• Restorative Dentistry and Endodontics
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• v.28 no.4
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• pp.314-325
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• 2003

이 연구의 목적은 수종 상아질 접착 시스템과 복합 레진 및 resin-modified glass ionomer를 상아질 표면에 접착하여 재료 및 상아질내 위치에 따른 미세전단결합강도를 측정, 비교하는 것이다. 상아질 접착 시스템으로는, 3-step인 Scotchbond Multi-Purpose Plus, 2-step인 Single Bond와 자가 부식형 시스템인 Clearfil SE Bond를, 1-step인 Prompt L-Pop을 사용하였다. 이와 함께 hybrid type의 복합 레진인 Clearfil AP-X와 2250을 사용하였으며 resin-modified glass ionomer로는 Fuji II LC를 사용하였다. 상악 소구치를 치아의 근원심 중앙부를 절단하여 상아질면을 노출시켰다. 5개 실험군으로 분류하고 상아질면을 위치에 따라 치관부의 occlusal $\frac{1}{3}$, middle $\frac{1}{3}$, cervical $\frac{1}{3}$과 치근부로 구분지어 시편을 부착하였다. 미세전단결합강도측정는 Universal testing machine(EZ-test; Shimadzu, Japan)에서 측정하였다. Occlusal 1/3부위에서는 SE가 가장 높은 값을, SM과 SB간에는 유의차가 없었으며, PL, GI순으로, Middle 1/3부위에서는 $SM{\;}{\geq}{\;}SE{\;}{\geq}{\;}SB{\;}{\geq}{\;}PL{\;}{\geq}{\;}GI$순으로, cervical 1/3부위에서는 SM, SE, SB간에 유의차가 없었다. Root dentin에서는 SM이 가장 높은 값을 보였으며 SE, PL, GI간에 유의차가 없었다. SE만이 치관부 상아질에 비해 치근부에서 유의할만한 결합강도의 감소를 나타냈다(p<0.05). GI는 치관부 상아질에서는 다른 군에 비해 유의성 있게 낮은 결합강도를 보였으나 치근부에서는 SE, PL과 유의차가 없었다.

• The korean journal of orthodontics
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• v.34 no.4 s.105
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• pp.325-332
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• 2004

A self-etching primer that combines the etchant and primer in one chemical compound saves time and should be mote cost-effective to the clinician and patient. The purpose of this study was to evaluate the clinical effectiveness of a self-etching primer by measuring shear bond strengths according to various conditions and observing adhesive failure patterns. For this Investigation, 120 upper and lower premolars extracted for orthodontic purposes were used and randomly divided into six groups of twenty teeth each. Human premolars were embedded in a metal cylinder with orthodontic resin. Metal brackets and ceramic brackets were bonded with XT primer and self-etching primer by means of XT adhesive. Upon curing, plasma arc light and visible light were used. After bonding, the shear bond strength was tested by Instron universal testing machine, and the amount of residual adhesive that remained on the tooth after debonding was measured by stereoscope and assessed with an adhesive remnant index. The results were as fellows: 1. When brackets were bonded, if other conditions remained the same, there was no significant difference in shear bond strength due to the type of primer - either self-etching primer or XT primer. 2. When metal brackets were bonded, there was no significant difference in shear bond strength according to the source of light - plasma arc light or visible light - and type of primer. 3. There was a very significant difference in shear bond strength according to the type of brackets - metal or ceramic brackets. The shear bond strength of ceramic brackets was stronger than metal brackets. 4. When the adhesive failure patterns of metal brackets bonded with self-etching primer were observed by using the adhesive remnant index, the bond failure of the metal bracket occurred more frequently at the bracket-adhesive. The failure of the ceramic bracket, however, occurred more frequently at the enamel-adhesive interface. The adhesive failure patterns of metal brackets bonded with XT primer observed the same patterns. The above results suggest that self-etching primer can be clinically useful for bonding the brackets without fear of a decrease in shear bond strength.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.4
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• pp.209-216
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• 2021

Purpose: The purpose of this study is to compare the shear bond strength of resin cement for orthodontic brackets without applying an adhesive primer, to the case of applying an adhesive primer. Materials and Methods: The specimens were divided into three experimental groups, Transbond XT, GC Ortho Connect and Orthomite LC, and the enamel surface was divided into two sections, one with 37% phosphoric acid and the other with 37% phosphoric acid and an adhesive primer or universal adhesive. Each of three types of cement was applied to orthodontic bracket, and after bonding, the shear bond strength was measured. Results: Transbond XT and Orthomite LC significantly increased shear bond strength when orthodontic brackets were bonded after applying an adhesive primer and universal adhesive, respectively. Conclusion: It is expected that application of an adhesive primer or universal adhesive after acid etching will improve shear bond strength of orthodontic brackets in Transbond XT and Orthomite LC.

• Restorative Dentistry and Endodontics
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• v.29 no.1
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• pp.30-35
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• 2004

치아 미백술은 치아의 심미성을 향상시키는 가장 보존적인 방법의 하나로 인식되어져 왔으며 최근의 심미치과에 대한 관심의 증가와 함께 그 빈도가 급격히 증가하고 있는 술식의 하나이다. 일반적으로 치아 미백술 후 바로 접착수복을 할 경우 결합력이 감소하는 것으로 알려져 있으며 이를 해소하기 위해 일정시간 경과 후 접착수복 술식을 시행할 것을 권장 하고 있다. 자가산부식형 (self-etching primer system) 접착제는 기존의 접착제와 다른 성분으로 인해 치아미백제에 의한 영향에 대해 잘 알려져 있지 않은 상태이다. 이에 본 실험에서는 미백술을 시행한 법랑질 상에서 서로 다른 세 가지의 접착 시스템을 이용하여 미백술 후의 지연 시간이 결합력에 미치는 영향을 비교하고자 하였다. 발거한 대구치 68개를 물기가 있는 상태에서 근원심으로 절단하고 치관부를 자가중합 레진에 식립하여 시편을 제작하였다. 세 가지 접착제로 $One-step^{\circledR}$, Clearfil SE Bond $primer^{\circledR}$, One-up Bond $F^{\circledR}$를 이용하였다. 각 접착제를 미백을 시행하지 않는 대조군과 미백 시행 후 바로 접착한 즉시 접착군, 그리고 2주간 생리식염수에 보관한 후에 접착한 지연군으로 나누어 총 9개의 실험군으로 나누었다. 접착제를 처리한 면에 Clearfil $AP-X^{\circledR}$ 복합레진을 2mm충전하고, 40초간 광중합을 시행하였다. 24시간 후 전단접착강도를 측정하였으며, 그 결과는 다음과 같이 나타났다. $One-step^{\circledR}$의 경우, 즉시 접착군에서 지연 접착군보다 유의성 있게 낮은 접착강도를 나타내었다. Clearfil SE $Bond^{\circledR}$의 경우, 즉시 접착군과 미백을 시행하지 않은 군간에는 접착 강도에 유의한 차가 없었으나,지연접착군에서는 낮은 강도를 나타내었다. One-Up Bond F$^{\circledR}$의 경우, 즉시 접착군에서 유의성 있게 낮은 전단접착강도를 나타내었고, 전반적인 접착 강도가 다른 두 접착제에 비해서 유의성 있게 낮은 값을 보였다. $One-step^{\circledR}$을 사용할 경우 지연접착을 하는 것이 추천되며, Clearfil SE Bond$^{\circledR}$의 경우에는 즉시 접착을 시행하더라도 영향을 적게 받는 것으로 나타났으며, One-Up Bond $F^{\circledR}$의 경우 미백술 후 접착수복 과정에 사용에 제한이 있는 것으로 나타났다.

• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.38-42
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• 2008

Effect of polyol structure and NCO index on adhesion of PU adhesive at room ($25^{\circ}C$) and extremely low temperature ($-190^{\circ}C$) was investigated. At room temperature adhesive strength of PU adhesive tends to decrease as molecular weight of polyol increases, however, the strength at $-190^{\circ}C$ shows opposite tendency. Adhesive strength of the PU turned out to be directly proportional to the amount of MDI. PU containing aliphatic polyol was higher in shear strength at $-190^{\circ}C$ and the strength of PU with aromatic polyol was higher at room temperature.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.1
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• pp.27-32
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• 2013

Purpose: The aims of this study were to evaluate the effect of a resin coating on the shear bond strength of indirect composite restoration bonded to dentin with a self adhesive resin cement and to compare the shear bond strength with that of a conventional resin cement. Materials and methods: The occlusal enamels of thirty six extracted noncarious human molars were removed until the dentin flat surfaces of the teeth were exposed. Then, they were divided into 3 groups. The dentin surfaces of group 1 and 3 were left without any conditioning, while the dentin surfaces of group 2 were resin-coated with Clearfil SE bond and a flowable resin composite, Metafil Flo. After all specimens were temporized for 24 hours, indirect composite resin blocks fabricated by Tescera were bonded to dentins by Unicem for group 1 and 2, and by Panavia F for group 3. After 48 hours of water storage, shear bond strengths were measured. The data was analyzed with one-way analysis of variance and multiple comparison test (Tukey method). Results: The shear bond strengths of Unicem applied to resin coated dentin surfaces were significantly higher than those of Unicem and Panavia F used to uncoated dentin surfaces (P<.0001). Conclusion: Application of a resin coating to the dentin surface significantly improved the shear bonding strength of a self adhesive resin cement in indirect restoration.

• The korean journal of orthodontics
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• v.35 no.6 s.113
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• pp.443-450
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• 2005

This study was performed to compare the shear bond strength of orthodontic adhesive to amalgam according to different light sources (halogen-based light and light emitting diode (LED)) and amalgam surface treatments. Ninety extracted human premolars were randomly divided into 6 groups (4 experimental and 2 control groups) of 15 by light sources and surface treatments. Orthodontic brackets were bonded and shear bond strength was measured with an Instron universal testing machine. The findings were as follows: The bond strength of adhesive to amalgam surface was 3-5.5 MPa which was lower than that of acid-etched enamel (19 MPa) control. In the sandblasted amalgam surface, the shear bond strength of the halogen light group was higher than that of the LED group (p < 0.05) but. in the non-treated amalgam surface. there was no significant difference in the shear bond strength according to the light sources (p> 0.05). Within the same light source. sandblasting had no significant effect on the shear bond strength of the adhesive bonded to amalgam surface (p > 0.05). There was no significant difference in shear bond strength according to the light sources in acid-etched enamel control groups. This results suggest that there can be a limit in using light curing adhesives when brackets are bonded to an amalgam surface. Additional clinical studies are necessary before routine use of halogen light and LED light curing units can be recommended in bonding brackets to an amalgam surface.

• Journal of Adhesion and Interface
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• v.21 no.2
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• pp.65-70
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• 2020

Epoxy adhesive was mainly used to combine different composite materials. Epoxy adhesive was a typical thermosetting resin that can be bonded by changing from a linear structure to a three-dimensional network structure by curing reaction of epoxy and hardener. The curing conditions of epoxy adhesive were different with different types of hardener such as mixing ratio, curing time, and temperature. These curing conditions affected to the adhesive property of epoxy adhesive. In industry, it was difficult to proceed the applying epoxy adhesive and combining two parts immediately. The adhesive property decreased by humidity and pre-curing of epoxy adhesive in waiting time between two processes. In this paper, the glass fiber reinforced composite (GFRC) was combined with epoxy adhesive and adhesion property between epoxy adhesive and GFRCs was evaluated using single lap shear test. The different waiting times and humidity conditions were applied to epoxy adhesive in room temperature and adhesive property decreased as the waiting time increased. In small amount of humidity, the adhesive property increased because a small amount of moisture in the surroundings accelerated the curing reaction. In certain amount of humidity, however, the adhesion property decreased.

• The korean journal of orthodontics
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• v.31 no.3 s.86
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• pp.381-391
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• 2001

In orthodontic patients, frequently, amalgam restorations are present on the buccal surface of molars. The ability to successfully bond orthodontic brackets and buccal tubes to amalgam restorations would therefore be of clinical value. But the bond strength to total amalgam surface is probably not critical in most instances. Because there is usually a considerable amount of sound enamel surrounding a buccal amalgam filling. The purpose of this study was to evaluate the bond strengths of orthodontic brackets according to surface treatments and size of amalgam restorations. Eighty tooth specimen were assigned to four groups according to amalgam size-1.5mm, 2.0mm, 2.5mm, 3.0mm diameter-and then divided into two groups : one half was sandblasting group the other half was no sandblasting group. After Bracket bonding, shear bond strength for each specimen was determined and bond failure patterns was evaluated. 1. Shear bond strength of amalgam size 1.5mm group was significantly higher than that of the other groups. (p<0.05) 2. There was no significant difference in the bond strength produced by sandblasting. (p<0.05) 3. Shear bond strength of G and H group of which amalgam restoration ratio to the bracket base sizes were $61\%$ were significantly decreased $50-60\% level of that of control group. (p<0.05) 4. There was positive correlation between sandblasting and mARI. (p<0.05) The results of the present study indicate that it may be feasible to bond orthodontic bracket clinically successfully to amalgam restoration with conventional orthodontic resin when its size is less than $50\%$ of that of bracket base.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.1
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• pp.25-32
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• 2016

The purpose of this study is to evaluate the performance on the compressive bonding shear strength of ultra-high strength steel fiber reinforced cementitous composites(UHSCC). As a result of compressive bonding shear strength through Direct shear test, It was found that the specimen($150{\times}150{\times}150mm$) of NC(Normal concrete) + NC showed similar compressive bonding shear strength at whole experimental level. On the other hand, the specimen of UHSCC + UHSCC showed decrease of compressive bonding shear strength from after 30 minutes of the retarded placement than 0 minute. As a result of analyzing failure mode of bonding interface, It was found that the specimen of NC + NC showed mixed failure at whole experimental level. In case of the specimen of UHSCC + UHSCC, it showed interface failure from the specimen that are 30 minutes, 60 minutes and 90 minutes of delay of concrete placing. As a result of analyzing XRD test in terms of the placement interface on the specimen of NC and UHSCC, relatively much amount of $SiO_2$ was detected from the specimen of UHSCC than that of NC. It is judged that the most of main components of coating film shown in the specimen of UHSCC is $SiO_2$. In conclusion, it is judged that UHSCC which is made from after 30 minutes of delay of concrete placing is unable to be used as structural member because of deterioration of bonding performance. From later study, it is judged that the improvement of bonding performance from the part of cold joint occurrence is necessary through the interface preparation method.