有限要素法에 依한 陶材 金屬間의 應力 分析

朴贊云,裵泰聖,朴鍾萬 全北大學校 1988 論文集 Vol.30 No.-

Since the introduction of ceramo-metal system in dentistry, many investigators have attempted to measure the bond strengths between the porcelains and the alloys. In this paper, 3-point and 4-point flexure test of Ni-Cr plate, being used in this experiment, and ceramometal system were analyzed for displacements and stress distributions using finite element method(F.E.M).

영구치 구성 성분중 연 함량에 관한 연구

박찬운 全北大學校 齒醫學硏究所 1985 전북치대논문집 Vol.3 No.1

최근에 치질의 건강상태와 치질내 미량원소와의 관계가 상당한 관심의 대상이 되고 있으며, 특히 불소화합물과 반상치 및 항우식 예방효과의 관계 외에도 Se, Cd, Pb 등은 차아우식발생과 관계가 있다는 보고가 있으며, 치질을 구성하고 있는 대부분의 유기물 및 무기물과 치질의 발육 및 우식과의 관계가 검토의 대상이 되고 있다. 심지어는 지역적인 치질 우식증의 방생빈도간의 차이를 치질의 원소구성 차이로 설명하려는 시도도 있다. 이와같이 치질의 미량금속 원소함량은 역학적 요인에 따라 변동을 보일 수 있기 때문에 지역사회의 구강보건문제를 연구하기 위해서는 치질내 미량금속 원소의 구성에 관한 기초적인 자료가 필요하다. 본 연구에서는 그 중 Lead(납)을 우선 택하였다. EH한 치질구성 성분의 차이가 치질건강상태와 어떠한 관계가 있는가를 파악하여 치질의 건강상태를 항상 유지시키기 위하여 공중보건학적 및 구강보건학적 제반지침을 결정하는 것이 요구된다. 현금 우리나라의 경우 치질내 미량금속에 대한 연구는 비교적 드물고 특히 Pb에 관한 연구는 거의 없는 실정이다. 이에 영구치 구성성분 중 남 함량에 관한 자료를 제공하고자 본 연구를 시도하였다.

Cao-MgO-SiO₂-P₂O -CaF₂계 생체활성 결정화 유리의 기계적 성질에 미치는 ZrO₂및 Al₂O₃의 분산 강화 효과

박찬운,강건구,원대희,이민호,배태성 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.2

Bioactive glass-ceramics can form tight chemical bonds with bone, however, their poor mechanical properties may limit their clinical applications. Alumina ceramics show good biocompatibility and high strength but can't form chemical bonds with bone. Hydroxyapatite ceramics and bioglass form chemical bonds with bone but their strength and fracture are relatively low. Glass ceramics containing apatite and wollastonite crystals can form tight chemical bonds with bone and show relatively high strength and fracture toughness. Bioactive glass-ceramics toughened by alumina and tetragonal zirconia polycrystals show relatively high mechanical strength. Both bioactive and high strength ceramics will be widely applicable to many clinical applications. In this study, bioactive glass-ceramics toughened by alumina and zirconia polycrystals were fabricated, and crystallization behavior, biaxial flexure strength, fracture toughness, and bioactivity were measured. The results obtained were summarized as follows; 1. The major crystaline phase in the matrix glass were observed to be apatite, wollastonite, and β-TCP. 2. Biaxial flexure strength and fracture toughness values were more improved by the dispersion toughening of alumina and zirconia, and the improvement of mechanical strength was more higher in the dispersion toughening of zirconia than that of alumina. 3. The bioactivity, which was evaluted from apatite formation in the simulated body fluid, was higher in the dispersion toughening of Zr-O₂than that of Al₂O₃.

도재표면 처리제가 복합레진과 도재와의 결합에 미치는 영향

백명주,박주미,배태성,박찬운 全北大學校 齒醫學硏究所 1991 전북치대논문집 Vol.9 No.1

This study investigated the effect of porcelain primer on bonding of composite resin to porcelain surface. In order to test the bond strength between porcelain and composite resin, porcelain cylinders were embedded in acrylic resin, and polished with 240grit silicone carbide paper. The specimens were divided into twelve groups. All specimens were treated with three porcelain primers and bonded with five composite resins. All test groups were stored in 37℃ distilled water for 48hours. Shear bond strengths were measured with Instron(Model 4201) at a cross-head speed of 1㎜/min. The obtained results were as follows : 1. Scotchprime/SiluxⅡ group and BISCO Porcelain Primer/Bisfill group showed significant higher bond strengths than Clearfil Porcelain Primer/Photo clearfil Bright group(p<0.05). And there was no significant differences in bond strengths between Scotchprime/SiluxⅡ group and BISCO Primer/Bisfill group(p>0.05). 2. When composite resins were used with Scotchprime, the bond strengths were decresed SiluxⅡ(16.68±3.35 MPa), Bisfil(16.23±4.54 MPa), Poly-Fill(14.74±4.08 MPa), Photo Clearfil Bright(13.75±2.89 MPa) and Pekalux(14.74±4.08 MPa) in order, but there was no statistical significance(p>0.05). 3. When composite resins were used with BISCO Porcelain Primer, the bond strength were decreased Bisfil(16.17±1.60 MPa), SiluxⅡ(12.13±2.37 MPa), Poly-Fill(10.78±1.99 MPa), Photo Clearfil Bright(9.91±4.59 MPa) and Pekalux(7.36±2.16 MPa) in order, but there was no statistical significance(p>0.05). 4. SiluxⅡ, Photo Clearfil Bright and Poly-Fill used with Scotchprime showed significant higher bond strengths than BISCO Porcelain Primer(p<0.05).

수종 탄성의치상 이장재의 물리적 특성에 관한 실험적 연구

송윤관,박주미,송광엽,박찬운 全北大學校 齒醫學硏究所 1991 전북치대논문집 Vol.9 No.1

The purpose of the present study was to evaluate the effects of storage time and condition on the weight change, dimensional stability and softness of six commercially available soft lining materials. Ten specimens each 1.8㎜ in thickness of soft lining materials were bonded to poly(methylmethacrylate) made in the form of circular disk 50㎜ in diameter and 1.5㎜ in thickness using steel molds, then stored in simulated mouth condition(artificial saliva, pH 7.4, 37±1℃). The specimens were tested after 0, 1, 7, 14, 28, 42 and 56days. The data were analyzed by one way analysis of variance with Duncan's multiple range test. The results of this study were obtained as follows : 1. For permanent soft lining material Mollosil showed a significant decrease in weight after 42days, for provisional soft lining material Coe Comfort showed a significant increase in weight after 28days(p<0.05) between the aging times. 2. For permanent soft lining material Coe Soft showed a significant increase in dimensional change after 42days(p<0.05), but the other gorups showed no significant difference between the aging times(p>0.05). 3. For Molloplast-B material a significant difference in softness was not found between the aging times(p>0.05), Coe Super-Soft showed a significant decrease in softness after 7days, and Coe soft, Mollosil, Visco-gel and Coe Comfort showed a significant decrease in softness after 28days(p<0.05).

전장용 복합레진의 2축굽힘강도에 미치는 Thermal Cycling의 영향

백명주,배태성,박찬운 대한치과기재학회 2001 대한치과재료학회지 Vol.28 No.1

Effect of Thermal Cycling on the Strength of the veneering resin composites for crown. Four commercially available resin composites were used. Disc specimens were fabricated in the teflon mold giving a specimen size of 12mm in diameter and 1mm in thickness. In order to investigate the deterioration by thermal cycling test, biaxial flexure strength and Knoop hardness were measured. Thermal cycing test was conducted at 15 second dwell time each in 5℃ and 55℃ baths. Biaxial flexure test was conducted using the ball-on-three-ball method at the crosshead speed of 0.5mm/min, and Knoop hardness measurement was made under 25g load for 15 seconds. Fracture surfaces were examined by scanning electron microscope. The results obtained were summarized as follows; 1.The strength data were fit to single-mode Weibull distribution. Weibull modulus values of the DC and ET groups decreased after thermal cycling test, but the AG and TG groups increased. 2.The highest biaxial flexure strength of 169.96MPa was observed in the ET group after the thermal cycling test, and the lowest value of 52.54MPa was observed in the DC group. Biaxial flexure strengths showed the significant differences in each resin composite group(p<0.05). 3.Knoop hardness number of ET group after the thermal cycling test was the highest(148.79kg/㎟) among the resin composites, while that of the DC group was the lowest(23.56kg/㎟). Knoop hardness numbers showed the significant differences between the ET group and others, and also between the AG or TG group and DC group(p<0.05). 4.Observation of fracture surfaces revealed that cracks initiated from the center point where the maximum tensile stress was occurred and then propagated in the conical shape.

치과용 저온 및 초저온 용융형 도재의 파괴 특성 평가

송창용,배태성,박찬운 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.3

The purpose of this was to evaluate the fracture characteristics of dental low- and ultra low-fusing porcelains by Vickers indentation method. Three kinds of commercially available low-fusing porcelains of Ceramco (CN), Vintage (VT) and Omera 900 (ON) and three kinds of ultra low-fusing porcelains of Carmen (CM), Carrara (CR) and Finess (FN) were used as experimental materials. Disc specimens were prepared to the final dimensions of 12 mm in diameter and 2 ㎜ in thickness. Vickers indentations were made under a load range of 2.0∼9.8 N, and the hardness, fracture toughness and characteristic indentation dimensions were examined. The highest Vickers hardness value of 605.6 was obtained in the VT group and the lowest value of 544.8 was obtained in the CR group. Results of Tukey test showed that hardness values of the VT and CR groups were significantly different (p<0.05). The highest fracture toughness value of 1.06 MPa · m^1/2 was obtained in the VT group and the lowest value of 0.61MPa m^1/2 was obtained in the FN group. Results of Tukey test showed that an overall significant difference was indicated low-fusing porcelains were similar or inferior to those of low-fusing porcelains. The ratios of radial crack length c and of indentation load.

도재수복물의 표면 첨색시 온도에 따른 색조안정성과 표면조도의 평가

백은주,배태성,송광엽,박찬운 全北大學校 齒醫學硏究所 1991 전북치대논문집 Vol.9 No.1

The effects of oven firing on the color stability and surface texture of extrinsic stains used characterization and color modification of metal ceramic restoration were studied by comparing different temperatures and techniques. They were autoglaze technique, applied glaze technique, two step low-fusing glaze technique and one step low-fusing glaze technique. Autoglaze technique and applied galze technique were air-fired to manufacturer's recommended temperature. Two step low-fusing glaze technique is seperated staining and overglazing. Thin slurry of stain powder were air-fired to 1500℉. Overglaze powder was than mixed with stain medium and air-fired to 170℉. One step low-fusing glaze technique in combined staining and overglazing. Thin slurry of stain and glaze powder were air-fired to 170℉. The obtained results were as follows : 1. Slightly significant color differences by colorimeter were found between different stain application and fusion techniques(P<0.05). 2. Two step low-fusing glaze method showed the most rough surface, especially ceramco orange stain(P<0.05). 3. Surface roughness increased gradually in order of autoglaze, applied glaze, one step low-fusing glaze but they were not significantly different(P<0.05). 4. When two step low-fusing glaze was applied, both color measurement and surface texture were significantly different from other groups(P<0.05).

Mandibular overclosed patient를 위한 oral rehabilitation

송창용,김광석,이상돈,백희선,박찬운 全北大學校 齒醫學硏究所 1985 전북치대논문집 Vol.3 No.1

티타늄 레이저 용접부의 기계적 성질 평가

이중재,김길수,안승근,배태성,박찬운 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.2

This study was performed to examine the effects of laser output energy on the mechanical properties of laser-welded titanium joints. Titanium rods of 3 ㎜ in diameter were perpendicularly cut to 30 ㎜ in length for the laser welding. Two rods were fixed to each other with a jig and welded vertically using a Nd:YAG laser at output current of 210-270 A. The penetration depth of the laser beam against the titanium was measured with the changes of output current, pulse duration, and spot diameter. Mechanical tests included tensile testing and Vickers microhardness of the joints. Tensile testing was performed at the crosshead 00speed of 1.0 ㎜/min and a gauge length of 30 ㎜ with a universal testing machine. Vickers microhardness was mesured under 9.8 N load for 15 seconds. The results obtained were summarized as follows; With increasing the output current, the penetration depth of the laser to titanium was increased. Tensile strength values of laser-welded groups were the relatively higher than that of non-welded parent material group. There were significant differences in tensile strength between the specimens of laser-welded at output currents 250 A, 270 A and non-welded parent material group(p<0.05). Microhardness values were increased in the heat-affected zone. Brittle fracture regions were observed in the specimens of laser-welded at output currents 270 A.