• Title/Summary/Keyword: polished surfaces

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A study on the surface roughness assessment of polished surfaces (연마 다듬질 가공면의 표면 미세형상 평가에 관한 연구)

  • 조남규;김현국;권기환;한창수;안유민;이성환;박균명
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2000.10a
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    • pp.326-331
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    • 2000
  • This paper describes the statistical analysis techniques for the surface roughness assessment of polished surfaces. In experiments, the polishing process of the sample surfaces which are manufactured by ball end mill is consist of two steps; the cusp removal process and the surface finishing process. For the cusp removal process, the criterion of cusp removal was established from the power spectrum analysis to assess the change of the cusp removal rate. For the finishing process, the surface was polished by the rotational CBN tool and vibration wood tool. And the surface quality of polished surface was assessed using the functional parameters based on the statistical values of surface profiles. Consequently, the surface finish performance of the polished surface using the vibration wood tool was improved.

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A STUDY ON THE ROUGHNESS OF THE RESTORATIVE COMPOSITE RESIN (수복용(修複用) 복합(復合)레진의 표면조도(表面粗度)에 관(關)한 연구(硏究))

  • Lee, Myung-Jong
    • Restorative Dentistry and Endodontics
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    • v.13 no.2
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    • pp.207-220
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    • 1988
  • The purpose of this study was to measure roughness on the polished surfaces of composite resin, and was to observe the polished surfaces under Scanning Electron Microscope. The surface roughness tester (Surfcom 700A Semitsu Profilometer Tokyo. Japan) was used to measure roughness of polished surfaces. In this study, 4 brands of composite resin were examined, Pyrofil bond anterior Bell-Feel anterior Clearfil F II and Microrest A.P. White point, Silicone point, Super snap, and Sof-Lex medium disc as cutting instrument, and celluloid matrix were used. The results obtained were as follows. 1) The celluloid matrix produced the smoothest surfaces. 2) Microrest composite resin had smoother surface than any other composite resins after polishing. 3) The values of surface roughness made by White point, Silicon point and Super snap were similar. 4) The surfaces made by Sof-Lex medium disc was smoother than the surfaces made by any other polishing instruments.

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IR Transmittance and Surface Structure of Diamond Film Polished by Thermomechanical Method (열기계적으로 연마한 다이아몬드 막의 적외선 투과도 및 표면구조)

  • 정상기;최시경;정대영;최한메;권순용
    • Journal of the Korean Ceramic Society
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    • v.32 no.6
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    • pp.697-702
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    • 1995
  • The rough growth surfaces of diamond films fabricated by the hot filament CVD were polished using thermomechanical polishing method. And then, its application to the optical windows was discussed through the measurement of transmittance in the range of infrared radiation and analysis of surfaces structure. The results were compaerd with those of the films polished with conventional mechanicla polishing. The transmittance of the mechanically polished film reached 57~66% over the whole range from 500 to 4000 cm-1. But the transmittance of the film polished with thermomechanical polishing method was reduced below 35%. This decrease in transmittance was due to both the graphitization of diamond on the polished surface and the growth of $\beta$-SiC at diamond/Si interface during polishing. The residual Fe in hte thermomechanically polished surface was confirmed by SIMS analysis. This Fe played the role of the graphitization of near surface region of the diamond film.

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A STUDY ON THE ROUGHNESS OF THE VISIBLE LIGHT CURED COMPOSITE RESINS (가시광선(可視光線) 중합형(重合型) 복합(複合)레진의 표면조도(表面粗度)에 관(關)한 연구(硏究))

  • Lee, Myung-Jong
    • Restorative Dentistry and Endodontics
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    • v.16 no.2
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    • pp.197-212
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    • 1991
  • The purpose of this study was to roughness on the polished surface of visible light composite resins and was to observe the polished surfaces under Scanning Electrom Microscope(ISI DS 130 AKASHI Co. JAPAN). The surface roughness tester(Surfcom 700A Seimtsu profilometer Tokyo, Japan) was used to measure roughness of polished surfaces. In this study, 5 brands of visible of composite resins were examined, Pyrofile light bond Anterior Lite fil anterior Photo clearfil anterior & posterior Palfique light Anterior and posterior Silux Anterior. White point, Silicure point, Super snap Sof-Lex medium disk as cutting instrument, and celluloid matrix were used. The results obtained were as follows. 1. The Celluloid matrix produced the smoothest surfaces. 2. The surfaces made by Soflex medium disk was smoother than the surfaces made by any other polishing instruments. 3. The values of surface roughness made by White point, Silicon point and Super snap were similer. 4. Palfique light (AP) visible light composite resin showed the smoothest surface after polishing with Silicone point, Super snap disk and Soflex mediuem disk in all tested materials.

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In vitro study of Streptococcus mutans adhesion on composite resin coated with three surface sealants

  • Kim, Da Hye;Kwon, Tae-Yub
    • Restorative Dentistry and Endodontics
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    • v.42 no.1
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    • pp.39-47
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    • 2017
  • Objectives: Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans) on the dental composite resins coated with three commercial surface sealants. Materials and Methods: Composite resin (Filtek Z250) discs (8 mm in diameter, 1 mm in thickness) were fabricated in a mold covered with a Mylar strip (control). In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP). The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9). Results: Group OG achieved the lowest water contact angle among all groups tested (p < 0.001). The cell surface of S. mutans tested showed hydrophobic characteristics. Group PoGo exhibited the greatest bacterial adhesion among all groups tested (p < 0.001). The sealant-coated groups showed statistically similar (groups PS and FP, p > 0.05) or significantly lower (group OG, p < 0.001) bacterial adhesion when compared with the control group. Conclusions: The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo.

A STUDY ON THE GLOSS AND ROUGHNESS OF THE COMPOSITE RESIN (복합레진의 광택 및 표면조도에 관한 연구)

  • Cho, Seung-Joo;Lee, Myung-Jong
    • Restorative Dentistry and Endodontics
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    • v.15 no.1
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    • pp.67-80
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    • 1990
  • This study was performed for elucidating the effects on surface polishing of composite resins. In this study, Silux(microfilled), Graft(hybrid), Bisfil- I (hybrid posterior) and Hi-pol(conventional) were used. Sixty specimens were made with 4 brands of composite resins and Optilux system in $2.0{\times}1.3{\times}1.0cm$ resin block which has a cavity with 0.5cm diameter and 0.5cm depth. Polishing was done with #600 sand paper and Soflex, Super-snap, Micron finishing system, or Composite polishing kit. Final polished surfaces were measured by roughness tester(Kasaka Lab. Ltd., Japan) and image analyser(Omnimet Image Analyser, Buehler, USA). The results were as follows, 1. The celluloid strip produced the smoothest surfaces. 2. Light curing microfilled composite resin, Silux, had smoother surface than any others. 3. The surfaces polished by Soflex were smoothest. 4. Aluminum oxide disk, Soflex and Super-Snap, made smoother surface than diamond bur, M.F.S., or silicon point, Composite polishing kit. 5. The roughness values of surface polished by M.F.S. composed of diamond burs, were less than those of Composite polishing kit made from silicone points.

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The Validation of Newly Developed Portable Slipmeter (새롭게 개발된 휴대용 미끄럼 저항 측정기의 성능검증)

  • Kim, Jung-Soo
    • Journal of the Korean Society of Safety
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    • v.28 no.1
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    • pp.18-23
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    • 2013
  • The purpose of this study were to develop and validate a prototype slipmeter used on-site floor. The developed slipmeter was dreg sled type. It measured static coefficient of friction(SCOF). The developed slipmeter was evaluated with ASTM 2508-11 which use four different standard surfaces(polished granite, glazed porcelain, vinyl composite tile, and ceramic tile). The SCOF was then measured with developed slipmeter under the three different contaminants and seven different floors. The test results of slipmeter were also compared with those of BOT-3000, floor surface roughness, and human perception. The test results revealed that developed slipmeter successfully ranked all four standard surfaces and differentiated among standard surfaces with varying degrees of slipperiness. The developed slipmeter couldn't properly measure slipperiness under the two kind of floors(polished tile, ground steel plate) and one kind of contaminant(glycerol). The test results of developed slipmeter had stronger correlation with those of BOT-3000 and floor roughness under the water and detergent solution than under the glycerol. The test results of developed slipmeter also showed stronger correlation with those of BOT-3000 and surface roughness than those of human perception. The newly developed slipmeter had been found to give consistent results under the test conditions except for two kind of floors(polished tile, ground steel plate) and one kind of contaminant(glycerol).

SURFACE ANALYSIS OF CERCE RESTORATIONS POLISHED BY DIFFERENT TECHNIQUE (연마방법에 따른 Cerec block의 표면 거칠기 비교)

  • Kim, Sung-Gwang;Vang, Mong-Sook
    • The Journal of Korean Academy of Prosthodontics
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    • v.35 no.1
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    • pp.31-42
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    • 1997
  • This study was performed to investigate the surface roughness of the Cerec Vita Mark II polished by various polishing techniques, compare with that of the Vintage enamel porcelain glazed by high temperature glazing technique. All of the Cerec specimen were finished with sequential use of high speed diamond burs(grit 45, 30 and $15{\mu}m$). The groups were divided into 5 groups : Group I : Cerec Vita Mark II block specimens polished with Sof-lex discs. Group II : Cerce Vita Mark II block specimens polished with Two Striper MPS. Group III : Cerce Vita Mark II block specimens polished with Enhance. Group IV : Cerce Vita Mark II block specimens polished with Porcelain laminate polishing FG kit. Group V : Vintage enamel porcelain glazed by high temperature glazing Technique. Each group was consisted of 10 specimens. The surfaces produced were examined quantitatively using a laser specular reflectance machine(Perthen RM600-s, Feinpruf Perthen GmbH., Germany) and qualitatively under SEM(JSM-5400, JEOL, Japan). The Results were as follows : 1. The arithmetic mean roughness value(Ra) in groups 1, 2, 3 and 4 was higher than that of group5. There was statistically significant difference(P<0.05). 2. The arithmetic mean roughness value(Ra) decreased in the following orders : group 1, group 2, group 4, group 3 and there was no statistically significant difference between group 1 and group 2, group 3, and group 4. There was statistically significant difference among group 1, 2, and group 3, 4 and group 5(P<0.05). 3. The maximum individual peak-to-valley-height(Rmax) decreased in the following orders : group 2, group 1, group 4, group 3, group 5 and there was no statistically significant difference between group 1 and 2, group 1 and group 4, group 3 and group 5. There was statistically significant difference among group 1, 2, and group 1, 4 and group 3, 5(P<0.05). 4. The treated surfaces of group 5 had smoother surface than that of groups 1, 2, 3, 4 with SEM.

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CMP (Chemical Mechanical Polishing) characteristics of langasite single crystals for SAW filter applications

  • Jang, Min-Chul;An, Jin-Ho;Kim, Jong-Cheol;Auh, Keun-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.10 no.4
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    • pp.309-317
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    • 2000
  • Langasite is a promising new piezoelectric material for SAW filter application. Little was known until recently about the methods needed to mechanically polish and chemically polish/etch this material. In this experiment, polishing, slurry chemistry and chemical wet etching for langasite is described. Conventional quartz and LN ($LiNbO_3$) polishing methods did not produce satisfactory polished surfaces, and polishing with a colloidal silica slurries has shown to be most effective. The optimum condition was investigated by changing the slurry chemistry. As the planarization effect is very important in SAW filter applications, the examination of the effective particle number effect and the particle size effect was carried out. Z-cut langasite surface which had been polished with the colloidal silica slurries was etched in a variety of etchants. Conventional quartz etchants destroyed the polished surface. Other etchants formed a thin film on the surfaces. In this experiment, the reaction between langasite and a few etching solution was analysed. And an appropriate selective etchant solution for analyzing the defects was synthesized.

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A STUDY ON THE EFFECT OF DENTIN BONDING AGENTS APPLIED OVER ENAMEL ABOUT THE BOND STRENGTH OF COMPOSITE RESIN (접착강화제가 치아경조직과의 접착강도 변화에 미치는 영향에 관한 연구)

  • Choi, Woong-Dae;Park, Sang-Jin
    • Restorative Dentistry and Endodontics
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    • v.20 no.1
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    • pp.1-16
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    • 1995
  • The purpose of this study was to investigate the effect of dentin bonding agents on the bond strength of composite resin restorations in case of applying the dentin bonding agents to acid etched enamel surfaces. Freshly extracted 364 bovine anterior teeth were selected as a adherents. 320 enamel specimens were divided into two groups(unetched group (1) and etched group (2) for testing the shear bond strength, 40 specimens were used for the hardness testing, and 4 specimens of rest were to observe the resin-tag formation into etched enamel surfaces. All surfaces of enamel specimens were polished with 320~1500 SiC paper under continuous running water. In Group (1), 100 enamel specimens were polished and unetched. 220 polished enamel specimens in Group (2) were etched with 37 % phosphoric acid solution for 60 seconds, washed with water for 20 seconds, and dried with a light air pressure for 60 seconds. Three kinds of dentin bonding agents(Gluma, Prisma, Scotchbond 2) were evaluated the effect on the bond strength to conditioned enamel surfaces. Shear bond strengths were measured on the three cases such as a coating of primer only, a coating of sealer only, and a sequential coating of primer and sealer to acid etched enamel surfaces were compared with the bond strengths measured by the coating of enamel bonding agent followed by the bonding of composite resin (Photo clearfil bright, Kuraray, Japan) to unetched and acid etched enamel surfaces. In addition, the hardness tested on the adhesive fractured surface between composite resin enamel as a mean of evaluation of a factor whether the mechanical bond strengths were affected and the penetration of dentin bonding agents into etched enamel surfaces was also observed. Bond strengths were measured using the method of shear bond strength by a universal testing machine (Instron-4467, USA), statistical test were applied to the results using a one way analysis variance(ANOVA), and hardness was measured by the Vicker's Hardness Tester(MHT-i, Matsuzawa, Japan) and the penetration of the resins were observed by the SEM (Hitachi, S-2300, Japan). The following conclusions were drawn; 1. Enamel bonding agent showed to affect the improvement of bond strength of composite resin to enamel surface both unetched and etched. 2. Dentin bonding agents could be resulted in increase of bond strength to unetched enamel surface, but there were no statistical significances. 3. Bond strengths to etched enamel surface were significantly decreased with a coating of dentin primer only. 4. Coating of sealer only and coating of primer and sealer noticed the similar bond strengths of composite resin to etched enamel using the enamel bonding agents. 5. The applying method proved to be more effective than the kinds of dentin bonding agents on the bond strength of composite resin to etched enamel than the kind of dentin. 6. Vicker's hardness numbers of dentin bonding agents were lower than that of composite resin, but the degree of penetration of dentin bonding agents into etched enamel surfaces was excellent.

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