• 한국가구학회지
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• 제14권2호
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• pp.21-29
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• 2003

This study was carried out to investigate characteristics of plywood overlaid with softwood veneers densified by resin impregnation and compression. The resin impregnability of Korean pine veneer under atmospheric pressure soaking was greater than that of larch, and impregnability of melamine resin was slightly greater than phenolic resin. It was suggested that resin impregnation ratio was affected by density and thickness of veneer. The largest melamine resin impregnation ratio of 50.7% was obtained with 1.26mm thick Korean pine veneer, and the lowest phenolic resin impregnation ratio of 11.7% with 3.41mm thick larch veneer. Therefore, it was suggested that the vacuum-pres sure-soak treatment is required at thick larch veneer. In densifying resin-impregnated veneers, densification ratio from 13.4 to 31.2% was obtained by high pressure from 15.6 to $20.8kgf/cm^2$. Impregnation of melamine resin also showed relatively greater at densification than that of phenolic resin. So it showed the degree of densification of about 20% or greater. It was seemed that adhesive bonding strength of plywood(base panel) which was directly pressed and overlaid with resin-impregnated veneer was affected by resin tackiness after resin impregnation followed by semi-drying. In laboratory scale, melamine resin impregnation was more favorable for the development of adhesive bonding strength owing to moisture control.

• Restorative Dentistry and Endodontics
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• 제26권4호
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• pp.316-325
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• 2001

The purpose of this study was to evaluate the effect of adhesive curing timing on the direction of polymerization shrinkage of light-curing composite resin. In this study, the curing times of adhesive and composite resin were measured by differential scanning calorimeter(DSC). 28 extracted human molars were embedded in clear resin and box-type cavities were prepared. Based on DSC data, the experimental teeth were divided into 4 groups. Group 1: no bond; Group 2: late curing; Group 3: Intermediate curing; Group 4: Early curing. After treating with adhesive, the buccal cavities were filled with Z-100 hybrid composite resin and the lingual ones were filled with AEliteflo flowable composite resin. The depressions at the surface were measured by surface profilometer, then the specimens were embedded in clear resin and sectioned. Impressions were obtained and used to get epoxy resin replicas. The epoxy replicas were gold-coated and observed under SEM. Average Maximum Gap(AMG), Gap Proportion(GP), Average Marginal Index(AMI) were used to compare the shrinkage gap of each group. The results were statistically analyzed using the Kruskal-Wallis One Way ANOVA, Student-Newman-Keuls method. The results of this study were as follows. 1. Average Maximum Gap, Gap Proportion, Average Marginal Index and depression at the surface or Z-100 hybride composite resin were smaller than those of AEliteflo flowable composite resin(P<0.05). 2. When the bonding between composite resin and tooth structure was strong, the shrinkage gap was small, and depression at the surface was deep(P<0.05). 3. In the well-bonded group, light-curing composite resin shrank toward bonded cavity wall, not toward light source. The result suggested that the direction of polymerization shrinkage was affected by the quality of bonding in the dentin-resin interface. The strong was the bonding between composite resin and tooth structure, the smaller was the gap and the deeper was the depression at the surface. Then the flow to compensate the polymerization shrinkage proceeded from surface to bonded cavity wall.

• 대한치과보철학회지
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• 제45권2호
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• pp.159-168
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• 2007

Statement of problem: Literature showed different results on the durability of bonded ceramic restoration. Purpose: The purpose of this article is to review the effect of surface treatment of ceramics in resin-ceramic bond to get predictable results. Material and method: PubMed data base was utilized to search the articles which were written in English and published in 1986 and 2006. Some electronic published articles which are forthcoming to publish in paper were also included for this review. This review article focused on the effect of acid etching and silane application on the silica based ceramics. The durability of resin-ceramic bonding, the methodology for bond strength test and resin bonding to alumina or zirconia based ceramics were compared in brief at the end of the review. Results and Conclusion: the effect of silane application can be influenced by the contaminations of saliva or solutions. Micromechanical retention by acid etching as well as silane application plays an important role in initial and durable bond strength between resin and ceramic. The use of phosphate modified resin cement following tribochemical silica coating and silane application produced best bond strength for alumina or zirconia based ceramics.

• Journal of the Korean Wood Science and Technology
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• 제39권2호
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• pp.156-162
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• 2011

To evaluate the bonding performance of reinforced glulam, the textile type of glass fiber and aramid fiber, and the sheet type of glass fiber reinforced plastic (GFRP) and carbon fiber reinforced plastic (CFRP) were used as reinforcements. The reinforced glulam was manufactured by inserting reinforcement between the outmost and middle lamination of 5ply glulam. The types of adhesives used in this study were polyvinyl acetate resins (MPU500H, and MPU600H), polyurethane resin and resorcinol resin. The block shear strengths of the textile type in glass fiber reinforced glulam using MPU500H and resorcinol resin were higher than 7.1 N/$mm^2$, and these glulams passed the wood failure requirement of Korean standards (KS). In case of the sheet types, GFRP reinforced glulams using MPU500H, polyurethane resin and resorcinol resin, and CFRP reinforced glulams using MPU500H and polyurethane resin passed the requirement of KS. The textile type of glass fiber reinforced glulam using resorcinol resin after water and boiling water soaking passed the delamination requirement of KS. The only GFRP reinforced glulam using MPU500H after water soaking passed the delamination requirement of KS. We conclude that the bonding properties of adhesive according to reinforcements are one of the prime factors to determine the bonding performance of the reinforced glulam.

• Restorative Dentistry and Endodontics
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• 제32권5호
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• pp.426-436
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• 2007

본 연구에서는 접착레진의 부가적인 도포가 레진 시멘트의 결합강도에 미치는 영향을 연구하였다. One-Step Plus와 Choice, Single Bond와 Rely X ARC, One-Up Bond F와 Bistite II DC를 사용하였고 접착레진으로 D/E Bonding resin과 Pre-Bond Resin을 선택하였다. 적용 및 광중합 유무에 따라 12개의 군을 설정하였다. 제 3대구치의 건전한 상아질 면에 간접 복합레진 수복물을 제작하여 접착을 시행하고$1\;{\times}\;1\;mm^2$의 시편을 만들어 미세인장강도를 측정하였다. 또한 투과전자현미경으로 접착계면을 관찰하였다. 그리하여 다음과 같은 결론을 얻을 수 있었다. 1. Single Bond와 Rely X ARC, 그리고 One-Step Plus와 Choice를 조합하고 광중합을 시행한 군에서, 접착 레진을 부가적으로 도포할 경우 미세인장강도가 증가하였다. 2. One-Up Bond F와 Bistite II DC를 조합한 군에서 접착레진의 부가적인 도포에 의한 미세인장강도의 차이는 나타나지 않았다. 3. 광중합을 시행한 군들 중, One-Step Plus와 Choice를 조합한 군이 다른 군보다 높은 미세인장결합강도를 보였다. 4. 자가중합만을 시행한 군간에는 접착레진의 부가적인 도포에 의한 차이가 나타나지 않았다. 투과전자현미경 관찰을 시행하여 광중합을 시행하고 접착레진을 부가적으로 도포한 실험군에서 미세누출이 감소하고 접착층의 두께가 증가한 것을 확인할 수 있었다. 본 연구결과 완전산부식 상아질 접착제와 이중중합 레진 시멘트를 사용할 경우 부가적인 접착레진의 도포가 임상적으로 유용할 수 있다는 사실을 확인할 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제43권5호
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• pp.682-690
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• 2015

The bonding performance of two types of wood adhesives, namely phenol-resorcinol-formaldehyde (PRF) resin and melamine-urea-formaldehyde (MUF) resin for glued laminated timber manufactured by high frequency (HF) heating was evaluated. The HF heating system consists of HF oscillator with dielectric heating system for curing adhesives, and hydraulic press system for clamping glued laminated timber. The designed frequency and output power of the HF system was as 5 MHz and 60 kW, respectively. To verify dielectric heating mechanism under HF oscillation, the heat loss factors of laminae and adhesives were measured. The results show that it is possible to selectively heat adhesives for their curing due to the remarkably higher loss factor of the adhesives than those of wood laminae. The temperature of adhesive in the bonding line reached up to the set temperature within a few seconds by high frequency oscillating, which advanced the curing of adhesive afterwards. The bonding performance, such as shear strength of bonding line, water soaking delamination, and boiling water soaking delamination of PRF resin met the requirement of Korean Standard (KS), however the MUF resin did not meet the KS requirement of boiling water soaking delamination. These results indicate that the HF heating system is successful to manufacture glued laminated timbers with PRF resins to meet the bonding requirements.

• 대한치과보철학회지
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• 제47권2호
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• pp.174-181
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• 2009

연구목적: 본 연구에서는 35% 과산화수소를 사용하는 전문가 미백 술식에서 레진 접착제의 접착력 회복을 위한 유예 기간을 비교하고자 한다. 연구 재료 및 방법:3M사의 Single Bond와 Z350을 이용하여 미백 직 후, 1일후, 2일후, 일주일 후의 시간 차이를 두고 상아질에 접착된 복합 레진의 전단 결합 강도를 측정하여 다음과 같은 결과를 얻었다. 결과: 미백 처리 직 후의 상아질 전단 결합 강도는 다른 군에 비해 유의하게 낮았으며(P<.05), 미백 처리 전에 비해 약 78%의 결합력 감소를 보였다. 미백 처리 1일 후의 상아질 결합 강도는 미백 직 후 감소된 결합력의 51%에 이르는 회복을 보였으며, 2일 경과한 시편에서는 감소된 결합력의 63%가 회복되었다. 두 군은 미백 직 후에 비해 유의하게 큰 회복력을 보였으나, 두 군 간에는 유의한 차이가 없었다(P>.05). 미백 처리 후 결합력의 회복은 초기 24시간 이내에 급격히 일어나며 그 이후에는 서서히 일어나는 것으로 사료된다. 미백 일주일 후의 시편은 미백 처리 전에 비해97%에 이르는 결합력을 보이며 두 군 간에는 유의한 차이가 없었다(P>.05). 결론: 그러므로35% 과산화수소를 적용하는 전문가 미백 술식에서는 1주일간의 유예기간을 두고 복합 레진 접착술을 시행하는 것이 적절할 것으로 사료된다.

• Restorative Dentistry and Endodontics
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• 제25권2호
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• pp.243-253
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• 2000

The purpose of this in vitro study was to evaluate dentin bonding by two different dentin bonding systems(DBS) using acetone based primer or adhesive [All Bond 2(AB2), One Step(OS)] when they were applied by wet or dry bonding technique. Morphology of resin-dentin interface and hybrid layer thickness(HLT) were investigated using Confocal Laser Scanning Microscope(CLSM) and compared to shear bond strength(SBS). 72 extracted sound human molars were randomly divided into 4 groups of 18 teeth each - Group 1.(AW); AB2 by wet bonding. Group 2(AD); AB2 by dry bonding. Group 3.(OW); OS by wet bonding, Group 4.(OD); OS by dry bonding. In 6 teeth of each group, notch-shaped class V cavities(depth 2mm) were prepared on buccal and lingual surface at the cementoenamel juction(12 cavities per group). To obtain color contrast in CLSM observation, bonding resins of each DBS were mixed with rhodamine B and primer of AB2 was mixed with sodium fluorescein. Prepared teeth of each group were treated with AB2, OS, respectively according to the manufacturer's instructions except for dentin surface moisture treatment after acid etching. In group 1 and 3, after acid etching, excess water was removed with wet tissue(Kimwipes), leaving consistently shiny, visibly hydrated dentin surface. In group 2 and 4, dentin surface was dried for 10 seconds at 1 inch distance. The treated teeth were then packed with composite resin(${\AE}$litefil) and light-cured. 12 microscopic samples($60{\sim}80{\mu}m$ thickness) of each group were obtained after longitudinal section and grinding(Exakt cutting and grinding system). Morphological investigation of resin-dentin interface and HLT measurement using CLSM were done. For measurement of SBS, remaining 12 teeth of each group were flattened occlusally to remove all enamel and grinded to 500 grit SiC(Pedemet Specimen Preparation Equipment). After applying DBS on the exposed dentin surface, composite resin was applied in the shape of cylinder, which has 5mm diameter, 1.5mm thickness, and light cured. SBS was measured using Instron with a crosshead speed of 0.5mm/min. It was concluded as follows, 1. HLT of AW(mean: $2.59{\mu}m$) was thicker than any other group, and followed by AD, OW, OD in descending order(mean; 2.37, 2.28, $1.92{\mu}m$). Only OD had statistically significant differences(p<0.05) to AW and AD. 2. There were intimate contact of resin and dentin at the interface in wet bonding groups, but gaps or irregular interfaces were observed in dry bonding groups. 3. The length, diameter, density of resin tags were various even in the same group without significant differences between groups and lots of adhesive lateral branches were observed. 4. There were no statistically significant difference of SBS between AB2 and OS, but SBS of wet bonding groups were significantly higher(p<0.05) than dry bonding groups. 5. There were no consistent relationships between HLT and SBS.

• Restorative Dentistry and Endodontics
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• 제34권5호
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• pp.397-405
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• 2009

이 연구의 목적은 자가 중합복합 레진과 두 단계 산 부식 접착제의 친화성에 대한 중간 접착제와흐름성 레진의 효과를 미세 인장 결합 강도를 통해 비교하는 것이었다. 20개의 발거된 대구치를 사용해 접착제와 부가적인 적용(활성제, 중간 접착제, 흐름성 레진)에 따라 XP bond 그룹 (XA, XB, XF 그룹), Prime & Bond NT 그룹 (NA, NB, NF 그룹), Optibond solo plus 그룹 (OA, OB OX 그룹)으로 나누었다. 접착제 적용 후 활성제, 중간 접착제, 흐름성 레진을 각각 적용하고 상부에 자가 중합 레진을 축성하였다. 24시간 동안 실온의 증류수에 보관 후 각 그룹당 10개의 시편을 준비하였다. 모든 시편의 미세인장 결합 강도를 측정하여 다음과 같은 결과를 얻었다. 1. 모든 그룹에서 중간 접착제와 흐름성 레진의 적용은 활성제 적용보다 더 높은 결합 강도를 보였다. 2. 선택된 방법에 관계없이, Optibond solo plus 그룹은 가장 낮은 미세인장 결합강도를 보였다. 3. 파절 양상은 대부분 접착성 파절을 보였고 일부 레진 내에서 응집성 파절을 보였다. 이번 연구의 결과로부터, 중간 접착제와 흐름성 레진의 적용이 낮은 pH를 가지는 두 단계 산 부식 접착제와 자가 중합복합 레진의 상아질 접착에 더 효과적이라 예상된다.

• Restorative Dentistry and Endodontics
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• 제18권2호
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• pp.423-430
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• 1993

The purpose of this study was to investigate the effect of ferric and ferric ions contained in phosphoric acid solution as a pretreatment solution on bonding of MMA/TBBO resin to dentin. Each of 1 % and 3 % ferric chloride. cupric chloride. cupric sulfate. and cupric nitrate was mixed into 10% phosphoric acid solution and pretreated dentin surface of bovine anterior teeth for 30 seconds followed- by water rinse and dry. Tensile bond strength was determined after bonding of pretreated dentin with MMA/TBBO resin by use of brush-on ;technique and storing for 24 hours in 3it distilled water. The amount of cupric ions adsorbed on pretreated dentin surface was detected by Wave-Dispersion X-ray microanalyzer for different groups of each pretreatment solution containing cupric salts. The pretreatment with cupric ions contained in 10% phosphoric acid solution was effective to increase bonding strength of MMA/TBBO resin to dentin but not in case of ferric ions. The pretreatment with 3 % cupric chloride and cupric nitrate both enhanced significant increase in bonding strength compared to the control group of 10% phosphoric acid solution(p<0.05). Cupric ions measured in pretreated dentin surface was higher in 3 % cupric chloride group than in 1% cupric chloride group, but couldn't find distinct relationship from the results of this experiment between the amount of adsorbed cupric ions according to the kind of cupric salts and the bonding strength value.