
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• v.35 no.1
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• pp.47-50
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• 2005

Purpose : To acquire the useful diagnostic information through the analysis of the clinical and radiological characteristics of mandibular unicystic ameloblastoma. Materials and Methods : The researchers compared and analysed the clinical and radiological features of 79 cases of mandibular unicystic ameloblastoma confirmed by histopathlogic examination. Results : The results of our research showed that unicystic ameloblastomas occurred more frequently in males than in females and the incidence is the highest in the 2nd and 3rd decades. These lesions occurred most frequently in angle-ramus area, mandibular molar area, and anterior area in descending order respectively $68.4\%$, $24\%$, and $7.6\%$. These lesions had smooth ($54.4\%$) rather than undulating ($45.6\%$) borders. These lesions showed well- defined borders in $59.5\%$ among all the cases. Root resorption and loss of lamina dura were observed as $55.7\%$ and $58.5\%$ respectively. Displacement of mandibular canal was observed in $55.9\%$ among all the related cases. Internal pattern of lesional radiolucency was observed as even ($49.4\%$) or uneven ($50.6\%$). Conclusion : These results would be helpful in diagnosing of mandibular unicystic ameloblastoma. (Korean J Oral Maxillofac Radiol 2005; 35 : 47-50)

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.2
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• pp.174-178
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• 2006

Brain abscess is a rare, extremely aggressive, life-threatening infection. It may occur following : infection of contiguous structure, hematogenous spread, or cranial trauma/surgery. Dental pathology and/or treatment have been linked to a small number of brain abscesses as possible source of infection. 50-year-old male patient was presented with a brain abscess caused by Streptococcus viridans. In the case presented, the significant oral findings were chronic periapical and periodontal infection due to root remnant of lower right 3rd molar. A case history and brief literature review of brain abscess related odontogenic infection was presented after successful treatment with antibiotics and craniotomy.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.248-256
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• 2020

This study aimed to evaluate the effects of national dental screening for children in Korea in the aspects of prevention of dental caries, the number of treatments related to dental caries, and cost of dental care. The study used the national cohort data on children health screening provided by National Health Insurance Service, and analyzed 32,937 1st dental screening, 22,608 2nd dental screening, 13,708 3rd dental screening, and 241,043 cases from the dental care of 27,944 children born in year 2008 and 2009. The decayed-filled teeth index and decayed-filled person rate, calculated from the results of the 2nd and 3rd dental screening, decreased as the number of preceding dental screening increased. Glass ionomer and amalgam restoration, pulp treatment of primary teeth and extraction of primary canine and molar were shown to decrease as the number of examined dental screening increased, and the total cost of dental care covered by national health insurance also decreased as the number of dental screening increased. In conclusion, national dental screening for children is an efficient and economical oral health care method that prevents dental caries and lowers the possibility of dental caries related treatment, thereby reducing cost of dental care.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.433-442
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• 1998

The purpose of this study was to observe the changes of acidity of resin cement(Time Line), glass ionomer cement(GC Fugi Lining LC), zinc phosphate cement(Fleck's zinc cement). zinc oxide eugenol cement(Sultan,Chemists.) in vivo and in vitro. Class I cavities with 3mm depth were prepared on the occlusal surfaces of 20 recently extracted human Mn. molar teeth and 20 human Mn. 3rd molar teeth in oral cavity. The prepared cavities were divided into 4 groups of each 5 teeth using the above 4 cavity liners. Each cement was mixed in accordance with manufacturer's direction at the room temperature of $23^{\circ}{\pm}5^{\circ}C$ and filled into the cavity in a width of 1 mm. The microelectrode of pH meter was inserted into the prepared cavity which was filled with mixed cement, and the acidity of cement was measured for 3 days from the beginning of cement mix in vitro and in vivo. The measured acidity was then statistically analyzed by ANOVA. The results were as follows. 1. In vitro, the pH of zinc oxide eugenol cement was statistically lower than that of the three other groups at 2min, 4min, 6min, 8min, 10min, 12min, 18min, 20min. (p<0.05). 2. The pH of zinc oxide eugenol cement in vivo was statistically higher than that in vitro at 16min,16min, 20min(p<0.05). 3. The pH of zinc phosphate cement in vivo was statistically higher than that in vitro at 4min, 20min(p<0.05). 4. In vitro and in vivo, there was no significant difference in the pH between the resin cement and the glass ionomer cement(p>0.05). 5. The initial acidity was not high, but almost neutral in all kinds of the cements.

• Restorative Dentistry and Endodontics
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• v.23 no.2
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• pp.597-606
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• 1998

The purpose of this study was to evaluate the shear bond strength of the Compoglass Carvifil bonded on the dentin surface according to etching or non-etching and two time application or three time application of single component. Human non-carious 60 extracted 3rd molar were used. The occlusal dentin surfaces of all teeth were exposed with Diamond Wheel Saw and polished with Lapping & Polishing machine(South Bay Technology Co., U.S.A). The teeth were then distributed randomly into four groups of 15 teeth each and dentin surface were conditioned as following. Control group : Non-etching, two times application of Syntac Single Component. (According to manufacture's instruction) Experimental group 1 : Non-etching, three times application of Syntac Single Component. Experimental group : 2 Etching, two times application of Syntac Single Component. Experimental group 3 : Etching, three times application of Syntac Single Component. Compoglass were bonded to exposed dentin surfaces and all samples were placed in distilled water for 7 days. The shear bond strengths were measured by universal testing machine (SHIMADAZU AUTOGRAPH, AGS-4D., Japan). The results were as follows : 1. Experimental group 3 revealed the highest value (30.75${\pm}$4.74 MPa) and control group revealed the lowest value(14.85${\pm}$2.69 MPa). There was significant difference of shear bond strength among four groups(P<0.01) 2. The acid-etching groups (experimental group 2, 3) had higher shear bond strengths than non etching groups(control group and experimental group 1). 3. The additional application of Syntac single component groups revealed a higher bond strength than two times application groups (control group and experimental group 2).