• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.145-152
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• 1984

The purpose of this study was to compare combinations of the four visible light irradiating appliances (Translux, Heliomat, Pluraflex HL 150, Omega) and the four visible light activated composite resins (Durafil, Heliosit, Plurafil-super, Silux) to determine the depth of polymerization of each combination. Twenty samples were made with Durafil. Five samples were polymerized for 20 seconds using Translux, five with Heliomat, five with Pluraflex HL 150, five with Omega. Twenty samples were made with Heliosit, twenty with Plurafil-super, and twenty samples with Silux. A 20-second polymerization time was applied with each of 4 visible light irradiating appliances to 5 samples of each material. Eighty samples were treated in a like manner, but polymerization was extended to 40 seconds. Depth of polymerization were measured with caliper. The results were as follows. 1) Of the two time exposures, 40-second exposure provided a significantly greater depth of polymerization than 20-second for each light with each material. 2) Durafill-Translux system showed minimum depth of polymerization, and Plurafil-Pluraflex system showed maximum depth of polymerization. 3) Visible light irradiating appliances were able to harden the resins cured by tire visible lights of other makers' apparatuses. 4) In all circumstances, depth of polymerization was between 3.0-3.8mm.

• Restorative Dentistry and Endodontics
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• 제27권6호
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• pp.561-568
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• 2002

Purpose of this research is estimating polymerization depth of different source of light. XL 3000 for halo-gen light, Apollo 95E for plasma arc light and Easy cure for LED light source were used in this study. Different shade (B1 & A3) resin composites (Esthet-X, Dentsply, U.S.A.) were used to measure depth of cure. 1, 2, and 3 mm thick samples were light cured for three seconds, six seconds or 10 seconds with Apollo 95E and they were light cured with XL-3000 and Easy cure for 10 seconds, 20 seconds, or 40 seconds. Vicker's hardness test carried out after store samples for 24 hours in distilled water. Results were as following. 1. Curing time increases from al1 source of lights, oui$.$ing depth increased(p<0.05). 2. Depth (that except 1mm group and 2mm group which lighten to halogen source of light) deepens in all groups, Vickers hardness decreased(p<0.05). 3. Vicker's hardness of A3 shade composite was lower in all depths more than B1 shade composites in group that do polymerization for 10 seconds and 20 seconds using halogen source of light(p<0.05), but group that do polymerization lot 40 seconds did not show difference(p>0.05). 4. Groups that do polymerization using Plasma arc and LED source of light did not show Vicker's hardness difference according to color at surface and 1mm depth(p>0.05), but showed difference according to color at 2mm and 3mm depth(p<0.05). The results showed that Apollo 95E need more polymerization times than manufacturer's recommendation (3 seconds), and Easy cure need polymerization time of XL-3000 at least.

• 대한소아치과학회지
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• 제25권2호
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• pp.368-382
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• 1998

The purpose of this study is to evaluate and compare the results of argon laser for 5 seconds, argon laser for 10 seconds, and visible light for 40 seconds photo-polymerization in compressive strength, microhardness, curing depth, temperature rising during polymerization, and polymerization shrinkage. Hybrid type composite resin(Z-100) and compomer(Dyract) were used to be compared. The compressive strength was measured by an Instron(1mm/min cross head speed) in 60 specimens and the microhardness of the surface was expressed by Vickers Hardness Number(VHN) in 30 specimens. The curing depth was evaluated comparing the different values of upper and lower VHN according to irradiation time and thickness for the light source polymerization in 60 specimens. The temperature rising during photopolymerization was observed by the temperature change with thermocouple sensitizer beneath 40 specimens at the argon laser for 10 seconds and visible light 40 seconds irradiation. The polymerization shinkage was evaluated by calculating the decrease of % volume by using a dilatometer in 30 specimens. The results were as follows ; 1. In the case of compressive strength, the argon laser polymerization groups were higher than visible light group in Z-100 (p<0.05). In Dyract, the argon laser 5 seconds group did not show a significant difference with the visible light 40 seconds group. The argon laser 10 seconds group showed the markedly low value when compared with other groups (p<0.05) 2. In microhardness, Z-100 was better than Dyract when comparing by VHNs (p<0.05); however, there was not a significant difference between two materials in the visible light 40 seconds group and the argon laser 10 seconds group. 3. In the study of curing depth, Z-100 showed the consistent polymerization in argon laser irradiation because there was no difference in the VHN decrease according to the thickness change. Over the thickness control, the results did not show a significant difference between visible light and argon laser group in Z-100; however, in the case of Dyract, the visible light 40 seconds group was better than the argon laser groups(p<0.05). 4. There was a significant difference between the two materials in temperature rising during polymerization (p<0.05), but not a significant difference between irradiation times, 5. There was not a significant difference between the two materials in polymerization shrink age. The argon laser 5 seconds group was smaller than the other groups (p<0.05). It could be concluded that Z-100 polymerization was recommended to use the argon laser for reduction of the irradiation time while Dyract was recommended to use the visible light polymerization.

• 공업화학
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• 제16권5호
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• pp.672-676
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• 2005

치아수복용 고분자 복합체(polymeric dental restorative composite, PDRC)의 전치부와 구치부에의 응용 가능성을 높이고자 PDRC를 구성하는 실리카 충진재를 다양한 온도에서 열처리시켜 siloxane 기로 연결된 구조의 개질된 실리카를 제조하고 이를 PDRC 제조에 사용하였다. 제조된 PDRC의 중합 특성을 중합전환률, 중합깊이, 그리고 체적 중합수축률 등을 분석하여 고찰하였다. 실험 결과, 사용된 실리카의 열처리 온도가 높아짐에 따라 제조된 PDRC의 중합깊이는 감소하였고 체적 중합수축률과 중합전환률 값은 실리카 입자의 평균크기 감소에 따른 PDRC 내 resin matrix의 상대적 양의 증가로 인해 일정하게 증가함을 알 수 있었다.

• Restorative Dentistry and Endodontics
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• 제29권2호
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• pp.191-199
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• 2004

The purposes of this study were to estimate the material properties of the recently developed domestic composite resins for core filling material (Chemical, Dual A, Dual B；Vericom, Korea) and to compare them with other marketed foreign products (CorePaste, Den-Mat, USA；Ti-Core, Essential Dental Systems, USA；Support. SCI-Pharm. USA). Six assessments were made：working time. setting time. depth of polymerization. flexural strength. bonding strength. and marginal leakage. All items were compared to ISO standards. All domestic products satisfied the minimum requirements from ISO standards (working time：above 90 seconds. setting time：within 5 minutes). and showed significantly higher flexural strength than Core Paste. Dual A and B could. especially. reduce the setting time to 60 seconds when cured with $600mW/cm^2$ light intensity. All experimental materials showed 6 mm depth of polymerization. Bond strengths of Ti-Core and Dual B materials were significantly higher than the other materials. Furthermore. three domestic products and Ti-Core could reduce the microleakage effectively.

• 분석과학
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• 제17권3호
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• pp.225-229
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• 2004

UV 경화반응에 의하여 형성된 코팅의 성질을 향상시키기 위하여 첨가제로 사용한 실리콘 아크릴레이트가 광중합 반응에 미치는 영향을 마이크로 라만 분광법을 사용하여 관찰하였다. 광중합 반응의 반응체는 아크릴계 올리고머와 모노머를 사용하였으며 광 개시제로는 Darocur 1173을 사용하였다. 첨가제 실리콘 아크릴레이트는 광 경화 수지에 각각 0-3 wt% 첨가하였으며, UV를 조사하여 중합 반응시킨 후 공기-박막 경계면으로부터 두께에 따른 라만 스펙트럼을 관찰하였다. 광중합 반응의 진행정도는 1410과 $1635cm^{-1}$에 나타나는 중합에 직접 관여하는 아크릴기 ($-C=CH_2$)와 관련된 띠의 세기로부터 구하였다. 관찰된 결과에 따르면 마이크로라만으로부터 얻은 심도 스펙트럼 (depth profile)은 두께에 따른 경화반응의 진행 정도를 관찰할 수 있을 뿐만 아니라 경화 반응에 미치는 여러 요인에 대한 이해를 돕는 좋은 방법이 될 수 있음을 알 수 있다.

• Restorative Dentistry and Endodontics
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• 제39권4호
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• pp.310-318
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• 2014

Objectives: This study examined the influence of the resin thickness on the polymerization of silorane- and methacrylate-based composites. Materials and Methods: One silorane-based (Filtek P90, 3M ESPE) and two methacrylate-based (Filtek Z250 and Z350, 3M ESPE) composite resins were used. The number of photons were detected using a photodiode detector at the different thicknesses (thickness, 1, 2 and 3 mm) specimens. The microhardness of the top and bottom surfaces was measured (n = 15) using a Vickers hardness with 200 gf load and 15 sec dwell time conditions. The degree of conversion (DC) of the specimens was determined using Fourier transform infrared spectroscopy (FTIR). Scratched powder of each top and bottom surface of the specimen dissolved in ethanol for transmission FTIR spectroscopy. The refractive index was measured using a Abbe-type refractometer. To measure the polymerization shrinkage, a linometer was used. The results were analyzed using two-way ANOVA and Tukey's test at p < 0.05 level. Results: The silorane-based resin composite showed the lowest filler content and light attenuation among the specimens. P90 showed the highest values in the DC and the lowest microhardness at all depth. In the polymerization shrinkage, P90 showed a significantly lower shrinkage than the rest two resin products (p < 0.05). P90 showed a significantly lower refractive index than the remaining two resin products (p < 0.05). Conclusions: DC, microhardness, polymerization rate and refractive index linearly decreased as specimen thickness linearly increased. P90 showed much less polymerization shrinkage compared to other specimens. P90, even though achieved the highest DC, showed the lowest microhardness and refractive index.

• 대한소아치과학회지
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• 제31권2호
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• pp.280-289
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• 2004

치과용 수복재료가 요구하는 심미성과 치아의 보존 및 편의성 등의 여러 조건들을 만족시키기 위해서 치과용 복합레진은 적절한 중합이 이루어져 물리적 기계적 성질을 충족하고, 색조의 안전성, 중합시의 수축과 이에 따른 변연 적합도 문제를 해결할 수 있어야 한다. 본 연구에서는 광중합 복합레진 Z250의 색상과 두께를 달리 하여 광투과도와 중함도를 각각 적외선 분광분석법과 미세경도 측정을 통해 비교하여 다음과 같은 결과를 얻었다. 1. 플라즈마 아크 중합기의 사용 시 3초 중합과 6초 중합의 경우로 나누어 실험하였으며 6초 중합에 있어서 할로겐 중합 20초와 유사한 광투과도 및 미세경도를 나타내었다. 2. 광중합 복합레진의 색상을 A1, A2, A3, A3.5로 나누어 실험한 결과 레진의 표면에서는 색상별로 광투과도나 경도의 차이가 나타나지 않았으나, 2, 3, 4mm로 깊이가 증가함에 따라 색상에 따른 광투과도나 경도의 차이가 확연하게 나타났고 특히 색상이 어두워질수록 4mm의 깊이에서 중합도가 더욱 낮았다. 3. 중합깊이의 비교를 위하여 0, 2, 3 4mm깊이로 나누어 실험한 결과, 2mm이상의 깊이에 있어서는 미반응 단량체의 양이 유의하게 많은 것으로 나타났다. 4. 광중합 복합레진의 광투과도를 알아보는 FTIR을 통한 단량체 전환도와 미세경도 측정사이에는 유의한 상관관계를 보였다.

• 대한치과기공학회지
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• 제44권3호
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• pp.76-80
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• 2022

Purpose: The purpose of this study is to analyze the depth according to curing using photocurable resin for dental three-dimensional printing. Methods: A stainless mold with a height of 4 mm was prepared. Ultraviolet (UV) polymerization resin was injected into the mold. Photocuring was then performed for 5 minutes using a photopolymerizer, and the height was measured using a digital measuring instrument (first group). Second, light polymerization was also performed outside the mold for 5 minutes, and the height was measured using a digital measuring instrument. Third, light polymerization was further performed for 5 minutes, and the height was measured using a digital measuring instrument. Statistical analysis was performed with the Kruskal-Wallis test, which is a nonparametric test (α=0.05). Results: The third group had the largest measurement length, whereas the first group had the smallest. However, the difference between groups was not statistically significant (p>0.05). The color of the first group was different from that of the second and third groups. Conclusion: All of the 4-mm-thick photocured specimens had a curing reaction, but the part that was not directly irradiated with UV did not show its original color.

• 대한소아치과학회지
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• 제32권3호
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• pp.481-490
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• 2005

본 연구는 복합레진 중합 시 발생되는 중합수축이 C-factor에 의해 어떻게 영향 받는지 그리고 적층충전이 중합수축에 어떻게 영향을 미치는지 알아보고자 시행되었다. 세 가지 다른 깊이의 시편을 비교하였으며, 충전방법에 따른 비교를 위해 5가지 다른 충전방법에 따른 수축응력을 스트레인 게이지(Strain guage)를 사용하여 측정하였다. 이상의 실험을 통해 얻은 결과는 다음과 같다. 1. 와동깊이에 따른 수축응력을 측정한 결과 2mm와 3mm 시편에서는 800초 후 수축응력이 $2.18{\pm}0.23MPa$과 $2.38{\pm}0.07MPa$로 유의한 차이가 없었다(P>0.05). 2. 4mm 시편에서 800초 후 수축응력은 $1.99{\pm}0.24MPa$로 가장 낮은 수축응력을 보였다 (P<0.05). 3. 중합정도를 확인하기 위한 미세경도 실험결과 2mm와 3mm 시편에서는 상면과 하면의 미세경도 차이가 20% 내외로 양호한 중합상태를 보여주었으나, 4mm 시편에서는 상면과 하면의 미세경도가 현저한 차이를 보여 불완전한 중합이 이루어졌음을 알 수 있었다(P<0.05). 4. 충전방식에 따른 수축력의 차이를 비교한 결과 flowable resin을 이장하고 bulk로 충전한 제 5군에서 가장 낮은 수축응력을 보였으며, 제 1군(bulk충전)과 4군(oblique 적층충전)이 유사한 정도의 수축응력을 보였고, horizontal과 vertical하게 적층충전한 제 2군과 3군에서 가장 큰 수축응력이 관찰되었다(P<0.05).