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The Analysis and Study of First Visit Outpatients in Oral Medicine (구강내과에 내원한 신환에 관한 분석 연구)

  • Ko, Myung-Yun;Heo, Jun-Young;Ok, Su-Min;Kim, Kyung-Hee;Jeong, Sung-Hee;Ahn, Yong-Woo
    • Journal of Oral Medicine and Pain
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    • v.38 no.2
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    • pp.137-142
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    • 2013
  • Oral Medicine includes temporomandibular disorder, orofacial pains such as neuropathic pain, soft tissue diseases, halitosis, laser treatment, snoring, sleep apnea and identification through forensic dentistry etc. Such diseases are relatively common and cause great inconvenience and pain to the patients, as well as incur fatal health scare at times. In terms of oral medicine, the number of orofacial patients is growing due to a change in the life style and an increased stress as time goes in contemporary society and the demand of areas requiring oral medical professionalism, such as soft tissue lesions, snoring and sleep apnea, forensic dentistry evaluation and others are rapidly ascending. Consequently, among the areas in dental science, the calls for the expertism in oral medicine and its role are mounting. Analyzing the distribution according to disease entity, symptoms, duration of disease, and the prehistory courses of new patients visiting the department of oral medicine in a year provides information of the role and the relative importance of oral medicine in prospect and enables effective diagnosis and treatments for the patients. Therefore, in the present study, by analyzing new patients visiting the oral medicine clinic in our dental hospital for a year and by evaluating the role and the professionalism in future oral medicine, the authors concluded the followings: 1. It was founded that new patients to oral medicine mainly had temporomandibular disorders, soft tissue diseases, and neuropathic pains. 2. The number of patients with temporomandibular disorder appeared to be the highest percentage and the order within this was the patients with combined disorders, muscle disorder, and internal derangement of joint disc. 3. The number of patients with xerostomia appeared to be the highest percentage within soft tissue disease, followed by lichen planus and recurrent apthous ulcers. 4. The number of patients with burning mouth syndrome appeared to be the highest percentage within neuropathic pain.

Comparison of relative fitness between zirconia single coping and 3-unit fixed partial dentures (FPDs) manufactured by dental CAD/CAM system (치과 캐드/캠 시스템으로 제작된 지르코니아 single 코핑과 3-unit 구조물의 상대적 적합도 비교)

  • Lee, Wan-Sun;Park, Jong-Kyoung;Kim, Wook-Tae
    • Journal of Dental Rehabilitation and Applied Science
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    • v.30 no.1
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    • pp.16-22
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    • 2014
  • Purpose: The purpose of this study was to assess the marginal and mesial fitness of zirconia single copings and 3-unit fixed partial dentures (FPDs) manufactured with an identical model. Materials and Methods: An epoxy model in which the maxillary right 2nd premolar is lost and maxillary 1st premolar and 2nd molar are formed as abutments was manufactured and scanned by using a laser scanner. A ten units of zirconia single copings were manufactured for maxillary 1st premolar and 2nd molar, respectively and the same number of 3-unit FPDs were manufactured. For the measurements of fitness, the manufactured silicone replicas were divided into four parts and the fitness were measured by digital microscope at measurement points (P1, P2, P3, P4 and P5) of each plane. The measured gaps were classified into three categories: marginal gap (MG, P1), axial gap (AG, average of P2 and P3), occlusal gap (OG, average of P4 and P5). Results: The ranges of MG, AG and OG for single copings were 18.47 - 40.54 ${\mu}m$, 39.73 - 73.61 ${\mu}m$ and 116.90 - 134.69 ${\mu}m$, respectively. The ranges of MG, AG and OG for 3-unit FPDs were 45.95 - 87.44 ${\mu}m$, 23.78 - 57.00 ${\mu}m$ and 99.89 - 131.06 ${\mu}m$, respectively. Conclusion: The result of the study shows that the MGs for 3-unit FPDs were higher than those of single copings, though they are within the range of clinical acceptance, indicating that the use of more homogeneous zirconia block and modification of sintering processes are needed to ensure the prevention of increase of gap in 3-unit FPDs.

A Study on the Measurement of the Dimensionless Light Extinction Constant for Particulate Matter from Fuel Oil for Marine and Land Diesel Engines (선박 및 육상 디젤 엔진용 연료유에서 발생하는 입자상물질에 대한 무차원 광소멸계수 계측에 관한 연구)

  • Rho, Beom-Seok;Choi, Jae-Hyuk;Cho, Kwon-Hae;Park, Seul-Hyun;Lee, Won-Ju
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.2
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    • pp.275-281
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    • 2018
  • It is known that he pollutant emitted from the combustion process of marine fuel oil causes air pollution and harmful effects to the human body. Accordingly, IMO regulates pollutants emitted from ships. However, the regulation of Particulate Matter (PM) is still in the process of debate, so preemptive action is needed. Fundamental research on PM is essential. In this study, the Dimensionless Light Extinction Constant ($K_e$) of fuel oil used in marine diesel engines was measured and analyzed to construct the basic data of the PM generated from marine-based fuel oil. The fuel oil used in the land diesel engine was measured in the same way for character comparison. Both fuel oils differ in sulfur content and density. The $K_e$ was measured via the optical method using a 633 nm laser and was determined by using the volume fraction of PM collected by the gravimetric filter method. The $K_e$ of the PM discharged from marine fuel oil is 8.28, and the land fuel oil is 8.44. The $K_e$ of two fuel oils was similar within the measurement uncertainty range. However, it was found by comparison with the value obtained by the Rayleigh-Limit solution that the light scattering portion could be large. Also, it was found that light extinction characteristics could be different due to the relationship between light transmittance and collected mass.

Components and Biological Activity of Aqueous Extract Isolated from Winged Stem of Euonymus alatus (화살나무 물 추출물의 구성성분과 생리활성)

  • Oh, Bong-Yun;Hwang, Soo-Kyung;Cheong, Mi-Young;Sin, Hong-Sig;Park, Bock-Hee;Lee, Jeong-Ho;Kim, Soo-Hyun
    • Korean Journal of Food Science and Technology
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    • v.37 no.6
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    • pp.898-904
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    • 2005
  • Although Euonymus alatus (EA) has been used as traditional medicine for cancer treatment, exact substances involved in curing of the disease are not yet known. Free radical scavenging and reactive oxygen species (ROS) removal activities of aqueous extract components isolated from winged stem of EA in animal cell line were investigated. Aqueous extract of EA (AEEA) was fractionated by ultrafiltration. All fractions mainly consisted of polysaccharide (44.8%), protein (2.1%), small amounts of phenol compounds and organic acids. Antioxidant activity of AEEA increased depending on concentration fractions, as determined by 1,1-diphenyl-2-picrylhydrazyl method. ROS removal activity was visualized in Chinese hamster ovary cell line using laser scanning confocal microscope, and AEEA activity increased in order of F IV>F III>F I>F II. These results suggest AETA has bioactive carbohydrates with potentials as functional foods and antioxidants.

Military Competition and Arms Control in Space (우주상 군비경쟁과 군비통제)

  • Shin, Dong-Chun;Cho, Hong-Je
    • The Korean Journal of Air & Space Law and Policy
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    • v.26 no.2
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    • pp.203-237
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    • 2011
  • Since USSR successfully launched its satellite "Sputnik"in 1957, many countries including US and USSR began military use of space, and engaged in arms race in space, which is against spirit and ideals of peaceful use of space as common heritage of mankind stipulated in many treaties such as Outer Space Treaty. With worsening Cold War between East and Western Bloc, this military use of space and arms race in space has been intensifying. Regarding the ideals of peaceful use of space, it is interpreted that military use of space is possible unless it does not have the purpose of aggression. The military use of space may have diverse forms such as attacking satellites in space, or attacking from satellites, making use of present and future technologies available which should include the use of nuclear and kinetic/hyper-speed weapons, laser, particle beams, near explosion, disturbance weapons in different directions (i.e., surface to space, space to space, and space to surface). Arms control is being implemented by the efforts of many countries in different formalities including legislature of international treaties under the auspices of UNCOPUOS and prohibition of weapons of mass destruction. Taking outstanding examples aiming at arms control by international community, there are confidence building measures (CBM), strengthening implementation of existing treaties, partial ban of nuclear tests, countryand regional approach, comprehensive approach and measures having legally binding force. While U.S. has surpassed other countries concerned in the area of military useof space, it withdrew from OST in early 2000s, thereby raising concern of international community. It requires concerted efforts of cooperationand implementation by international society to make sure peace of mankind and environmental conservation through arms control in space. Observing de facto possession of nuclear weapons by North Korea following series of nuclear tests and launching satellites, and efforts of launching rockets by South Korea, it is strongly needed for both countries to take part in arms control efforts by international community.

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Superoxide Dismutase Gene Expression in the Endotoxin-Treated Rat Lung (내독소에 의한 백서 폐장의 Superoxide Dismutase 유전자 발현에 관한 연구)

  • Yoo, Chul-Gyu;Suh, Gee-Young;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.3
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    • pp.215-221
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    • 1994
  • Background: It is well known that oxygen free radicals(OFR) play a vital role in the various type of acute lung injury. Among various antioxidant defense mechanisms, the superoxide dismutases(SOD) are thought to be the first line of antioxidant defense by catalyzing the dismutation of two superoxide radicals to yield hydrogen peroxide and oxygen. Eukaryotic cells contain two types of intracellular SOD : cytosolic, dimeric copper/zinc- containing enzyme(CuZnSOD) and mitochondrial, tetrameric manganese-containing enzyme(MnSOD). The purpose of this study is to evaluate the time-dependent gene expression of MnSOD and CuZnSOD in the endotoxin-treated rats, and to compare with the manifestations of LPS-induced acute lung injury in rats. Methods: Total RNA from rat lung was isolated using single step phenol extraction 0, 1, 2, 4, 6, 12, 18, 24 hours after E. coli endotoxin injection(n=3, respectively). RNA was separated by formaldehyde-containing 1.2% agarose gels elctrophoresis, transblotted, baked, prehybridized, and hybridized with $^{32}P$-labeled cDNA probes for rat MnSOD and CuZnSOD, which were kindly donated by Dr. Ho(Duke University, Durham, NC, USA). The probes were labeled by nick translation. Blots were washed and autoradiography were quantitated using laser densitometry. Equivalent amounts of total RNA/gel were assessed by monitoring 28S and 18S rRNA. Results: Endotoxin caused a rise in steady-state MnSOD mRNA levels by 4h with peak mRNA accumulation by 6h. Continued MnSOD mRNA expression was observed at 12h. CuZnSOD mRNA expression was observed from 1h to 24h with peak levels by 18h. Conclusion: These results suggest that SOD palys an important defensive role in the endotoxin-induced acute lung injury in rats.

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Detection of rpoB Gene Mutation in Rifampin-Resistant M. Tuberculosis by Oligonucleotide Chip (Oligonucleotide chip을 이용한 Rifampin 내성 결핵균의 rpoB 유전자 돌연변이 검출)

  • Park, Soon-Kew;Lee, Min-Ki;Chung, Byung-Seon;Kim, Cheol-Min;Chang, Chul-Hun L.;Park, Hee-Kyung;Jang, Hyun-Jung;Park, Seung-Kyu;Song, Sun-Dae
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.5
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    • pp.546-557
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    • 2000
  • Background : Oligonucleotide chip technology has proven to be a very useful tool in the rapid diagnosis of infectious disease. Rifampin resistance is considered as a useful marker of multidrug-resistance in tuberculosis. Mutations in the rpoB gene coding $\beta$ subunit of RNA polymerase represent the main mechanism of rifampin resistance. The purpose of this study was to develop a diagnosis kit using oligonucleotide chip for the rapid and accurate detection of rifampin-resistance in Mycobacterium tuberculosis. Method : The sequence specific probes for mutations in the rpoB gene were designed and spotted onto the glass slide, oligonucleotide chip. 38 clinical isolates of Mycobacterium were tested. A part of rpoB was amplified, labelled, and hybridized on the oligonucleotide chip with probes. Results were analyzed with a laser scanner. Direct sequencing was done to verify the results. Result : The low-density oligonucleotide chip design어 to determine the specific mutations in the rpoB gene of M. tuberculosis accurately detected rifampin resistance associated with mutations in 28 clinical isolates. Mutations at codons 531, 526, and 513 were confirmed by direct sequencing analysis. Conclusion : Mutant detection using oligonucleotide chip technology is a reliable and useful diagnostic tool for the detection of multidrug-resistance in M. tuberculosis.

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AN EXPERIMENTAL STUDY ON THE MICROTENSILE BONDING STRENGTH OF DENTIN TREATED BY $CARISOLV^{TM}$ ($Carisolv^{TM}$ 에 의한 우식제거후 Microtensile Bonding Strength에 관한 연구)

  • Baik, Byeong-Ju;Kwon, Byoung-Woo;Kim, Jae-Gon;Cheon, Cheol-Wan
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.3
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    • pp.389-396
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    • 2002
  • The purpose of this study was to compare the microtensile bonding strength of chemomechanically excavated dentin($Carisolv^{TM}$) to conventional caries removal(bur). The following adhesive systems were used; AB: All-Bond 2(3M, USA), PB: Prime & Bond 2.1(Dentsply, DE), AQ: AQ Bond(sun medical, Japan). 42 human molars with occlusal caries were assigned to 6 groups. Sequential caries removal was controlled with laser fluorescence. Each group was devided as follows; group A, B, C were $Carisolv^{TM}$ applied, group D,E,F were bur used. In group A and D, AB was used as a dentin adhesive. group B,E and group C,F was AQ and AQ was used each. The cavity was filled with composite resin(Z-100). The specimens were sectioned vertically into multiple serial 0.7 mm thick slabs. And then those slabs were sectioned into rectangular parts under 0.7 mm width. Finally 0.7-1.0 mm a right hexahedron shape stick become. Microtensile bonding test was carried out with testing apparatus at cross-head speed of $0.5\;mm/min^{-1}$ and fractured surfaces were observed with scanning electron microscope(JSM-6400, Jeol, Japan). The obtained results were summarized as follows ; 1. In the group of caries removal with $Carisolv^{TM}$, micro-tensile bonding strength decreased to $75.8{\sim}80$ percent of bur used group. 2. In the group of caries removal with $Carisolv^{TM}$, decreased degree of micro-tensile bonding strength is not so different in 3 kinds of dentin adhesives(p<0.05). 3. In the group of caries removal with $Carisolv^{TM}$, microtensile bonding strength of AB, PB, AQ was 32.6MPa(2.4), 30.1Mpa (1.8), 21.2Mpa(1.9). 4. In the group of caries removal with Bur and $Carisolv^{TM}$, microtensile bonding strength of AQ was significantly lower than that of AB and PB(p<0.01).

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IN VITRO COMPARISON OF VARIOUS DIAGNOSTIC METHODS OF OCCLUSAL CAR10US LESIONS (교합면 우식병소의 다양한 진단법에 관한 비교연구)

  • Kim, Jae-Gon;Kim, Young-Jin;Kim, Young-Sin;Baik, Byeong-Ju
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.4
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    • pp.613-619
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    • 2001
  • The aims of this study were to compare the accuracy, sensitivity and specificity of cnventional visual examination, radiography and a new laser fluorescence method, KaVo Diagnodent, for the detection of occlusal caries lesions. One hundred sound human premolars and molars which had no restorations or interproximal cavities were tested by three methods. Tooth lesions depth was assessed at histologic examination using Caries detector dye The following results were obtained. 1. Diagnodent show 7.8 in sound tooth, 25.4 in initial caries, 30.5 in enamel caries, and 53.8 in dentin caries with average score 2. Spearman and Pearson relation coefficient was high between tooth-specimen test with dye and Diagnodent(0.736, 0.619), visual examination(0.664, 0.666), and was low between tooth-specimen test with dye and radiographic examination(P<0.01, total) 3. Accuracy of occlusal caries was highest on Diagnodent(65%) and lowest on radiographic examination(35%) 4. In initial caries, the sensitivity and specificity of Diagnodent method was the highest. In enamel caries, the sensitivity of visual examination was the highest and specificity of Diagnodent method was the highest. In dentinal caries, the sensitivity and specificity of Diagnodent method was the highest and sensitivity of visual examination was the lowest.

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Elemental analysis of the fluoride varnish effects on root caries initiation (불소 바니쉬 도포 후 초기 치근 우식 발현에 대한 정량원소분석)

  • Park, Se-Eun;Yi, Kee-Wook;Kim, Hae-Young;Son, Ho-Hyun;Chang, Ju-Hea
    • Restorative Dentistry and Endodontics
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    • v.36 no.4
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    • pp.290-299
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    • 2011
  • Objectives: The usage of fluoride varnish for a moderate to low caries-risk group has not been well validated. This study aimed to evaluate the preventive and therapeutic efficacies of fluoride varnish on the initiated root caries. Materials and Methods: Ten premolars were sectioned into quarters, further divided into two windows, one of which was painted with Fluor Protector (1,000 ppm fluoride, Ivoclar Vivadent). An initial lesion with a well-preserved surface layer was produced by pH cycling. Scanned line analysis using energy dispersive spectrometry determined the weight percentages of Ca and P in the demineralized layer. Scanning Electron microscopy and confocal laser scanning microscopy (CLSM) evaluated the varnish-applied root surfaces. Results: The mean lesion depth (SD) was 12.3 (2.6) ${\mu}m$ (single cycling) and 19.6 (3.8) ${\mu}m$ (double cycling). Double cycling extended the lesion depth, but induced no more mineral loss than single cycling (p < 0.05). The mean weight percentages of Ca and P between groups with and without varnish were not significantly different (p < 0.05). A CLSM showed varnish remained within 15 ${\mu}m$ of the surface layer. Conclusions: When a mild acid challenge initiated root tissue demineralization, the application of low-concentration fluoride varnish did not influence the lesion depth or the mineral composition of the subsurface lesion.