• Restorative Dentistry and Endodontics
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• 제24권4호
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• pp.546-553
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• 1999

In Older to evaluate the effectiveness of 'One-bottle dentin adhesive system', the shear bond strengths of two fourth generation dentin adhesive systems and two One-bottle systems to the occlusal dentin of the freshly extracted third molars were measured by the regulation of the ISO TR 11405. The fourth generation dentin adhesive systems used in this study were Scotchbond Multi-Purpose Plus and All-Bond 2, and the One-bottle systems were Single Bond and One-Step. The effects of the thickness of hybrid layer and adhesive layer, the diameter of resin tag and the ratio between the diameter of resin tag and that of dentinal tubule were analyzed as the contributing factors of the shear bond strength of dentin bonding systems from the Scanning Electron Microscopic images. The results were as follows: 1. The shear bond strengths of Scotchbond Multi-Purpose, All-Bond 2, and Single Bond were 16.98${\pm}$3.40 MPa, 15.10${\pm}$2.77 MPa and 15.05${\pm}$3.18 MPa, respectively. There were no statistical differences(p>0.05). 2. But, the shear bond strength of One-Step were significantly lower than those of the other groups (11.81${\pm}$1.95 MPa, p<0.05). 3. The thicknesses of hybrid layer and adhesive layer of One-Step were significantly thinner than those of the other groups(p<0.05). The differences of the diameter of resin tag(p=0.0685) and the ratio between the diameter of resin tag and that of dentinal tubule(p=0.2401) were not significant among all the material groups. 4. The thickness of hybrid layer and adhesive layer might be considered as contributing factors of the she at bond strengths of dentin bonding systems, but the diameter of resin tag and the ratio between the diameter of resin tag and that of dentinal tubule might not.

• 대한소아치과학회지
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• 제28권4호
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• pp.553-565
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• 2001

새로운 상아질 결합제인 5세대 상아질 결합제는 산 부식, 전 처치, 그리고 접착의 복잡한 과정을 줄여줌으로써 시술 과정이 간단하고 시간이 단축되며 시술 도중의 오염에 대한 가능성을 줄여준다는 점에서 유용성이 부각되고 있다. One-bottle 상아질 결합제에 관한 기존의 연구들이 아세톤, 에탄올 등의 용매를 포함하는 상아질 결합제를 중심으로 이루어져 본 실험에서는 water-based 상아질 결합제를 우치(牛齒)의 상아질에 적용하여 얻어지는 상아질 결합력을 전단 결합 강도 측정과 주사 전자현미경 관찰을 통해 다음과 같은 결론을 얻었다. 1. 전단결합강도의 측정결과 II군 IV군, I군, III군의 순서로 II군에서 다소 높은 전단강도를 보였으나, 모든 군들간에는 유의 차가 없었다(p>0.05). 2. 주사 전자 현미경 소견에서 II군과 IV군에서 서로 유사한 양상의 잘 형성된 혼화층이 관찰되었으며 레진 테그의 측방 가지 또한 다수 관찰할 수 있었다.

• Restorative Dentistry and Endodontics
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• 제29권6호
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• pp.504-514
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• 2004

LED 광중합기(Elipar FreeLight, 3M-ESPE)와 할로겐 광중합기(VIP Bisco)로 광조사한 수종의 상아질 접착제에 대해서 상아질 전단접착강도를 비교하였다 또한 이번 연구의 광학적 근거를 얻기 위해 두 광중합기의 파장에 따른 광강도와 스펙트럼을 비교하였다. 이번 연구에서 사용된 상아질 접착제는 Scotchbond Multipurpose (3M ESPE), Single Bond (3M ESPE). One-Step (Bisco), Clearfil SE Bond (Kuraray), Adper Prompt (3M ESPE) 이다. VIP는 487 nm에서 최대정점을 가지는 넓은 스펙트럼의 분포를 보이는 반면에, Elipar FreeLight는 465 nm에서의 최대정점을 중심으로 좁은 스펙트럼의 분포를 보였다. Clearfil SE bond를 제외하고 할로겐과 LED로 광조사 한 각 상아질 접착제에서 상아질 전단접착강도값의 유의성 있는 차이는 보이지 않았다 (P > 0.05). 이러한 결과는 camphoroquinone의 흡수스펙트럼과 LED의 좁은 영역의 스펙트럼사이에 강한 연관성으로 설명할 수 있다.

• Restorative Dentistry and Endodontics
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• 제30권4호
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• pp.319-326
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• 2005

본 연구는 단일 단계 접착제의 표층과 심층 상아질에 대한 미세인장 결합강도의 차이를 평가하기 위해서 시행되었다. 발거된 상$\cdot$하악 대구치의 교합면측에 있는 표층 상아질과 심층 상아질을 각각 15개씩 노출시킨 후, 사용된 접착제에 따라 AQ군, L-Pop군, Xeno군으로 분류하여 복합레진을 축조하였다. 각 시편은 상아질과 복합레진 계면의 단면적이 $1.0mm^2$이 되도록 절단하였고, 각 군 당 20개의 시편을 사용하였다. 각 군의 미세인장 결합강도의 측정하여 다음과 같은 결과를 얻었다. 표층과 심층 상아질 모두에서 Xeno III는 다른 접착제보다 가장 높은 결합강도를 나타내었다 (p<0.05). 또한 모든 접착제는 심층 상아질에서 보다 표층 상아질에서 더 높은 결합강도를 나타내었으나 이들 간에 통계학적 인 유의성은 접착제의 종류에 따라 다르게 나타났다.

• Restorative Dentistry and Endodontics
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• 제46권3호
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• pp.32.1-32.10
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• 2021

Objectives: This study aimed to evaluate the effect of the application method of universal adhesives on the shear bond strength (SBS) of repaired composites, applied with different thicknesses. Materials and Methods: The 84 specimens (Filtek Z350 XT) were prepared, stored in distilled water for a week and thermocycled (5,000 cycles, 5℃ to 55℃). They were roughened using 400-grit sandpapers and etched with phosphoric acid. Then, specimens were equally divided into 2 groups; Single Bond Universal (SU) and Prime&Bond Universal (PB). Each group was subdivided into 3 subgroups according to application methods (n = 14); UC: 1 coat + uncuring, 1C: 1 coat + curing, 3C: 3 coats + curing. After storage of the repaired composite for 24 hours, specimens were subjected to the SBS test and the data were statistically analyzed by 2-way analysis of variance and independent t-tests. Specimens were examined with a stereomicroscope to analyze fracture mode and a scanning electron microscope to observe the interface. Results: Adhesive material was a significant factor (p = 0.001). Bond strengths with SU were higher than PB. The highest strength was obtained from the 1C group with SU. Bonding in multiple layers increased adhesive thicknesses, but there was no significant difference in SBS values (p = 0.255). Failure mode was predominantly cohesive in old composites. Conclusions: The application of an adequate bonding system plays an important role in repairing composite resin. SU showed higher SBS than PB and the additional layers increased the adhesive thickness without affecting SBS.

• Communications for Statistical Applications and Methods
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• 제16권3호
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• pp.487-493
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• 2009

We consider a multiple defaultable zero coupon bond. Assuming defaults occur according to a marked point process, we explain how to estimate the time-t discounted price of zero coupon bond by simulation. For the special case of a given specific random face value, we show that the real probability measure is the risk neutral probability measure. In this case the time-t discounted conditional price can be obtained by observing a single sample path upto the time t in the real world. Furthermore the time-t discounted price can be estimated by observing real situations or by simulation under the real probability measure.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.238-239
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• 2014

It is well known that the bond characteristics of fiber govern the performance of fiber reinforced composite material. A preliminary study was carried out to investigate the pull-out behavior of amorphous and conventional single fiber in cement mortar in accordance with the JCI(Japan Concrete Institute) SF-8. The test was performed under displacement control, and results showed that the bond strength decreased with increasing fiber length. In addition, the amorphous steel fiber showed much higher pull-out load per unit weight compared to conventional steel fiber.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.576-577
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• 2003

I. Objectives This study investigated the dentin shear bond strength and the degree of conversion (DC) of currently used dentin bonding agents (DBAs) that were irradiated with a light emitting diode (LED) light curing unit (LCU) and a halogen LCU. II. Materials and methods The halogen LCU and the LED LCU used in this study were a VIP(Bisco, Schaumburg, IL, USA) and an Elipar Freelight(3M ESPE, St Paul, MN, USA) respectively. For the VIP, $400mW{\cdot}cm-2$ intensity mode was used to adjust to the intensity of the LED LCU. The DBAs used in this study were Scotchbond Multipurpose (3M ESPE), Single Bond (3M ESPE), One-step(Bisco), Clearfil SE Bond(Kuraray), and Adper Prompt(3M ESPE).(omitted)

• Restorative Dentistry and Endodontics
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• 제36권1호
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• pp.50-58
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• 2011

연구목적: 이 연구는 2종의 전부식 접착제와 4종의 자가부식 접착제를 이용하여 유동성 레진을 법랑질에 접착할 경우, 접착제에 따른 미세전단 결합강도와 파절양상을 비교하기 위하여 시행하였다. 연구 재료 및 방법: 발거된 60개의 대구치 치관의 법랑질을 이용하였고, 사용된 접착시스템의 종류에 따라 6개의 군; OS 군(One-Step), SB 군(Single Bond), SE 군(Clearfil SE Bond), TY 군(Tyrian SPE와 One-Step Plus), AP 군(Adper prompt L-Pop), GB 군(G-Bond)으로 분류하였다. 각 군의 법랑질 표면에 배정된 접착시스템을 적용한 후, Tygon tube를 이용하여 법랑질 표면에 유동성 레진(Filtek Z 350 flowable resin)을 접착하였다. 각 군의 미세전단 결합강도를 측정한 후 주사전자현미경하에서 파절양상을 비교하였다. 결과: 1. SB 군의 결합강도는 다른 모든 군보다 통계학적으로 높게 나타났고, GB 군의 결합강도는 다른 모든 군의 결합강도 보다 통계학적으로 낮게 나타났다(p < 0.05). 2. OS 군과 SE 군 및 AP 군의 결합강도는 SB 군보다 낮게 나타났지만, TY 군과 GB 군보다 통계학적으로 높게 나타났다(p < 0.05). 3. TY 군의 결합강도는 GB 군보다 통계학적으로 높게 나타났다(p < 0.05). 4. 접착성 파절은 TY 군과 GB 군에서 가장 많이 나타났고, 혼합파절은 SB 군과 SE 군에서 가장 많이 나타났으며, 응집성 파절은 OS 군, SB 군, SE 군 및 AP 군에서 각각 1개씩 나타났다. 결론: 접착 단계가 같은 접착시스템이라 해도 법랑질에 대한 유동성 레진의 미세전단 결합강도는 서로 다르게 나타났다.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.22.1-22.12
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• 2021

Objectives: This study evaluated and compared the effects of radiation therapy on the dislocation resistance of AH Plus and BioRoot RCS applied to dentin and the sealer-dentin interface. Materials and Methods: Thirty single-rooted teeth were randomly assigned to 2 groups (n = 15 each): AH Plus (Dentsply DeTrey) and BioRoot RCS (Septodont). Each group was subdivided into control and experimental groups. The experimental group was subjected to a total radiation dose of 60 Gy. The root canals of all samples were cleaned, shaped, and obturated using the single-cone technique. Dentin slices (1 mm) were sectioned from each root third for the push-out test and scanning electron microscopy (SEM) was done to examine the sealer-dentin interface. The failure mode was determined using stereomicroscopy. Bond strength data were analyzed by the independent t-test, 1-way analysis of variance, and the Tukey post hoc test (α = 0.05). Results: Significantly lower bond strength was observed in irradiated teeth than non-irradiated teeth in the AH Plus group (p < 0.05). The BioRoot RCS group showed no significant reduction in bond strength after irradiation (p > 0.05) and showed a higher post-irradiation bond strength (209.92 ± 172.26 MPa) than the AH Plus group. SEM revealed slightly larger gap-containing regions in irradiated specimens from both groups. Conclusions: The dislocation resistance of BioRoot RCS was not significantly changed by irradiation and was higher than that of AH Plus. BioRoot RCS may be the sealer of choice for root canal treatment in patients undergoing radiation therapy.