• 대한소아치과학회지
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• 제39권2호
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• pp.153-159
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• 2012

본 연구는 치면열구전색술의 시술과정에 발생될 수 있는 타액오염이 치면열구전색제의 전단결합강도에 미치는 영향을 알아보고자 하였으며, 수종의 접착제를 이용하였을 경우, 각 단계의 타액오염이 통상적인 치면열구전색술에서의 전단결합강도와의 차이를 알아보고자 하였다. 56개의 우식이 없는 발치된 치아를 이용하여 시행하였으며, 3개의 군에서 타액오염을 시키는 술식단계에 따라 다음과 같이 7개의 군으로 나누어 실험을 시행하였다. 각 군을 산부식만 시행한 경우(Group A와 B), Adper$^{TM}$ Single Bond를 적용한 경우(Group C, D, E), Adper$^{TM}$ Prompt L-pop을 적용한 경우(Group F, G)로 나누어 실험군의 치면에 타액을 10초간 적용하였다. 치면열구전색제를 적용시키고 열순환을 시행하였으며, 전단결합강도를 측정하여 다음과 같은 결과를 얻었다. 1. 통상적인 치면열구전색술에서는 타액오염시 전단결합강도가 유의성 있게 감소하였다(p<0.05). 그러나, 접착제를 적용한 뒤 치면열구 전색술을 시행한 군에서는 접착제의 종류나 오염을 시킨 단계에 따른 유의성있는 차이는 나타나지 않았다. 2. 타액오염을 시키지 않고 치면열구전색술을 시행한 군들에서는 Adper$^{TM}$ Single Bond가 높은 결합강도를 보였으나 유의성있는 차이를 보이지 않았다. 3. 파절편 검사결과 접착제를 사용한 대부분의 군들에서 응집성 파절이 관찰된 반면 접착제를 사용하지 않은 군들에서는 접착성 파절이 관찰되었다.

• EDISON SW 활용 경진대회 논문집
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• 제5회(2016년)
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• pp.155-162
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• 2016

This study attempts to reveal structures of two-dimensional ring polymer solutions in various polymer concentrations ranging from dilute to concentrated regime. Polymer sizes, single molecule structure factors, bond correlation functions and monomer density distribution functions from center of mass are given in order to clarify the polymer structures. Our study shows that a ring in dilute solution maintain pseudo-circular structure with self-avoiding walk (SAW) statistics, and it seems to be composed of two connecting SAW linear chains. In semidilute solutions, ring polymers are not entangled with each other and adopt collapsed configurations. Such assumption of collapsed structures in the semidilute regime gives an overlap concentration of ${\varphi}^*{\sim}N^{-1/2}$ where N is degree of polymerization. By normalizing the polymer concentration by these overlap concentration, we find universal behaviors of polymer sizes and structure factors regardless of N.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.568-568
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• 2003

I. Objectives This study investigated the effect of rewetting agent on dentinal microtensile bond strengths(${\mu}TBS$), using one bottle adhesives. II. Materials and Methods Non caries human molars were sectioned to exposed the superficial dentin surfaces, etched 15 seconds using 32% phosphoric acid and 10 seconds rinsed. Samples were randomly divided into two groups according to adhesives (Single Bond, One-Step) used. Each group were subdivided into five groups by different dentin surface treatment：15 second dry(D), blot dry(BD) or 15 second dry and rewetted with distrilled water(DW), Gluma Desensitizer(GD) and Aqua-Prep(AP) during 30 second, respectively.(omitted)

• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.880-886
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• 1997

Ab initio calculations were carried out on the gas phase acid-catalyzed hydrolysis reactions of sulfinamide using the 3-21G* basis sets. Single point calculations were also performed at the MP2/6-31G* level. The first step in the acid-catalyzed hydrolysis of N-methylmethanesulfinamide, Ⅰ, involves protonation. The most favorable form is the O-protonated one, Ⅱ, which is then transformed into a sulfurane intermediate, Ⅲ, by addition of a water molecule. The reaction proceeds further by an intramolecular proton transfer from O to N (TS2), which is followed by N-S bond cleavage (TS3) leading to the final products. The rate determining step is the N-S bond cleavage (TS3) at the RHF/3-21G* level, whereas it becomes indeterminable at the MP2/6-31G*//3-21G* level of theory. However, the substituent effect studies with N-protonated N-arylmethanesulfinamide, ⅩⅢ, at the MP2/6-31G*//3-21G* level support the N-S bond breaking step as rate limiting.

• Restorative Dentistry and Endodontics
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• 제35권3호
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• pp.211-221
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• 2010

본 연구는 상아질의 비교원성 단백질을 chondroitinase ABC (C-ABC)를 이용하여 제거함으로써 비교원성 단백질의 제거가 상아질 접착제의 미세인장결합강도와 교원질망의 형태에 미치는 영향을 상아질의 다양한 습윤상태에 따라 평가하고자 시행하였다. 비교원성 단백질의 상아질접착제의 미세인장강도에 대한 영향을 평가하기 위해 제 3대구치의 상아질을 노출시키고, 두 군으로 나누고 한 군은 C-ABC, 다른 군은 증류수를 $37^{\circ}C$에서 48시간 동안 적용한 후, 상아질의 습윤상태(wet, dry 및 re-wet)와 상아질 접착제(Single Bond 2, One Step Plus)를 다르게 이용하여 복합레진을 수복하였다. 24시간 후 가로 1 mm, 세로 1mm의 시편을 제작하고 미세인장강도를 측정하였다. 상아질 교원질의 형태변화를 관찰하기 위하여 상아질 시편에 산부식을 시행하고 C-ABC 적용 후, 시편을 제작하였고 미세인장강도 측정후 파괴된 접착면의 파괴양상과 각 접착제의 접착계면 관찰을 위하여 FE-SEM 관찰하였다. C-ABC 처리여부와 관계없이 습윤한 상아질면에 접착한 군은 모든 접착제에서 통계학적으로 유의성있는 미세인장결합강도의 차이를 나타나지 않았다(p > 0.05). C-ABC를 적용하였을 경우, Single Bond 2에서는 재수화한 상아질면에 접착한 군이 습윤한 상아질면에 접착한 군에 비해 미세인장결합강도가 감소하였다(p < 0.05). FE-SEM 관찰결과, C-ABC를 적용후에는 접착성 파괴가 주로 일어났으며, 교원질 섬유간 거리가 증가하였으며 부분적으로 교원질 섬유들간에 응집된 양상이 관찰되었다.

• 한국산학기술학회논문지
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• 제13권4호
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• pp.1453-1459
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• 2012

본 연구에서는 보이스코일 모터와 압전 구동기를 동일 축으로 배치함으로써 초정밀 위치결정뿐만 아니라 동특성을 개선할 수 있도록 하는 듀얼 스테이지를 다룬다. 듀얼 스테이지는 모델링이 엉성할 경우 오히려 나쁜 동특성을 보이는 단점이 있다. 이 논문은 본드그래프를 이용하여 듀얼 스테이지를 모델링하고 동적 상태방정식을 본드그래프에서 유도하였다. 또한 동특성을 향상시키기 위한 보상기의 설계 예시를 보이고 있으며, 시뮬레이션을 통해 검증하였다.

• Restorative Dentistry and Endodontics
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• 제24권1호
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• pp.55-66
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• 1999

The purpose of this study was to evaluate the microleakage of 5 current dentin bonding systems which are composed of 2 multi-bottle systems(Scotchbond Multi-Purpose, All Bond2) and 3 one-bottle systems(Single bond, One-Step, Prime & Bond). In this in vitro study, class V cavities were prepared on buccal and lingual surfaces of sixty extracted human premolars and molars on cementum margin. The experimental teeth were randomly divided into six groups of 10 samples (20 surfaces) each, Group 1 : Scotchbond Multi-Purpose ; Group 2 : All Bond 2 ; Group 3 : Single Bond ; Group 4 : One-Step ; Group 5 : Prime & Bond ; Group 6 : no bonding agent(control). The bonding agent and composite resin were applied for each group following the manufacturer's instructions. After 500 thermocycling between $5^{\circ}C$ and $55^{\circ}C$, the 60 teeth were placed in 2% Methylene blue dye for 24 hours, then rinsed with tab water. The specimen were embedded in clear resin, then sectioned buccolingually through the center of restoration with a low speed diamond saw. The dye penetration on each of the specimen were then observed with a stereomicroscope at ${\times}20$. The results of study were statistically analyzed using the Student-Newmann-Keul's Methods and the Mann-Whitney Rank Sum Test. The resin/dentin interfaces were examined under Scanning Electron Microscopy. The results of this study were as follows. 1. None of the dentin bonding systems used in this study showed significant difference in leakage values at both the enamel and the dentin margins (P>0.05). 2. In all groups except the control, leakage value seen at the enamel margin was significantly lower than that seen at the dentin margin (P<0.05). 3. Compared to the control group, all the groups treated with dentin bonding systems showed significantly lower leakage value at both enamel and dentin margins (P<0.05). 4. In the SEM view, gaps were observed in the composite resin / dentin interface in group 6 where no dentin bonding agent was used, and in all the other groups (group 1, 2, 3, 4, 5) composite resin, hybrid layer, and dentin were seen to be closely adhering to each other where there were no leakages. Well-developed resin tags 3~100${\mu}m$ in length infiltrated dentinal tubules past the hybrid layer and a hybrid layer 1~5${\mu}m$ thick had developed between the dentinal surface and the composite resin surface.

• 대한소아치과학회지
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• 제30권1호
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• pp.143-152
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• 2003

본 연구는 자가부식 접착제의 치질로의 침투와 레진 tag 형성을 알아보고 부가적인 산부식이 레진 tag 형성에 미치는 효과를 관찰하기 위하여 계획되었다. 3종의 자가부식 접착제(SE bond, AQ bond and L Pop)와 one bottle adhesive(Single bond)를 사용하였고 발거한 구치로 교합면 법랑질과 상아질 시편을 제작하였으며 각 군당 5개씩 네 개의 군으로 나눈 총 20개의 시편을 양분하여 각각 접착제를 적용하기 전 35% 인산으로 산부식하거나 산부식처리하지 않았으며 이후 레진을 적용시키고 중합하였다. 시편은 Silverstone microtome으로 절단한 후 HCl 용액과 NaOCl 용액으로 처리하고 건조시킨 후 이온으로 피복하였으며 주사전자현미경으로 관찰하여 다음과 같은 결과를 얻었다. 1. 부가적 산부식 처리한 상아질은 모든 자가부식 접착제군에서 산부식하지 않은 상아질보다 resin tag의 길이와 두께가 증가하는 것이 관찰되었다. 2. 법랑질에서는 L Pop을 제외하고 부가적 산부식한 군에서 레진 tag의 두께가 산부식하지 않은 군보다 컸고 보다 명확한 부식양상을 관찰할 수 있었다. L Pop에서는 부식법랑질과 비부식법랑질간의 차이가 없었다. 본 연구의 결과는 자가부식형 접착제가 법랑질을 부식시키지 않고 상아세관으로 침투하는 정도가 산부식군에 미치지 못하다는 것을 의미한다. 이와 관련하여 접착강도와 미세누출 및 레진 tag 형태에 대한 부가적 연구가 필요할 것이다.

• Restorative Dentistry and Endodontics
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• 제39권2호
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• pp.95-103
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• 2014

Objectives: This study evaluated the effect of three antioxidizing agents on pullout bond strengths of dentin treated with sodium hypochlorite. Materials and Methods: Root canals of 75 single-rooted human teeth were prepared. Fifteen teeth were irrigated with normal saline for a negative control group, and the remaining 60 teeth (groups 2 - 5) with 2.5% NaOCl. The teeth in group 2 served as a positive control. Prior to post cementation, the root canals in groups 3 - 5 were irrigated with three antioxidizing agents including 10% rosmarinic acid (RA, Baridge essence), 10% hesperidin (HPN, Sigma), and 10% sodium ascorbate hydrogel (SA, AppliChem). Seventy-five spreaders (#55, taper .02, Produits Dentaires S.A) were coated with silica and silanized with the Rocatec system and ceramic bond. All the prepared spreaders were cemented with a self-adhesive resin cement (Bifix SE, Voco Gmbh) in the prepared canals. After storage in distilled water (24 h/$37^{\circ}C$), the spreaders were pulled out in a universal testing machine at a crosshead speed of 1.0 mm/min. Pull-out strength values were analyzed by one-way ANOVA and Tukey's HSD test (${\alpha}$ = 0.05). Results: There were significant differences between study groups (p = 0.016). The highest pullout strength was related to the SA group. The lowest strength was obtained in the positive control group. Conclusions: Irrigation with NaOCl during canal preparation decreased bond strength of resin cement to root dentin. Amongst the antioxidants tested, SA had superior results in reversing the diminishing effect of NaOCl irrigation on the bond strength to root dentin.

• Restorative Dentistry and Endodontics
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• 제28권3호
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• pp.203-208
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• 2003

The purpose of this study was to evaluate the effect of salivary contamination of teeth on bonding efficacy of self-priming and self-etching DBSs. The materials used were Single Bond(SB, self-priming system, 3M), Unifil Bond(UB, self-etching system, GC), and Scotchbond Multi-Purpose Plus(SM, 3M) as control. Forty five human molars randomly allocated to three groups as dentin bonding systems tested and embedded in epoxy resin. Then the specimens were wet-ground to expose flat buccal enamel surface or flat occlusal dentin surface and cut bucco-lingually to form two halves with slow speed diamond saw. One of them was used under non-contamination, other under contamination with saliva. The bonding procedure was according to the manufacturer's directions and resin composite(Z-100, 3M Dental Products, St. Paul, MN) was built-up on the bonded surface 5mm high. The specimens were ground carefully at the enamel-composite interface with fine finishing round diamond bur to create an hour-glass shape yielding bonded surface areas of $1.5{\pm}0.1\textrm{mm}^2$. The specimens were bonded to the modified microtensile testing apparatus with cyanoacrylate, attached to the universal testing machine and stressed in tension at a CHS of 1mm/min. The tensile force at failure was recorded and converted to a tensile stress(MPa). Mean values and standard deviations of the bond strength are listed in table. One-way ANOVA was used to determine significant difference at the 95% level. The bond strength of SBMP and SB were not affected by salivary contamination, but that of UB was significantly affected by salivary contamination. These results indicate that DBSs with total etch technique seems less likely affected by salivary contamination in bonding procedure.