• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.1
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• pp.45-59
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• 2011

According as gradually increasing the demand for Eco-friendly products it has been progressed fairly development at a field of printing and printing inks. The Inks are used by soy oil beginning of ink industry for preventing environment. Now it is possible to make Eco-friendly inks with vegetable ester. So it is not necessary to use petroleum-based solvents for preventing environment. But There is some problems if using vegetable ester to inks. Vegetable ester has high solubility, it causes misting and low viscosity of the Inks. So resin is required high performance. Thus, in this paper, I studied about the properties variation of the Varnish and inks According to using the phenolic modified rosin ester and Soy oil Methyl esters. The compared in order of average molecular weight by the GPC method, rheological properties were found by rotational rheometer, and emulsion behavior were compared by high speed emulsification tester.

• Toxicological Research
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• v.27 no.4
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• pp.191-203
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• 2011

There has been growing concern about the toxicity of phthalate esters. Phthalate esters are being used widely for the production of perfume, nail varnish, hairsprays and other personal/cosmetic uses. Recently, exposure to phthalates has been assessed by analyzing urine for their metabolites. The parent phthalate is rapidly metabolized to its monoester (the active metabolite) and also glucuronidated, then excreted. The objective of this study is to evaluate the toxicity of phthalic acid (PA), which is the final common metabolic form of phthalic acid esters (PAEs). The individual PA isomers are extensively employed in the synthesis of synthetic agents, for example isophthalic acid (IPA), and terephthalic acid (TPA), which have very broad applications in the preparation of phthalate ester plasticizers and components of polyester fiber, film and fabricated items. There is a broad potential for exposure by industrial workers during the manufacturing process and by the general public (via vehicle exhausts, consumer products, etc). This review suggests that PA shows in vitro and in vivo toxicity (mutagenicity, developmental toxicity, reproductive toxicity, etc.). In addition, PA seems to be a useful biomarker for multiple exposure to PAEs in humans.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.269-277
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• 1998

This in vitro study compared the microleakage of 4 lining conditions when used with Gallium alloy GF II and Valiant PhD. Class V cavity was prepared on both buccal and lingual surface of 80 extracted human premolar & molar teeth with one margin in enamel and another in dentin. Before restoration, prepared cavities were applied to no-liner, cavity varnish, Scotchbond multipurpose, and Superbond D-liner II plus according to manufacture's instructions. The restored teeth were stored in saline for 1 week, then thermocycled for 100 times, stained with 0.5% basic fuchsin dye for 1 day, sectioned, and observed using a light microscope. Following results were obtained. 1. The leakage value of Superbond-lined group showed significantly lower than that of nolined group on both margins of Valiant PhD(p<0.05). 2; There was no significant difference between the 4 lining conditions in Gallium alloy GF II (p>0.05). 3. When We make a comparison between Gallium alloy GF II and Valiant PhD under same lining conditions, the microleakage value of Gallium alloy GF II showed lower than that of Valiant PhD on occlusal & gingival margin(p<0.05) except for Superbond-lined group(p>0.05).

• The Korean Journal of Oral and Maxillofacial Pathology
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• v.42 no.6
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• pp.183-187
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• 2018

The supernumerary tooth which is extra tooth in comparison to normal dentition is one of the developmental problems. The most common type of supernumerary tooth is mesiodens which may cause several complications like delayed eruption, crowding, spacing et al. Moral Incisor Hypomineralization (MIH) describes the clinical appearance of enamel hypomineralization of systemic origin affecting one or more permanent first molars that associated frequently with affected incisors. We report a case of a 6 - year - old boy who visited our clinic for removal of mesiodentes. The patient was diagnosed by mesiodentes and MIH by clinical examination and radiographic examination. Under local anesthesia, Mesiodentes were removed surgically. The demarcated opacities, a feature of MIH, were observed in the removed mesiodentes. After removal of mesiodentes, the maxillary central incisors erupted normally and in order to manage the teeth affected MIH, follow-up and fluoride varnish application were done every 3 months.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.5 no.2
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• pp.87-91
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• 2009

The purpose of this study were to investigate the chief complain and dental treatment needs in handicapped patient. This study examines treatment records of 1025 patients in free dental clinic for handicapped patients during 10 years from 1999 to 2008. The results were as follows : 5.8 average visit per patient; mean patient age was 25; 544 patients was younger than 20. Handicapped patients classified according to types of disability. Crippled disorder were 19.1%, brain disorder were 4.5%, visual disorder were 3.1%, auditory disorder were 4.1%, speech disorder were 0.9%, mental retardation were 67.1%, and developmental disorder were 25.1%. Performed treatments were 322 scaling, 13 fluoride varnish, 727 preventive resin restoration, 1296 resin restoration, 600 amalgam restoration, 46 GI restoration, 612 extraction, 289 pulp treatment of primary teeth, 75 pulp treatment of permanent teeth and 138 stainless steel crown restoration. Many handicapped patients have some difficulty to dental treatment. They have limited access to dental care, which is compounded by a shortage of skilled dental professionals who are willing to treat these population and financial problems.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.394-402
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• 2002

2급 복합레진 수복 와동의 치은 변연이 상아질 상에 있을 때 유동성 레진 이장의 유무와 두께가 미세누출에 미치는 영향을 알아보기 위해 본 실험을 시행하였다. 60개의 발거된 대구치의 근, 원심면에 각각 협설측 3mm, 치은벽 깊이 1mm의 2급 와동을 형성하고 치은 변연은 법랑-백아 경계에서 약 1mm 하방에 위치 시켰다. 모든 와동을 32% 인산으로 15초 처리 및 30초 수세 후 Prime & Bond$^{\circledR}$ NT 상아질 접착제를 적용하였고, Tetric Ceram(TC), Tetric Flow(TF)를 이용하여 다음의 6가지 군으로 나누어 수복하였다. (1) TC로 수평 적층 충전, (2) TC로 수직 적층 충전, (3) 0.5-1mm두께로 TF 이장 후 TC로 수평적층 충전, (4) 0.5-1mm 두께로 TF 이장 후 TC로 수직 적층 충전, (5) 2-3mm 두께로 TF 이장 후 TC로 수평적층 충전, (6) 2-3mm두께로 TF이장 후 TC로 수직 적층 충전. 충전된 시편을 37$^{\circ}C$ 100% humidity에서 24시간 보관하고 5$^{\circ}C$와 55$^{\circ}C$에서 500회의 열순환을 실시하여 치은 변연의 0.5mm 외부에 nail varnish를 도포 하여 2% methylene blue 용액에 12시간 침잠시켰다. 시편을 아크릴릭 레진에 매몰하여 수복물의 중앙에서 종절단 한 후 입체현미경하에서 색소의 침투도를 관찰하여 다음과 같은 결과를 얻었다. 유동성 레진의 이장을 시행한 군과 하지 않은 군간에 미세누출은 유의차를 보이지 않았다(p>0.05) 유동성 레진의 두께에 따른 미세누출의 차이는 나타나지 않았다(p>0.05) 경사면 충전법을 시행한 군에서는 유동성 레진을 이장한 군들이 이장하지 않은 군보다 유의하게 많은 누출을 보였다(p<0.05). 수평적층 충전법을 시행한 군에서는 유동성 레진 이장이 미세누출에 유의한 차이를 보이지 않았다(p>0.05).

• Journal of Korean society of Dental Hygiene
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• v.10 no.3
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• pp.473-481
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• 2010

Objectives : To evaluate the effect of fluoride application on the color and microhardness of bleached enamel and compare it to that of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application. Methods : Twenty freshly extracted human adult molar were each sectioned into halves, the specimens divided and treated according to five experimental groups: Group 1, treatment with 10% carbamide peroxide (CP) bleaching agent; Group 2, treatment with 10% CP followed by a 1.23% fluoride gel application; Group 3, treatment with 10% CP followed by a 2.23% sodium fluoride varnish application; Group 4, treatment with 10% CP followed by a 0.11% sodium fluoride gel application; Group 5, treatment with 10% CP followed by a CPP-ACP gel application. All groups were treated 6 h per day for 14 days then immersed in distilled water for 2 weeks. Changes in enamel color were evaluated on Baseline and Day 14. Microhardness were evaluated on Baseline, Days 7 and 14. Statistical analysis was performed using one-way ANOVA and post-hoc Tukey tests. Results : All the bleached enamel specimens revealed increased whiteness and overall color value. Group 1 showed the lowest microhardness values than that of Groups 2, 3, 4 and 5. In all groups, the hardness of tooth after bleaching showed a significant decrease in the microhardness as compared with the one prior to tooth bleaching. The specimens treated with remineralizing agents showed relatively less reduction in enamel microhardness than control group. Conclusions : The addition of fluoride and CPP-ACP did not impede the whitening effect. The use of remineralizing agents during bleaching treatment can significantly enhance the microhardness of bleached enamel.

• Bulletin of the Society of Naval Architects of Korea
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• v.4 no.1
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• pp.49-54
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• 1967

The authors considered the effects of trim in the small coastal passenger boat upon resistance in this paper. Any change of trim no matter how small, necessarily produces some effect upon resistance. The relations between the resistance coefficients and trim were investigated through the towing test of the Model $MCI-P_1-65$, Korean Standardized Ship, GT 70 tons passenger boat in the gravitational tank. The Lines of the Model are given in Fig. 1. Principal dimensions and other characteristics vary with the trim in general. Those values varied with the trim for $MCI-P_1-65$ are tabulated in table 1. The resistance was measured at five conditions such as even keel, 0.0273L, (original designed trim) 0.0473L, 0.0663L, 0.0873L trim by the stern, fixing the displacement corresponding to the designed load water line. Model was made of wood in length of 3.5 feet coated with varnish, and without appendages. As the artificial turbulent stimulator, the sand strip method was used. The results of model towing tests, correcting to water temperature of $70^{\circ}F$, were expanded to full scale using the Schoenherr's friction formula and surface roughness allowance coefficient of 0.0004. The authors point out, the following results. 1) Optimum trim which gives the minimum resistance exists for every speed at constant displacement and each comes to the same value. For $MCI-P_1-65$ optimum trim is 0.0673L trim by the stern(Fig.4-The cross curves of the resistancecoefficients). 2) At constant displacement, when LCB(longitudinal position of center of buoyancy) varies with the trim, there exists optimum value of LCB which gives minimum resistance for every speed and each comes to the same value. For $MCI-P_1-65$ optimum position of LCB is 8%L aft from midship section (Fig.6).

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.103-110
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• 2013

Lacquer has traditionally been used to varnish. Many reports have revealed that lacquer has anti-microbical, anti-cancer, and anti-inflammatory activities. However, urushiol and their derivatives were known as an allergen. Therefore, we expected that lacquer will be used as a good health-food source if its side effect was solved. Here we analyzed their allergy induced constituents by using the GC/MS and evaluated comparative concentration of lacquer, puerariae radix and their mixture extracts. Our results showed that lacquer extract has allergenic compounds and mixture extract with puerariae radix has relatively lower amount. However, lacquer/puerariae mixture extract has strong anti-allergenic effects on the RBL-2H3 cell and puerariae extract was blocked allergenic effect caused by allergenic constituents contained in lacquer.

• Imaging Science in Dentistry
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• v.42 no.1
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• pp.19-24
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• 2012

Purpose : Field of view and voxel resolution of cone beam computed tomography (CBCT) might affect the diagnostic capability. This study was performed to compare between the standard and HiRes zoom modes in the diagnosis of external root resorption (ERR) using CBCT. Materials and Methods : Sixty three small cavities (0.25 mm depth and 0.5 mm diameter) were simulated on the buccal, lingual, and proximal surfaces at three different levels of 16 roots of teeth. After covering the root with nail varnish, the roots were inserted in the sockets and the model was placed in a water-containing lacuna. CBCT scans were taken in both standard and HiRes zoom modes using NewTom VG (QR srl Company, Verona, Italy). Then, an observer assessed the images to determine the presence or absence of the cavities. This process was repeated by increasing the size and depth of cavities to 0.5 mm depth and 1 mm diameter. Data were analyzed by McNemar test. The sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio in evaluation of the simulated cavities were calculated. Results : There was a significant difference between the two imaging modes in diagnosing the shallow cavities (p=0.02).The sensitivity of the standard zoom in detecting the shallow cavities was lower than that of the HiRes zoom. The likelihood ratio of the HiRes zoom was higher in the diagnosis of both cavity types. Conclusion : This study suggested that a smaller voxel size in the HiRes zoom mode of CBCT is preferred for diagnosis of ERR.