• 대한소아치과학회지
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• 제24권1호
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• pp.139-147
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• 1997

Argon laser used in this case report, is special in having two wavelength of 488, 514nm blue-green visible light spectrum. Blue light is used for composite resin polymerization and caries detection. Green light is used for soft tissue surgery and coagulation. Maximum absorption of this laser light occurs in red pigmentation such as hemoglobin. The argon laser may be well-suited for selective destruction of blood clots and hemangioma with minimal damage to adjacent tissues. Argon laser light penetrates tissue to the 1 mm depth, so its thermal intensity is lower than $CO_2$ laser light. Also, due to its short wavelength it can be focused in a small spot and even single gene can be excised by this laser and microscopy. After applicating argon laser to 4 patient for surgical procedure and to 1 patient for curing the composite resin, following results were obtained. 1. Improved visibility were gained due to hemostasis and no specific technique were needed according to easy recontouring of the tissue. 2. Ability to use by contact mode, tactile sense was superior but tissue dragability and accumulation of tissue on the tip needed sweeping motion. 3. Additive local anesthetic procedure was needed. 4. No suture and less curing time reduced chair time, this made argon laser available in pediatric dentistry.

• Restorative Dentistry and Endodontics
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• 제17권2호
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• pp.421-430
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• 1992

The purpose of this study was to evaluate the bond strength between the composite resin and light - cured glass ionomer cement base / liners treated by the several methods. The light - cured glass ionomer cement(Vitrebond / Cavalite) were injected into cavites prepared in acrylic plates. One hundred and twenty specimens were uniformly prepared and devided into 3 groups. For the first group, primer was not applied to glass ionomer cement. For the second group, no application of primer was undertaken and light - curing procedure to uncured glass ionomer cement surface which was covered by bonding agent was undertaken. After bonding composite resin to light - cured glass ionomer surface, the specimens, were stored in $37^{\circ}C$, 100% humidity for 1 hour. The following results were obtained : 1. The omission of application of a primer did not produce a significantly poorer bond strength. 2. Light - curing technique to uncured glass ionomer cement which was covered by bonding agent did not produce a significantly poorer bonding strength. 3. The bond strength of Cavalite to composite resin was significantly higher than that of Vitrebond. 4. There was no significant difference between two different types of composite materials(Silux-Plus / Herculite XR) when it was applied to bond to glass ionomer cement.

• Restorative Dentistry and Endodontics
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• 제32권3호
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• pp.248-259
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• 2007

이 실험의 목적은 광중합복합 레진을 자체 제작한 광조사 차단 장치를 이용하여 간헐적 광중합시켜 기존의 연속 중합법과 변연적합도를 비교함으로써 간헐적 광중합의 영향을 알아 보는 것이다. 이번 실험에 사용된 재료는 Pyramid (Bisco, Schaumburg, U.S.A)와 Heliomolar (Ivoclar Vivadent, Liechtenstein)이다. 발치된 상악 소구치에 class II MOD 와동 형성 후 위 두 재료를 bulk 충전하고 다음의 중합cycle에 따라 중합시켰다: 제1군- 연속 광중합 (60초간 계속 광조사); 제2군-2초 광조사, 1초 광차단 (90초 시행); 제3군- 1초 광조사 1초 광차단 (120초 시행); 제4군- 1초 광조사, 2초 광차단 (180초 시행). 저작재현장치 (R&B, Daejeon, Korea)로 720000회의 운동횟수, 분당 120의 회전속도, $5^{\circ}C$와 $55^{\circ}C$의 물을 교대로 치아에 6000회 주사하면서 5.0 kg의 하중을 치아에 적용하였고 실험 전후 변연적합도를 전체와 부위별 변연으로 나누어서 $\times200$배율의 광학 현미경으로 측정하였다. 부위별 변연은 교합면, 인접면, 치은면 등 세 부위로 나누어서 법랑질 변연을 측정하였다. 전체 변연적합도에서 각 군간, 재료간, 저작 운동 전후 차이를 보기 위해 three-way ANOVA와 Duncan's multiple range test를 시행하였고, 부위별 변연적합도에서는 각 군에서 부위별 차이와 각 부위에서 군간 차이를 보기 위해 각각 one-way ANOVA와 Duncan's multiple range test를 시행하였다 (95% 유의수준). 전체 변연적합도를 보면, 저작 운동 전에는 Pyramid의 경우 3, 4군이 1,2군에 비해, Heliomolar의 경우 3.4군이 1군에 비해 전체 변연적합도가 우수하였고, 저작 운동 후에는 Pyramid. Heliomolar모두 3군이 1군에 비해 전체 변연적합도가 우수하였다 (p < 0.05). 재료간 비교에서는 저작 운동 잔에는 2군에서 Heliomolar가 Pyramid보다 변연적합도가 우수하였고 (p < 0.05) 그 외의 군에서는 유의차가 없었으며, 저작 운동 후에는 모든 군에서 재료간 유의차가 없었다. 각 부위별 변연적합도를 비교하면, 저작 운동 전 Pyramid에서는 교합면 변연에서는 4군이 2군에 비해 높은 변연적합도를 보였고 (p < 0.05), 인접면과 치은면에서는 군 간 유의차를 보이지 않았다. Heliomolar에서는 교합면 변연에서 2, 4군이 1군에 비해 높은 변연적합도를 보였고 (p < 0.05), 인접면과 치은면에서는 군간 유의차를 보이지 않았다. 저작 운동 후 Pyramid에서는 교합면 변연에서는 3군이 1, 2군에 비해 높은 변연적합도를 보였고 (p < 0.05), 인접면과 치은면에서는 군간 유의차를 보이지 않았다. Heliomolar에서는 교합면에서 2, 3, 4군이 1군에 비해 변연적합도가 높았으며 (p < 0.05), 인접면과 치은면에서는 군간 유의차를 보이지 않았다 이번 연구를 통하여 복합레진을 간헐적 광중합시킴으로써 변연적합도가 향상될 수 있음을 알 수 있었다.

• 한국인쇄학회지
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• 제16권3호
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• pp.61-80
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• 1998

To investigate in influence of photosensitizer used with benzophenone(BP) in the curing rate and physical properties of UV curable hard coating on plastic, we prepared UV curable clear and pigmented coatings with DEA, DMA, NPM and TEA as photosensitizer, respectively. The curing rate calculated from the decrease of the absorbance of acrylic double bond measured by FT-IR spectroscopy increased s follows; DEA>DMA>NPM>TEA. this order could be explained by the reactivity of diethylamino group of DEA and the ease of formation of activated complex between BP and photosensitizer during the curing process. In UV curable pigmented coatings, the order of curing rate increased as follows; DEA>DMA>TEA>NPM. It was found that the curing rate of the pigmented coating can be increased by light scattering of TiO$_2$. The hardness of coating film cured by photosensitization of DEA and DMA is higher than other photosensitizers due to the crosslinking reaction of DEA and DMA radical bound to polymer backbone.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3787-3789
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• 2013

In this study, the silicone thermal curing degree of the silicone-encapsulated quantum dot light emission diode was measured using the various types of chemical ligands around quantum dot. It was confirmed that the trioctyl phosphin oxide (TOPO) ligand around the quantum dot was responsible for dispersion of the quantum dot in silicone encapsulant and decline of the thermal curing degree of the silicone encapsulant. Also, it was confirmed that the thermal curing degree of silicone encapsulants containing the steric acid (SA) and the dodecanoic acid (DA) ligands were higher than the one of TOPO ligand.

• Fibers and Polymers
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• 제2권4호
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• pp.184-189
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• 2001

Continuous photografting/crosslinking of polyethyleneglycol dimethacrylate oligomers onto cotton using a water-soluble benzophenone photoinitiator was investigated. Photografting increased with increasing irradiation dose, oligomer concentration and photoinitiator concentration. Maximum grafting efficiency of DM 400 and 600 were 83% and 79%, respectively. the photografting increased the wrinkle resistance of cotton implying surface crosslinking of cotton. bothsurface crosslinking and bulk crosslinking of cotton were accomplished via dual curing of a mixed formulation containing both a thermally curable component (BTCCA/SHP) and a UV-curable component. The wrinkle resistance of the crosslinked cotton was found to be higher when cured by thermal curing due to the facile post-polymerization of the UV active component. The presence of crosslinks in the dually crosslinked cotton was verified with FT-IR and thermogravimetric analysis.

• Imaging Science in Dentistry
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• 제42권2호
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• pp.89-93
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• 2012

Purpose : Clinicians commonly encounter cases in which it is difficult to determine whether adjacent radiopacities are normal or pathologic. The ideal radiopacity of composite resin is equal to or higher than that of the same thickness of aluminum. We aimed to investigate the possible effects of different curing times on the post-24-hour radiopacity of composite resins on digital radiographs. Materials and Methods : One mm thick samples of Filtek P60 and Clearfil resin composites were prepared and cured with three regimens of continuous 400 mW/$cm^2$ irradiance for 10, 20 and 30 seconds. Along with a 12-step aluminum step wedge, digital radiographs were captured and the radiopacities were transformed to the equivalent aluminum thicknesses. Data were compared by a general linear model and repeated-measures of ANOVA. Results : Overall, the calculated equivalent aluminum thicknesses of composite resins were increased significantly by doubling and tripling the curing times (F(2,8)=8.94, p=0.002). Notably, Bonferroni post-hoc tests confirmed that the radiopacity of the cured Filtek P60 was significantly higher at 30 seconds compared with 10 seconds (p=0.04). Although the higher radiopacity was observed by increasing the time, other comparisons showed no statistical significance (p>0.05). Conclusion : These results supported the hypothesis that the radiopacity of resin composites might be related to the duration of light curing. In addition to the current standards for radiopacity of digital images, defining a standard protocol for curing of dental materials should be considered, and it is suggested that they should be added to the current requirements for dental material.

• Restorative Dentistry and Endodontics
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• 제37권3호
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• pp.130-135
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• 2012

Objectives: The purpose of this study was to enhance curing light penetration through resin inlays by modifying the thicknesses of the dentin, enamel, and translucent layers. Materials and Methods: To investigate the layer dominantly affecting the power density of light curing units, resin wafers of each layer with 0.5 mm thickness were prepared and power density through resin wafers was measured with a dental radiometer (Cure Rite, Kerr). The dentin layer, which had the dominant effect on power density reduction, was decreased in thickness from 0.5 to 0.1 mm while thickness of the enamel layer was kept unchanged at 0.5 mm and thickness of the translucent layer was increased from 0.5 to 0.9 mm and vice versa, in order to maintain the total thickness of 1.5 mm of the resin inlay. Power density of various light curing units through resin inlays was measured. Results: Power density measured through 0.5 mm resin wafers decreased more significantly with the dentin layer than with the enamel and translucent layers (p < 0.05). Power density through 1.5 mm resin inlays increased when the dentin layer thickness was reduced and the enamel or translucent layer thickness was increased. The highest power density was recorded with dentin layer thickness of 0.1 mm and increased translucent layer thickness in all light curing units. Conclusions: To enhance the power density through resin inlays, reducing the dentin layer thickness and increasing the translucent layer thickness would be recommendable when fabricating resin inlays.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.375-376
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• 2010

본 연구는 WCP 대체율 및 오토클레이브 양생시간 변화에 따른 경량기포콘크리트의 미세구조 및 광물분석을 통한 화학적 특성을 검토하였다. 경화체의 미세구조 분석으로부터 수열 반응 후 WCP 대체율 및 양생시간에 관계없이 반응하여 판상형, 섬유형의 결정 구조물의 수화물을 형성한 것을 확인하였다. 또한 Tobermorite(C5S6H5)는 WCP의 구성성분인 결정질 Quartz의 반응에 의한 것으로 추정된다.

• Restorative Dentistry and Endodontics
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• 제25권3호
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• pp.482-486
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• 2000

The purpose of the present study was first, to evaluate the relationship between composite surface conversion and surface discoloration, second, to know if there was difference in surface discoloration between celluloid-strip-finished composite surface and polished surface. In addition, the discoloration of composite surface was also evaluated with visual inspection or digital camera with high resolution monitor, Z100, Tetric Ceram, Spectrum, and Aelitfil were used. The composite surfaces were celluloid-strip finished (group 1), polished (group 2), celluloid-strip finished under nitrogen gas purging (group 3) or only light cured without finishing or polishing under nitrogen gas purging (group 4). The microhardness of each samples were also measured in each group. The samples of each group were also divided into 4 subgroup whether they were immediately placed in disclosing solution (0.2% Elythrosin, pH 7.0) (subgroup1), 1 day after light curing(subgroup 2), 3day after light curing(subgroup 3) or 7 day after light curing(subgroup 4). The computer controlled spectrophotometer was used to determine CIELAB coordinates ($L^*$, $a^*$, $b^*$). The amounts of color difference were compared. The results were as follows; 1. There was no difference in discoloration between celluloid strip finished composite surface and polished surface. 2. The samples discolored more when they were placed in disclosing solution immediately after polymerization than other groups. 3. When the samples were light cured under nitrogen gas purging and without polishing process, they discolored more than other groups even though they showed higher micro hardness. 4. With visual inspection or digital camera, only a limited information was available in detecting composite surface discoloration.