• 대한치과기공학회지
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• 제35권2호
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• pp.121-126
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• 2013

Purpose: The aim of this research was to investigate difference in shear bond strengths of full-contour zirconia layered with porcelain. Methods: Disk-shaped (diameter: 12.0 mm; height: 3.0 mm) zirconia were randomly divided into six groups according to the surface conditioning method to be applied (N=90, n=15 per group): group 1-contol group(ZC); group 2-airborne particle abrasion with $50-{\mu}m\;Al_2O_3(5A)$; group $3-50-{\mu}m\;Al_2O_3$ + liner(5AL), group $4-110-{\mu}m\;Al_2O_3(1A)$; group $5-110-{\mu}m\;Al_2O_3$ + liner(1AL); group 6-liner(LC). On each block, zirconia porcelain was build up according to manufacturer's instructions. All samples were fixed with measuring jigs and shear bond strength were measured with Universal testing machine. Collected data were analyzed using SPSS(Statistical Package for Social Sciences) Win 12.0 statistics program. Results: LC showed the highest value($29.92{\pm}2.55$ MPa) and ZC showed the lowest value($13.22{\pm}1.37$ MPa). Zirconia liner and Alumina oxide groups was significantly higher shear bond strength than control(p<0.05). 5A (without liner $22.18{\pm}2.37$, with liner $22.84{\pm}1.74$ MPa) was higher shear bond strength than $110{\mu}m$ (without liner $20.18{\pm}2.38$, with $20.71{\pm}2.67$). Conclusion: Surface treatments may have advantage in bond strength improvement for full-contour zirconia layered with porcelain.

• The Journal of Advanced Prosthodontics
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• 제14권4호
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• pp.262-272
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• 2022

PURPOSE. This study aimed to analyze the shear bond strength between the 3D-printed denture base and the chairside relining material, according to the surface treatment. MATERIALS AND METHODS. Cylindrical specimens were prepared using DENTCA Denture Base II. The experimental groups were divided into 6 (n = 10): no surface treatment (C), Tokuyama Rebase II Normal adhesive (A), sandblasting (P), sandblasting and adhesive (PA), sandblasting and silane (PS), and the Rocatec system (PPS). After bonding the chairside relining material to the center of the specimens in a cylindrical shape, they were stored in distilled water for 24 hours. Shear bond strength was measured using a universal testing machine, and failure mode was analyzed with a scanning electron microscope. Shear bond strength values were analyzed using one-way analysis of variance, and Tukey's honest significant difference test was used for post-hoc analysis (P < .05). RESULTS. Group PPS exhibited significantly higher shear bond strength than all other groups. Groups P and PA displayed significantly higher bond strengths than the control group. There were no significant differences between groups PS and A compared to the control group. Regarding the failure mode, adhesive failure occurred primarily in groups C and A, and mixed failure mainly in groups P, PA, PS, and PPS. CONCLUSION. The shear bond strength between the 3D-printed denture base and the chairside relining material exhibited significant differences according to the surface treatment methods. It is believed that excellent adhesive strength will be obtained when the Rocatec system is applied to 3D-printed dentures in clinical practice.

• Restorative Dentistry and Endodontics
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• 제20권2호
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• pp.487-507
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• 1995

Composite resin repair requires strong bond strength between the new and old materials. The objective of the current study was to identify the optimal treatments for sufficient bond strengths. Bondings between same kinds of materials and cross bondings using chemical curing composites and light curing composites were tested. Surface treatments included the methods of sand-blasting, acid etching and coating of bonding agent. Seven kinds cases of combinations from three kinds of methods were experimented and compared with a control group of which surfaces were highly polished. Measurements of shear bond strength and observations of surface morphologic changes using a scanning electron microscope were done. Following conclusions were drawn : 1. The highest bond strength among composite resins were exhibited by the treatment of the sand-blasting and the coating of bonding agent. 2. Acid etched surfaces showed the lowest bond strength. Bond strengths obtained from experimental groups including acid etching were lower than those obtained from same kinds of experimental groups without acid etching. 3. Simple method of the coating of bonding agent produced the slightly increased bond strength on chemical curing composite and reduced bond strength on light curing composite. 4. Bonding surfaces of chemical curing composite resin showed slightly higher bond strengths than light curing composite resin, however significant differences were not confirmed statistically. 5. More significant irregular surfaces were created by sand-blasting method than acid etching method. 6. A principal component of fillers of both resins was silicon. Acid etching method produced the seperations and degradations of fillers, these were significant on light curing composite resins which containing barium fillers.

• 한국방재학회 논문집
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• 제9권1호
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• pp.27-32
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• 2009

본 연구의 주목적은 아스팔트 포장층간의 접착전단강도를 측정하는 실험법과 평가 방법을 개발하고 배수성 포장에 사용되는 택코트 재료의 특성과 적정 살포량을 평가하고자 하였다. 실험에는 두 종류(RSC-4, 개질유화)의 유화아스팔트와 가열 아스팔트바인더 타입(HM-1) 한 종류로 실시하였으며, HM-1은 배수성 포장에 사용하기 위해 새로 개발된 제품이다. 접착전단강도를 측정하기 위해 직접전단실험을 다양한 실험 조건에서 수행하였다. 실험을 통해 얻은 접착전단강도 값은 결과의 변별력이 떨어 졌으며 하중-변위 곡선의 면적인 터프니스가 접착전단강도를 평가하는데 보다 유용한 것을 확인 할 수 있었다. 배수성 포장의 경우 RSC-4의 경우는 $0.8l/m^2$ 이상, 개질유화아스팔트의 경우는 $0.5{\sim}0.6l/m^2$의 살포량이 적당한 것으로 나타났다. Trackless 성능이 우수한 HM-1은 유화 아스팔트 택코트에 비해 월등히 좋은 접착전단성능을 발휘하는 것으로 나타났다.

• 대한치과보철학회지
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• 제31권2호
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• pp.181-190
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• 1993

The purpose of this study was to evaluate the effect of shear bond strength between various percentage of reused dental ceramic alloys and porcelain. One hundred specimens were made of one semiprecious alloy and three nonprecious alloys. Each alloy group was subdevided into five groups according to the additional precentage of new alloy. Group I specimens were made of 100% new alloy and served as the control of the investigation. Group II specimens were made of once-cast alloy with 75% new alloy. Group III specimens were made of once-cast alloy with 50% new alloy. Group IV specimens were made of once-cast alloy with 25% new alloy. Group V specimens were made of 100% recast alloy. Five specimens were made for each group of the alloy combinations. The test specimens were prepared by firing porcelain doughnuts on the alloy rod surface, and invested in dental stone. Bond strengths were measured by Instron universal testing machine at a crosshead speed of 0.5mm/min. The fractured surface of metal specimens were examined under the scanning electron microscope. The obtained results were as follows : 1. The shear bond strength of Albabond showed no significant difference between control group and reused alloy group. 2. The shear bond strength of reused alloy groups of nonprecious alloys were lower than that of control groups. 3. The shear bond strength between porcelain and metal in semiprecious alloy was higher than in nonprecious alloys 4. In nonprecious alloys. Rexillium III showed the highest bond strength value and Excelalloy showed the lowest shear bond strength value. 5. Regardless of the type of alloys and additional proportion of new alloys, scanning electron microscope photographs of the fracture surface between alloy and porcelain revealed simillar semiprecious alloy and nonprecious alloys.

• 대한소아치과학회지
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• 제30권1호
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• pp.47-53
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• 2003

본 연구는 영구치와 유치의 상아질 표면에 상품화된 화학기계적 우식치질 제거용액인 $Carisolv^{TM}$(MediTeam, Sweden)를 사용하고 복합레진을 접착한 후 전단결합강도를 측정함으로써 $Carisolv^{TM}$의 사용이 복합레진의 접착에 미치는 영향을 평가하고자 하였다. 교정치료를 위하여 발거된 상, 하악 소구치 80개와 정상적으로 탈락한 손상이 없이 건전한 상악 유전치 80개의 순, 협면의 상아질을 노출시키고 $Carisolv^{TM}$를 실험군은 60초 적용하고 대조군은 $Carisolv^{TM}$를 사용하지 않았다. 상아질 접착제는 Scotchbond Multi-Purpose(3M, USA), Single Bond(3M, USA), Clearfil SE Bond(Kuraray, Japan), AQ Bond(Sun Medical, Japan)를 각각 제조사의 지시대로 적용하였고 광중합형 복합레진은 Z100(3M, USA)을 사용하였다. $5^{\circ}C$와 $55^{\circ}C$에 각 30초씩 계류시켜 1,000회 열순환시키고 Universal Testing Machine(Zwick Z020, Zwick Co., Germany)을 사용하여 전단결합강도를 측정하고 분석하여 다음과 같은 결론을 얻었다. 1. 각 군간 전단결합강도를 비교한 결과, 유치에 비해 영구치의 전단결합강도가 높게 나타났다. 영구치에서는 Clearfil SE Bond만 사용한 군에서 가장 높았고 $Carisolv^{TM}$와 AQ Bond를 병용한 군에서 가장 낮았다. 2. $Carisolv^{TM}$ 사용하지 않은 군과 사용한 군간의 전단결합강도를 비교한 결과, 영구치와 유치 모두에서 상아질 접착제의 종류에 관계없이 $Carisolv^{TM}$를 사용한 군이 사용하지 않은 군에 비해 전단결합강도가 통계학적으로 유의하게 낮게 나타났다(P<0.001). 3. 상아질 접착제의 종류에 따른 전단결합강도를 비교한 결과, 영구치와 유치 모두에서 Clearfil SE Bond를 사용한 군의 전단결합강도가 가장 높았으며 AQ Bond를 사용한 군의 전단결합강도가 가장 낮았다.

• 대한치과교정학회지
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• 제29권5호
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• pp.599-611
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• 1999

금속 브라켓의 결합강도에 영향을 미치는 요소인 브라켓 기저부의 형태와 결합 부위에 적용되는 힘의 특성에 대해 알아보고자 연구를 시행하였다. 형태가 다른 5종의 금속브라켓의 기저부와 결합강도 측정후 접착파절양상을 stereoscope and scanning electron microscope를 통해 관찰하고 결합 부위에 적용되는 힘은 전단결합강도, 인장결합강도, 전단/인장복합결합강도로 구분하고 결합강도를 비교하여 다음과 같은 결론을 얻었다. 1. 브라켓 기저부 형태에 따른 모든 군에서 전단결합강토(SBS)가 제일 컸으며, 인장결합강도(TBS)는 SBS의 50%정도 수준이었고 전단/인장복합결합강도(S/TBS)는 전단결합강도(SBS)의 30%정도이었다. 2. 브라켓의 결합강도는 Micro-Loc base가 가장 크고($SBS:22.86{\pm}1.37kgf,\;TBS:11.37{\pm}1.43kgf,\;S/TBS:6.69{\pm}0.34kgf$), Integral base가 가장 작았다($SBS:10.52{\pm}1.27kgf,\;TBS:4.27{\pm}1.08kgf,\;S/TBS:2.94{\pm}0.58kgf). 3. 단위면적당 결합강도 비교시, Integral base가 가장 작았고(p<0.05), 전단결합강도와 인장결합강도에서는 Micro-Loc과 Chessboard base간의 차이가 없었으며 (p>0.05), Non-Etched Foil Mesh와 Micro-Etched Foil Mesh base간의 전단결합강도와 인장결합강도는 차이가 없었으나, 전단/인장복합결합강도에서는 Micro-Etched Foil Mesh base가 Non-Etched Foil Mesh base보다 더 크게 나타났다. 4. 전단, 인장, 전단/인장복합결합강도 측정후 접착파절은 브라켓/레진 계면에서 일어나 ARI score가 작게 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.531-536
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• 2003

It is generally known that RC flexural members strengthened by GFRP(Glass Fiber Reinforced Polymers) tend to be failed by premature bond failure near the flexural-shear cracks happened at the mid-span of beams. It is therefore strongly recommended that premature bond failure must be avoided to insure the intended strengthening effects sufficiently. The various methodologies such as increasing bonded length of GFRP and bonding details including U-shape wrappings and epoxy shear-keys are examined in this study. The bonded length of GFRP are calculated based on the assumed bond strengths of epoxy saturating resin. Total six half scale RC beam specimens were constructed and tested to investigate the effectiveness of each methodologies to prevent the bond failure of GFRP. Test results of each specimens are discussed in this paper.

• 대한치과기공학회지
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• 제33권1호
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• pp.47-54
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• 2011

Purpose: To investigate shear bonding strength between dental zirconia ceramics with different surface treatment and metal bracket. Methods: Zirconia ceramics(LAVA, 3M ESPE, USA) were divided to 4 groups according to their surface treatment; no surface treatment(G1), sand blasting(G2), silane coating(G3), and sand blasting+silane coating(G4). Specimens were bonded to metal bracket using resin bond($Transbond^{TM}XT$, 3M Unitek, USA). Shear bond strength was measured using universal test machine(3366 INSTRON. U.S.A) with cross head speed of 1 mm/min. Microstructural investigation for fracture surface was performed after shear test. Results: Shear bonding strengths of single surface treatment groups (G2 and G3) were higher than no treatment group(G1). Combined Treatment Group (G4) showed the highest shear bond strength of 9.15MPa. Microstructural observation shows that higher shear bonding strength was obtained when debonding was occurred at metal bracket/resin interface rather than zirconia ceramic/resin interface. Conclusion: Surface treatment of zirconia is necessary to obtain higher bonding strength. Combined treatment can be more effective when surface the surfaces are kept clean and homogeneous.

• Restorative Dentistry and Endodontics
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• 제42권3호
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• pp.188-199
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• 2017

Objectives: This in vitro study evaluated the effect of dentin biomodifiers on the immediate and long-term bond strengths of a simplified etch and rinse adhesive to dentin. Materials and Methods: Flat coronal dentin surfaces were prepared in 120 extracted human molars. Teeth were randomly divided into 5 groups (n = 24) according to 5 different surface pre-treatments: No pre-treatment (control); 1M carbodiimide (EDC); 0.1% epigallocatechin-3-gallate (EGCG); 2% minocycline (MI); 10% sodium ascorbate (SA). After surface pre-treatment, adhesive (Adper Single Bond 2 [SB], 3M ESPE) was applied. Composite was applied into transparent plastic tubes (2.5 mm in diameter), which was placed over the bonded dentin surface. From each group, 10 samples were subjected to shear bond strength (SBS) evaluation at 24 hours (immediate) and remaining 10 samples were tested after 6 months (delayed). Additionally, 4 samples per group were subjected to scanning electron microscopic analysis for observation of resin-dentin interface. The data were statistically analysed with Shaperio-Wilk W test, 2-way analysis of variance (ANOVA), and post hoc Tukey's test. Results: At 24 hours, SBS of all surface pre-treatment groups were comparable with the control group, with significant differences found between EDC and SA groups only (p = 0.009). After 6 months storage, EDC, EGCG, and MI pre-treatments preserved the resindentin bond strength with no significant fall. Conclusions: Dentin pre-treatment with all the dentin biomodifiers except SA resulted in significant preservation of resin-dentin bond over 6 months storage period, without negatively affecting the immediate bond strength of the etch and rinse adhesive tested.