• 응용화학
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• 제9권2호
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• pp.25-28
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• 2005

To evaluate the dental restorative application of polymer composites filled with hydroxyapatite (HAP) which is an inorganic component of human bone material, dental properties of the polymer composites were investigated. A visible light system was utilized to activate the acrylate resin matrix of the composites. Maximum loading percentage of HAP in composite was 65 wt% and the depth of cure was 6.0 mm which can be applicable for dental restoration. With increasing the HAP content, degree of conversion of polymer composites was slightly decreased, however, polymerization shrinkage value was not varied. Diametral tensile strength value was enhanced with an increase of HAP content, however, there was no strict trend between flexural strength and HAP concentration. Anyhow, polymer composites prepared herein have superior mechanical properties sufficient specifications applicable to dental materials.

• 폴리머
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• 제30권2호
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• pp.135-139
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• 2006

인체 뼈의 주성분인 수산화인회석(hydroxyapatite, HAP)이 충전된 고분자 복합체를 제조하고 이들의 치과적 물성을 분석하여 치과용 수복재료로의 응용성을 확인하고자 하였다. 복합체 제조에 사용된 기질인 아크릴계 단량체는 가시광선으로 경화시켰다. 실험 결과, HAP는 무게비로 65%까지 첨가되었으며 중합깊이는 6.0 mm 정도로서 일반적 치과용 수복재료로의 응용이 가능함을 확인하였다. 제조된 고분자 복합체의 중합전환율은 HHP 첨가량이 늘어날수록 약간 감소하였으며 중합수축률은 HAP 변화량에의 의존성이 거의 없었다. 복합체의 기계적 물성은 HAP함량이 증가할수록 간접인장강도는 증가하였고 굴곡강도는 큰 변화가 없었다. 그러나 그 값들은 치의학에서 규정한 값들을 상회하여 치과용 재료로의 응용 가능성이 매우 높음을 확인할 수 있었다.

• 대한치과의사협회지
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• 제37권10호통권365호
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• pp.785-795
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• 1999

• 대한치과기공학회지
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• 제40권4호
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• pp.231-237
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• 2018

Purpose: The development of the dental technology industry has digitized the dental process. Definition of Digitalization of Dental Implantation Digitalization is the process of model making and prosthodontic processing using 3D CAD and CAM. Currently, it is becoming popular due to the spread of various devices. However, precision evaluation at this stage is an important factor in precision-based dental procedures. Therefore, in this study, we want to analyze the precision of the processed body made with digital dental machine. Methods: The accuracy of digital dental pore devices was evaluated. Specimens were fabricated with 5 types of 3D printers. The external shape was measured with the prepared specimen. The surface roughness was measured. Results: As a result, precision was excellent in order of EP2 specimen, EP1 specimen, and EA2 specimen. The precision of EP3 specimen and EA1 specimen is not excellent. And the precision of the specimen processed with polymer 3D printer is excellent. The accuracy of LCPS type polymer 3D printers is considered to be excellent. Conclusion : 1. Observation of the shape The 3D printer for LCPS system and the 3D printer for SLM $40{\mu}m$ system were found to be precisely processed. 2. Surface roughness results The LCPS system polymer 3D printer has been shown to have a precise surface.

• 대한치과의사협회지
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• 제53권3호
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• pp.178-186
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• 2015

Dental polymer-based luting materials are classified into esthetic resin cement, adhesive resin cement and self-adhesive resin cement. Due to the different component of each type of resin cement, the preconditioning method of tooth surface and the steps are different from each type of resin cement. The pre-treatment of adherend (ceramic, resin and metal) surface also varies with the type of resin cement and the manufacturer. In this study, the characteristics of each type of resin cement, mechanical properties, indication and advantages were investigated. Through these, clinical tips on using resin cements were suggested.

• 폴리머
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• 제31권2호
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• pp.141-147
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• 2007

치아 수복용 충전제로서 인체 뼈의 주성분인 수산화인회석(hydroxyapatite)이 혼성화된 바륨실리케이트 (barium silicate, BaSi)를 사용하여 제조한 고분자 복합체의 치과적 물성을 분석하였다. 복합체 제조에 사용된 아크릴계 기재는 가시광선을 사용하여 경화시켰다. 실험 결과, 혼성화된 충전제 내에서의 BaSi 함량이 증가할수록 복합체의 기계적 강도는 일정하게 증가하였으며 치의학에서 규정한 값들을 상회하여 치아 수복재료로 충분한 값임을 확인할 수 있었다. 그러나 충전제 내에서의 BaSi 함량 증가에 따른 복합체의 내마모도는 약간 감소하였다. 한편, 복합체의 중합깊이는 충전제의 구성비에 관계없이 $6\sim9mm$ 정도로서 일반적 치과용 수복재료로 충분한 값들임을 확인하였으며 중합전환율과 중합수축률은 충전제 구성비에의 직접적 의존 경향성은 거의 없음을 확인할 수 있었다.

• 대한치과의사협회지
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• 제56권3호
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• pp.167-174
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• 2018

The development of dental materials has widened the scope of materials by changes in processing methods. CAD/CAM processing enables the use of zirconia as a dental material. Recent esthetic materials development has been made. For aesthetic purposes, a block for CAD/CAM processing by mixing polymer and ceramic materials are fabricated. However there is no guideline of how these materials should be used in actual clinical practice. Mechanical properties, wear and clinical studies were reviewed.

• 한국표면공학회지
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• 제43권3호
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• pp.132-141
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• 2010

NiTi alloy has been used for orthodontic wire due to good mechanical properties, such as elastic strength and frictional resistance, combined with a high resistance to corrosion. Recently, these wire were coated by polymer and ceramic materials for aesthetics. The purpose of this study was to investigate surface characteristics of polymer coated NiTi alloy wire for orthodontics using various instruments. Wires (round type and rectangular type) were used, respectively, for experiment. Polymer coating was carried out for wire. Specimen was investigated with field emission scanning electron microscopy(FE-SEM), energy dispersive x-ray spectroscopy(EDS) and atomic force microscopy(AFM). The phase transformation of non-coated NiTi wire from martensite to austenite occurred at the range of $14{\sim}15^{\circ}C$, in the case of coated wire, it occurred at the range of $16{\sim}18^{\circ}C$. Polymer coating on NiTi wire surface decreased the surface defects such as scratch which was formed at severe machined surface. From the AFM results, the average surface roughness of non-coated and coated NiTi wire was 13.1 nm, and 224.5 nm, respectively. From convetional surface roughness test, the average surface roughness of non-coated and coated NiTi wire was $0.046{\mu}m$, and $0.718{\mu}m$, respectively.

• 대한치과기공학회지
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• 제41권3호
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• pp.203-209
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• 2019

Purpose: The purpose of this study was to investigate the mechanical properties of polymer prosthetic and restorative materials for dental CAD/CAM using two test method; surface characteristics and shear bond strength. Methods: Commercialized CAD/CAM polymer blanks were investigated; One kinds of PMMA, and one PEKK blanks. A total of 20 PMMA and PEKK specimens were prepared, and each group was divided into 10 specimens. Average surface roughness was observed under surface profilometer. The contact angle was measured with a surface electrooptics. The bond strength was evaluated by a universal testing machine at a crosshead speed of 5mm/min. The data were statistically analyzed using independent t-test and Fisher's exact test(P<0.05). Results: The PMMA and PEKK group showed a significant difference in the shear bond strength with the composite resin(P<0.05). The surface roughness of the PEKK group was higher than that of the PMMA group. The fracture mode were observed in PEKK groups with 50% showing adhesive remnant index score. Conclusion: PEEK is used as substructure material and composite veneering material is applied. PEKK resins will contribute to the development of successful products that will provide structural and aesthetic satisfaction.

• 공업화학
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• 제17권4호
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• pp.403-408
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• 2006

가시광선 중합형의 고분자계 치아수복재의 고기능화를 위해 충전제로 사용된 친수성의 실리카 나노입자 표면을 $\gamma$-methacryloxypropyltrimethoxysilane ($\gamma$-MPS) 결합제로 소수성 처리하여 치아수복용 고분자 복합체를 제조하였다. 처리된 실리카의 구조적 물성과 복합체 내에서의 분산도 및 복합체의 중합 특성 등을 실리카의 소수화도와 비교하여 고찰하였다. 그 결과, 사용된 $\gamma$-MPS의 양이 40 wt%까지 증가함에 따라 실리카의 소수화도가 증가하였으며 그 이상에서는 큰 변화가 없었다. 또한 소수화도가 향상됨에 따라 복합체 내에서의 충전제 분산도가 양호하였으며 광중합 후 미반응 단량체는 핵자기공명 분석 결과 거의 남아 있지 않아 중합 특성이 우수함을 확인하였다.