• 대한치과기공학회지
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• 제35권4호
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• pp.287-293
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• 2013

Purpose: This study is to provide basic data of the dental acrylic denture base resin in the mechanical property difference investigation according to the monomer composition weight ratio of the acrylic denture base resin. Methods: The monomer composition of the acrylic denture base resin and weight ratio makes the different specimen. It measured the mechanical property with the specimens through Hardness Test, Tensile Test, Flexural Test, Flexural Modulus, FT-IR Test. Results: The control group Vertex was 18.4 Hv and the experimental group MED was 14.46~19.07Hv in the hardness test. Vertex was 364N, MED-3 was lowest in the tensile strength test and the Head of a family cursor declination was big. The result declination of the experimental specimens showed. Vertex and MED-2 was the highestest in the flexural test and after coming MED-6, MED-5, MED-1, MED-3, MED-4. Vertex and MED-2, as to a spectrum for $500{\sim}1800cm^{-1}$ peak can show the excellent degree of polymerization in the FT-IR Test. Conclusion: The ideal weight ratio of the monomer of the acrylic denture base resin of which the mechanical property is the highestest was MMA 100g, EDGMA 5g, DMA 0.2g, of MED-2.

• 대한치과기공학회지
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• 제8권1호
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• pp.23-29
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• 1986

One of the primary advantage of acrylic resin teeth is their ability to bond chemically to the denture base resins. But, occasionally, failure have been observed in which acrylic resin teeth break lose from the denture, indicating that chemical bonding does not always occur. The most probable explanation for this type of failure was the presence of a trace of wax remaining as a residue on the surfaces of the teeth after the boiling-out procedure which adgered to the tooth surface and prevented bonding. The purpose of this stdy was preparing the specimens of denture base resin with acrylic resin teeth that four treatment method to ridge lap portion of the tooth and investigated bond between the teeth and denture base resin with tensile strength. Compared results of tensile strength on test specimens were as follows: 1. The mean of strength among the four test groups showed the difference was significant enough(P 0.01). The order of its strength mean was methylene chloride treatment group, detergent solution treatment group, kerosene-ether treatment grgoup, boiling water only group. 2. In compared results between the wax eliminating method groups, there were significant difference between the boiling water only group and other groups(P 0.01), no significant difference were found in the wax eliminating method groups except boiling water only group(P 0.05).

• 대한치과보철학회지
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• 제41권3호
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• pp.360-368
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• 2003

Statement of Problem: The residual monomer of denture base materials causes hypersensitivity on oral mucosa and intereferes with the mechanical properties of the cured resin. The amount of residual monomer is influenced by materials, curing cycle, processing method, and etc. Purpose: The aim of this study was to investigate the residual methyl methacrylate(MMA) content of injection molded denture base polymer, and to compare this with the self-cured resin and the conventional compression molded heat-cured resin. Materials and Methods: Disc shaped test specimens (50mm in diameter and 3mm thick) were prepared in a conventional flasking technique with gypsum molding. One autopolymerized denture base resins (Vertex Sc. Dentimex. Netherlands) and two heat-cured denture base resins (Vertex RS. Dentimex. Netherlands, Ivocap. Ivoclar Vivadent, USA) were used. The three types of specimens were processed according to the manufacturer's instruction. After polymerization, all specimens were stored in the dark at room temperature for 7 days. There were 10 specimens in each of the test groups. 3-mm twist drills were used to obtain the resin samples and 650mg of the drilled sample were collected for each estimation. Gas chromatography (Agillent 6890 Plus Gas Chromatograph, Agillent Co, USA) was used to determine the residual MMA content of 10 test specimens of each three types of polymer. Results: The residual monomer content of injection molded denture base resins was $1.057{\pm}0.141%$. The residual monomer content of injection molded denture base resins was higher than that of compression molded heat cured resin ($0.867{\pm}0.169%$). However, there was no statistical significant difference between two groups (p>0.01). The level of residual monomer in self cured resin($3.675{\pm}0.791$) was higher than those of injection molded and compression molded heat cured resins (p<0.01). Conclusion: With respect to ISO specification pass / fail test (2.2% mass fraction) of residual monomer, injection molding technique($1.057{\pm}0.141%$) is a clinically useful and safe technique in terms of residual monomer.

• 대한치과기공학회지
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• 제31권4호
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• pp.37-43
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• 2009

This study evaluated the effect of concentration of glass fiber reinforcement on the flexural properties of auto and heat polymerized denture base resin. The test specimens($64{\times}10{\times}3.3mm$) were made of auto and heat polymerized resin(Vertex, Dentimax, Netherlands). Glass fiber(ER 270FW, Hankuk Fiber Glass, Korea) were used to reinforce the denture base resin. The 2.6%, 5.3% and 7.9% volume pre-impregnated fiber were located at the bottom of specimen. The test specimens(n=7) of each group were stored in distilled water at $37^{\circ}C$ for 50 hours before test. The flexural strength and modulus were measured by an universal testing machine(Z020, Zwick, Germany) at a crosshead speed of 5 mm/min in a three-point bending mode. The data was analyzed by one-way ANOVA and the Duncan's multiple range test(${\alpha}$=0.05). The difference of auto polymerized resin groups and heat polymerized resin groups were statistically analyzed by t-test(${\alpha}$=0.05). Glass fiber showed significant reinforcing effects on auto and heat polymerized resin. For flexural strength and modulus, auto polymerized resin was the highest in 7.9% volume, while heat polymerized resin was the highest in 5.3% volume. In this study, glass fiber at 7.9% volume ratio showed most effective reinforcing effect on auto polymerized resin and glass fiber at 5.3% volume ratio showed most effective reinforcing effect on heat polymerized resin in terms of flexural strength and flexural modulus.

• 대한치과보철학회지
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• 제37권2호
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• pp.235-241
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• 1999

The bond failure of resin teeth In denture base resin is one of the failure in prosthodontic treatment. The purpose of this study was to evaluate the bond strength of artificial resin teeth to the denture base resins. Specimens were made with heat curing acrylic resins (Vertex Rs, Lucitone 199) and artificial resin teeth (Tiger, Trubyte biotone, Endura, Orthosit, Tubyte bioform IPN) and the bond strength were measured with testing machine(Zwick. Germany) and the mode of bond failure were observed. The results were as follows; 1. The bond strength of Vertex Rs to artificial resin teeth was the highest in Tubyte biotone, and It was the lowest in Tiger and Trubyte bioform IPN. 2. The bond strength of Lucitone 199 to artificial resin teeth were higher in Orthosit and Trubyte bioform IPN than in Tiger and Trubyte biotone. 3. The bond strength of Trubyte biotone to Vertex Rs was higher than to Lucitone 199 and that of the Trubyte bioform IPN to Lucitone 199 was higher than to Vertex Rs. 4. Nearly all bond failures of specimens occured cohesively within the resin teeth.

• 대한치과보철학회지
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• 제39권1호
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• pp.49-57
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• 2001

The use of autopolymerizing-cured resin and light-cured resin for direct introral relining of complete and partial dentures has been popular. The purpose of this investigation was to determine the surface characteristics of autopolymerizing-cured reline resins(Tokuso rebase, Mild rebaron, Meta base) and light-cured reline resin(Mild rebaron LC). Acrylic resin slab specimens(1.0cm in diameter at the bottom, and 0.3cm high) were made against glass according to the instructions of the manufacturer following normal procedures for each of direct reline resins and examined the surface characteristics by use of surface profilometer and the other specimens which were made intraorally for each of direct reline resins were examined by use of scanning electron microscopy. The results were as follows : 1. Each surface roughness(Rz) of hard relin resins was $0.14{\pm}0.04{\mu}m$ in Tokuso rebase, $0.37{\pm}0.11{\mu}m$ in Mild Rebaron, $0.79{\pm}0.44{\mu}m$ in Mild Rebaron LC, $6.36{\pm}3.40{\mu}m$ in Meta base. There were significant differences between the surface roughness of Meta base and those of other reline resins(p<0.05) 2. The generation of porosity was the most in Tokuso Rebase and followed by Meta base, Mild Rebaron and Mild Rebaron LC in the order respectively. 3. Light-cured reline resin(Mild rebaron LC) was denser in surface than any other autopolymerizing-cured reline resins. Tokuso rebase and Mild rebaron was denser than Meta base. Conclusively, light-cured reline resin(Mild rebaron LC) had less porosity and better surface density than any other autopolymerizing-cured reline resins.

• 대한치과교정학회지
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• 제31권4호
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• pp.459-465
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• 2001

본 연구는 브라켓 간접부착술식시 치면과 레진 베이스의 간격 및 접착제에 따른 전단결합강도를 비교함으로써 브라켓 간접부착의 접착제로서 호제(paste)형 레진 병용의 타당성 여부를 평가해보고자 시행되었다. 소의 하악 중절치 120개를 실험재료로 하여 대조군의 경우 접착제로 실런트만을 사용하는 반면 실험군의 경우 실런트와 호제형 레진을 병용하여, 치면과 레진 베이스 간의 간격이 0.0, 0.2,또는 0.4 mm가 되도록 접착한 다음 만능물성 시험기를 이용하여 각 시편의 전단결합강도를 측정하고 비교하여 다음의 결과를 얻었다. 1. 치면과 레진 베이스 간의 간격이 멀어질수록 두 군 모두에서 전단결합강도가 감소하는 것으로 나타났다. 2. 치면과 레진 베이스 간의 간격이 0.0 mm인 경우 양 군 간의 전단결합강도의 차이는 나타나지 않았다. 3. 치면과 레진 베이스 간의 간격이 0.2, 0.4 mm인 경우 실런트와 함께 호제형 레진을 병용한 경우의 전단결합강도가 실런트만 사용한 경우에 비하여 통계적으로 유의하게 높게 나타났다. 이상의 연구결과는 브라켓 간접부착술식시 치면과 레진 베이스 간의 간격이 의심될 경우 브라켓 간접부착의 접착제로서 실런트만 단독 사용하는 것보다 호제형 레진을 병용하는 것이 유리함을 시사하였다.

• 한국응용과학기술학회지
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• 제24권3호
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• pp.253-263
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• 2007

Three different weather-resistant coatings were fabricated with the various weight ratios of a mill-base silicone/acrylic resin to let-down silicone /acrylic resin at 2:8, 3:7, and 4:6 respectively. The prepared coatings were tested to investigate the effect of composition of weather-resistant coatings on the physical properties. The thermal stability, salt spray exposure, and weather-resistance were improved with the increased silicone content. It was concluded that the optimum retio of mill-base silicone/acrylic resin to let-down silicone/acrylic resin would be 2:8 and the coating with 30 wt% of silicone content would have high weather-resistance.

• 치위생과학회지
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• 제10권6호
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• pp.445-450
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• 2010

본 연구에서는 열중합 의치상 레진에 유리 섬유, 아라미드 섬유, 폴리에틸렌 섬유를 2.6%, 5.3% 부피비로 첨가하여 섬유의 종류에 따른 강화효과를 평가하고, 각 섬유를 두 가지로 조합한 hybrid FRC를 제작하여 동일 함량의 단독 섬유 FRC보다 굴곡성질이 더 우수한지 평가하고자 하였다. 단독 섬유 FRC에서는 5.3% 부피비의 GL, PE 섬유군의 굴곡강도가 높게 나타났다. 두 가지 섬유 조합FRC의 굴곡강도는 단독 섬유 FRC보다 증가하는 양상을 보였으나, 5.3% GL, PE 섬유군과 유의한 차이가 없었다. 단독 섬유 FRC의 굴곡계수는 5.3% 부피비의 GL 섬유군이 가장 높게 나타났다. 두 가지 섬유 조합FRC의 굴곡계수는 단독 섬유 FRC의 5.3% GL 섬유군보다 높게 나타나 유의한 차이를 보였다. 열중합 의치상 레진의 강화를 위해 섬유를 단독으로 이용할 경우 5.3% 부피비로 첨가한 유리 섬유가 굴곡강도와 굴곡계수 면에서 효과적으로 적용될 수 있을 것으로 본다. 두 가지 섬유 조합FRC의 경우 굴곡강도 면에서는 강화효과가 크지 않았지만, 굴곡계수 면에서 볼 때 유리섬유를 하방에 아라미드 섬유를 그 상방에 위치 시킨 조합을 의치상의 강화에 효과적으로 적용할 수 있을 것으로 본다.

• The Journal of Advanced Prosthodontics
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• 제6권1호
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• pp.60-65
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• 2014

Teeth that have short clinical crown, which are not alone enough to support the definitive restoration can be best treated using the post and core system. The advantages of fiber post over conventional metallic post materials have led to its wide acceptance. In addition to that the combination of aesthetic and mechanical benefits of fiber post has provided it with a rise in the field of dentistry. Also the results obtained from some clinical trials have encouraged the clinicians to use the fiber posts confidently. Fiber posts are manufactured from pre-stretched fibers impregnated within a resin matrix. The fibers could that be of carbon, glass/silica, and quartz, whereas Epoxy and bis-GMA are the most widely used resin bases. But recently studies are also found to be going on for polyimide as possible material for the fiber post resin base as a substitute for the conventional materials.