• Restorative Dentistry and Endodontics
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• 제19권2호
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• pp.447-459
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• 1994

The purpose of this study is to evaluate of shear bond strength of light-curing composite resin to light-curing glass ionomer cement. Composite resin and glass ionomer cement have been widely used as an esthetic filling materials in dental clinics. To achieve better clinical results, sandwich technic was developed with conpensating for disadvantages of these two materials. Especially, light-curing glass ionomer cement provided greately improved bonding strength of teeth or composite resin, and then excellent clinical results can be acquired. In this study, 6 commercial light-curing glass ionomer cements(3 commercial restorative materials : Fuji II LC, Variglass VLC, Vitremer, and 3 commercial lining materials : Fuji Lining LC, Baseline VLC, Vitrebond) were devided two groups. According to manufacturer's appointment, no surface treatment was referred to N groups. Supposing. of clinical practice, surface grinding with water spray at 320 grit sand paper, 40 seconds etching with 37% phosphoric acid, 20 seconds washing, 20 seconds air drying was referred to N groups. Totally 12 experimental groups were devided, and all 120 specimens from 10 specimens of each groups were made. After light-curing composite resin was bonded to light-curing glass ionomer cement, shear bond strength was tested by Instron universal testing machine between glass ionomer cement and composit resin. The data were analyzed statistically by Student's t-test and ANOVA. The obtained results were as follows; 1. In light-curing glass ionomer cement, restorative materials showed higher shear bond strength to composite resin than lining materials(p<0.05). 2. Variglass VLC of restorative material group and Baseline VLC of lining material group have highest shear bond strength to composite resin(p<0.001). 3. In light-curing glass ionomer cement, surface grinding and acid etching reduced shear bond strength to composite resin(p<0.001)}. 4. VGN group 1s highest shear bond strength to composite resin, VBE group is lowest shear bond strength to composite resin(p<0.001).

• 대한화학회지
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• 제42권2호
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• pp.172-176
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• 1998

뱃치법을 이용하여 음이온 교환수지(Amberlite IRA 400, $Cl^-$형)에 Alizadin Red S(ARS)를 결합시킨 수지를 얻었다. 이 수지는 0.5M 이하의 무기산에서 안정하였으며 Fe(Ⅱ)이온의 흡착력이 다른 이온에 비해 컸다. Fe(Ⅱ)이온을 예비 농축할 수 있었으며 다른 이온으로부터 분리하는데는 용리액으로 pH4.5의 완충용액과 0.1M $HNO_{3}$용액이 사용되었다.

• Restorative Dentistry and Endodontics
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• 제24권1호
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• pp.147-155
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• 1999

The purpose of this study was to investigate the effect of phosphoric acid concentration on the movement of 2-hydroxyethylmethacrylate(HEMA) from bonding resin - resin composite combination through dentin in vitro. Freshly extracted human third molar teeth were divided into four groups each of 10 teeth. A closed chamber with 1 ml distilled water was attached to the CEJ of each tooth. An occlusal cavity of 4mm diameter & remaining dentin thickness of 1.0-1.5mm was prepared in each tooth. Dentin was treated with 10% phosphoric acid gel for 15 seconds. 32% phosphoric acid gel for 15 seconds, or with 35% phosphoric acid gel for 15 seconds. A control group not treated with acid gel was also prepared. The cavities were rinsed, dried and then treated with the HEMA-containing All-Bond 2 primer & bonding resin which was light-cured for 10 seconds. The cavities were then restored with Z100 composite resin(shade:A3.5:3M Dent. Prod. USA) & light cured for 30 seconds. Water samples were retrieved from the chambers over a time course (4.32, 14.4, 43.2, 144 & 432 minutes ; 1, 3 & 10 days) and analyzed by high performance liquid chromatography. The results were as follows. 1. HEMA was detected in the pulp chambers of all teeth from 4.32 minutes after resin placement The highest rate of release was in the first sample period (0-4.32 min) & rate of release declined exponentially thereafter. 2. No significant differences were found for mean release rate for HEMA over a time course among the four groups (p>0.05). 3. The diffusion rate was significantly (p<0.05) less for 10% phosphoric acid gel than 32% phosphoric acid gel at the second sample period(4.32-14.4 min). 4. No significant differences were found for cumulative HEMA diffusion among the four groups at 10 days(p>0.05) and mean total(cumulative) release at 10 days for all groups was in the 9 - 16 nmol range. 5. The cumulative release was significantly (p<0.05) less for 10% phosphoric acid gel than 32% phophoric acid gel at the third(14.4-43.2 min) & fourth(43.2-144 min) sample period.

• 한국전기전자재료학회논문지
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• 제18권6호
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• pp.499-505
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• 2005

We compared the effects of a representative aromatic acid amplifier, 2-hydroxy-2'-tosylory biphenyl, doped in poly(tort-butyl methacrylate) (PTBMA), poly (tetrahydropyranylmethacrylate) (pTHPMh) or poly[tert-butoxycarbonyloxystyrene) (pTBOCST) resin film as acid labile polymer in view of thermal stability and photosensitivity enhancement. The acid amplifier was stable up to 60 min in pTBMA and pTBOCST film and up to 10 min in pTHPMA film at $120^{\circ}C$. pTBMA and pTHPMA film doped with the acid amplifier showed 9 times and 3 times higher photosensitivity, respectively. But pTBOCST film showed a negligible photosensitivity enhancement. Photosensitivity enhancement and thermal stability of the acid amplifier were found to be affected by the resin.

• 대한소아치과학회지
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• 제45권2호
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• pp.179-184
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• 2018

본 연구는 유전치 순면의 백색병소에 대한 표면처리 방법에 따른 레진 침투법의 침투 깊이를 공초점 레이저 주사 현미경으로 조사함으로써, 유치의 초기 우식병소에 대한 레진침투법 적용 과정에서, 염산 이외의 대안적 표면처리 방법을 모색할 목적으로 시도되었다. 15% 염산 단독으로 2분간 산부식 한 대조군과 35% 인산 단독으로 2분간 산부식을 시행한 I군 간의 유의한 차이는 보이지 않았다. 하지만 이 두 그룹과 인산 산부식 전 치면세마용 퍼미스 또는 연마용 metal strip으로 표면 전처리를 한 그룹 간에는 레진 침투율에서 유의한 차이를 확인하였다(p < .05). 유전치 초기 우식 병소에 레진 침투법을 시행할 때에는 35% 인산 단독 산부식만으로도 15% 염산을 이용한 산부식에 비견할 만한 침투 효과를 보이는 것을 확인하였다. 또한 레진의 침투 효과를 높이기 위해서는 산부식 전 병소 표면에 기계적 마모술을 적용하는 것이 효과적인 방법이 될 수 있음을 보여주었다. 이러한 방법은 소아치과 영역에서 레진침투법을 사용하기에 비교적 안전하고 쉽게 활용할 수 있는 표면처리 방법이라 볼 수 있다.

• 한국산림과학회지
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• 제96권1호
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• pp.54-57
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• 2007

요소수지접착제를 합판제조용 접착제와 유사하게 실험실에서 합성하고, 합성한 요소수지접착제를 증량제, 충전제, 산경화촉매제와 혼합하였다. 요소수지접착제 혼합물의 고형분량은 56.1%이고, 물은 43.9%였다. 국산재와 요소수지접착제 혼합물로 5종류의 Com-Ply를 제조하고, KS F 3101 보통합판의 인장 전단 접착력 시험 및 KS F 3104 파티클보드의 휨파괴계수 시험을 수행했다. 성능 평가된 결과는 제조된 5종류의 Com-Ply에서 모두 적합한 결과를 보여줬다. 이런 결과는 본 연구에서 사용된 요소수지접착제 혼합물이 국산재 Com-Ply제조에 적합하다는 것이다.

• The Journal of Advanced Prosthodontics
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• 제9권2호
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• pp.77-84
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• 2017

PURPOSE. The aim of this study was to compare the surface roughness of zirconia when using Zircos E etching system (ZSAT), applying a nitric acid-hydrofluoric acid compound as a pretreatment agent, and also to compare the shear bonding strength according to different resin cements. MATERIALS AND METHODS. ZSAT, air abrasion, and tribochemical silicacoating were applied on prepared 120 zirconia specimens (10 mm in diameter, 7 mm in height) using CAD/CAM. Each 12 specimens with 4 different resin cements (Panavia F 2.0, Rely X Unicem, Superbond C&B, and Hot bond) were applied to test interfacial bond strength. The statistical analysis was performed using SAS 9.1 (SAS Institute Inc., Cary, NC, USA). The results are as follows: after application of the ZSAT on the zirconia specimens, surface roughness value after 2-hour etching was higher than those after 1- and 3-hour etching on SEM images. RESULTS. For Superbond C&B and Rely X Unicem, the specimens treated with ZSAT showed higher shear bond strength values than those treated with air abrasion and tribochemical silicacoating system. Regarding the failure mode of interface over cement and zirconia surface, Rely X Unicem and Hot bond showed cohesive failures and Panavia F 2.0 and Superbond C&B showed mixed failures. CONCLUSION. Zircos E etching system in zirconia restoration could increase its shear bond strength. However, its long term success rate and clinical application should be further evaluated.

• 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.

• 한국가구학회지
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• 제10권1호
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• pp.43-49
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• 1999

The pH and buffering potential for water extract of seven hardwoods and three softwoods were determined. The pH values ranged from 3.81 to 5.51 for hardwoods and 4.08 to 5.49 for softwoods. The gelation time for a urea-formaldehyde resin for each woods was determined and found to be a range of one minute thirty seven seconds to two minutes thirty nine seconds. Results shows that gelation time of a urea-formaldehyde resin was directly correlated to the pH and inversely correlated with acid buffering potential for seven hardwoods and three softwoods aqueous extracts

• KSBB Journal
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• 제5권4호
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• pp.397-402
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• 1990

Hydrolysis of inulin was investigated employing various commercially available resin catalysts for the production of high grade fructose syrup. The particle size and porosity of the resin significantly affected the distribution of the products, indicating that the intraparticle diffusion of reactants controls thc selectivity as well as the reaction rate. To confirm the effect of the intraparticle diffusion, two different types of resin catalysts were prepared: the one having sulfonic acid group distributed uniformly throughout genular microparticles (A-type) and the other having sulfonic acid group located mainly at the exterior surface of genular microparticles (E-type). The results were found that the reaction rate and the selectivity of the E-type catalyst were higher than those of the A-type catalyst.