TiN 코팅된 Ti-Nb 합금의 표면 특성

고영무,최한철 대한치과재료학회 2004 대한치과재료학회지 Vol.31 No.3

치과용 임플란트 재료는 임플란트 고정체와 주위의 골조직 사이에서 아주 좋은 골융합을 해야한다. TiN 코팅된 치과용 임플란트 재료의 Ti-Nb합금의 부식특성을 알아보기 위하여 Ti에 3wt%, 20wt% 그리고 40wt%까지 진공로를 이용하여 Nb를 용해한 후에 균질화하였다. 시편은 EB-PVD법으로 수 ㎛ 두께로 각각 TiN을 코팅하였다. 미세조직과 상의 분석은 SEM을 이용하여 관찰하였다. Ti합금의 가공도는 인장강도 시험기를 이용하였으며 부식거동은 0.9% NaCl 전해액에서 potentiostat를 사용하여 조사하였고 부식표면은 SEM과 XPS을 이용하여 관찰하였다. 3 wt%와 20 wt% Nb를 포함한 Ti에서 Ti4Nb의 2차의 상은 α+β구역에서 나타났으며 Ti-40Nb 합금의 경우에서는 미세구조가 조대한 β상이고 Ti4Nb와 같은 석출물이 나타났다. 부식거동을 조사한 결과 α+β type 합금의 전류밀도는 낮게 나타났으며 따라서 α+β type 합금은 좋은 부식저항을 나타내었다. TiN으로 코팅한 Ti 합금의 부식전위, 피막 파괴전위, 재부동태화 전위는 Nb의 함유량에 따라서 증가하였지만 활성태 구역에서 전류밀도와 부동태영역에서 전류 밀도는 감소하였다. TiN으로 코팅한 Ti-40Nb 합금은 TiN으로 코팅되지 않은 시편보다 우수한 부식저항성을 갖는 것으로 나타났다.

치과 교정용 스테인리스 강 선재의 신선 가공법이 내식성에 미치는 영향

고영무 대한치과재료학회 2003 대한치과재료학회지 Vol.30 No.1

스테인리스강 소결체를 이용한 치과용 임플란트 개발 (Ⅱ) : 치과용 소결체의 제작과 독성시험을 중심으로 Toxicity of Sintered Stainless Steel

고영무,최한철,박주철 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.4

The first factor to decide the success of dental implantaion is sufficient osseointegration between implant fixture and its surrounding bone tissue. Thus many studies about this have been under actively. In this study, in order to fabricate sintered dental implant, the effects of Cu content on biocompatibility, call toxicity, osseointegration of electroless Cu-p;ated and sintered stainless steel implant were investigated using various characteristics. Stainless steel compacts containing 2, 4, and 10 wt%Cu were prepared by electroless Cu-plating method which results in the increased homogenizationg in alloying powder. Using the culture of human gingival fibroblasts, cell growth and viability were analysed on 2th, 4th and 6th experimental days. The succinate dehydrogenase (SDH) activity was examined by Millipore filter method and Agar overlay method was ultilized to detect the acute cytotoxicity of implant materials. Sinterd stainless steel containig 2wt% and 4wt% Cu showed good mechanical strength and has a good porosity for dental implant materials. Also it showed a good cell growth without toxicity. In both of #62 and #64 specimens, the total number of gingival fibroblasts was gradually increased for experimental periods and their surveval rates were similar with those of negative control group after 1 and 3 days, and higher than those after 5 days. In the Millipore filter and Agar overlay tests, there was no cytotoxicities in both #62 and #64 specimens. Results suggest that the best sintered dental implant material is 4 wt% Cu sintered stainless steels with a mechanical strength and biocompatibility.

스테인리스강 소결체를 이용한 치과용 임플란트 개발(Ⅰ) -치과용 소결체의 제작과 물성을 중심으로

고영무 대한치과재료학회 2003 대한치과재료학회지 Vol.30 No.3

2 급 와동 수복시 사용방법에 따른 복합 레진 인레이의 변연누출에 관한 실험적 연구

고영무,박경준,김경남,계기성 朝鮮大學校 口腔生物學硏究所 1993 口腔生物學硏究 Vol.17 No.1

치과용 임플란트의 표면처리를 위한 나노튜브형성

고영무,최한철 대한치과의사협회 2007 대한치과의사협회지 Vol.45 No.11

최과 교정용 스테인리스 강 선재의 신선 가공법이 내식성에 미치는 영향

고영무,모웅남,최한철 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.1

The dental orthodontic wire requires good mechanical properties, such as elastic strength, combined with a high resistance to corrosion. For increasing elastic strength and delaying onset of stress corrosion cracking, drawing methods(one-step and two-step drawing) have been used in this study to extend service life of metal components, However, there is no information on the electrochemical corrosion behavior of drawn wires for orthodontics. To increase elastic strength, good corrosion resistance, and biocompatibility, the electrochemical characteristics of drawn wire have been researched by field emission scanning microscope and potentiodynamic method in 0.9% NaCl solution. The one-step drawn wire showed the formation of rough surface. The hardness and tensile strength of two-step drawn wire increased. Electrochemical measurements showed that, in the case of two-step drawn wire, the corrosion resistance and pitting potential increased compared with two-step drawn wire due to the drawing induced small surface roughness, such as scratch, whereas passivation and active current density decreased as the reduction in area for drawing increased.

키토산을 첨가한 콤포짓트 레진의 기계적 성질과 항균성에 관한 연구

고영무,국중기,배태성,유소영,김미광,오승한,배지명 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.4

The purpose of this study is to evaluate the mechanical and anti-microbial properties of newly prepared chitosan H for human gingival fibroblast. Compressive strength, diametral tensile strength and tensile strength of specimens of composite, with or without chitosan H incorporated, were measured. Using a SEM (S-4700, Hitach, Japan), pictures of microbes were taken and adherent capability of microbes to the surface of resin composite was investigated. The MIC of newly prepared chitosan H for S. mutans was 500㎍/㎖. The cytotoxicity of newly prepared chitosan H for human gingival fibroblast was not showed. In terms of compressive strength, diametral tensile strength and tensile strength, composite resin containing 7㎎/㎖ chitosan H had highter value than control group. The adherent capability of microbes decreased as the amount of chitosan H increased in the test specimens compared to the control group but there was no statistical significance for S. mutans. In conclusion, resin composite with chitosan H incorporated did not show any statistically significant difference for mechanical properties but it showed a significant antimicrobial effect against Candida albicans.

전자빔 진공증착을 이용한 치과용 임플란트재의 표면 전처리법에 따른 HA 코딩효과

고영무,최한철,최낙찬 大韓齒科器材學會 2002 대한치과재료학회지 Vol.29 No.4

The dental implant materials require good mechanical properties, such as fatigue strength, combined with a high resistance to corrosion. For increasing fatigue resistance and delaying onset of stress corrosion cracking, shot-peening has been used for over 50 years to extend service life of metal components, However, there is no information on the electrochemical behavior of shot-peened and hydroxyapatite(HA) coated Ti-6Al-4V alloys. To increase fatigue strength, good corrosion resistance, and biocompatibility, the electrochemical characteristics of Ti/TiN/HA coated and shot-peened Ti-6Al-4V alloys by EB-PVD have been researched by various electrochemical method in 0.9%NaCl The coated layer and surface showed the formation of dense and uniform surface in the case of TiN/HA and Ti/TiN/HA film coated samples. The hardness of shot-peened Ti-6Al-4V alloys(SPA) increased as SP treatment time increased. Electrochemical measurements showed that, in the case of shot-peened Ti-6Al-4V alloys, the corrosion and pitting potential increased due to the SP induced removal of defects, such as inclusion, scratch, and pore on the surface, whereas passivation and active current density decreased as the SP time increased. For the HA coated samples, pitting and repassivation potential increased in the order of Ti/TiN/Ha > TiN/HA > Ti/HA > HA coated SPA. Results suggest that the best pitting corrosion behavior is shown by Ti/TiN/HA coated SPA with a fatigue strength and biocompatibility.

전해액의 종류에 따른 치과용 금합금의 전기화학적 부식 거동

고영무,최성욱 대한치과기재학회 2001 대한치과재료학회지 Vol.28 No.1

The effect of different electrolytes on the results from potentiodynamic polarization corrosion testing was studied for 3 different dental gold alloys. The obtained results were as follows. 1.From the potentiodynamic curves the corrosion behavior of natural saliva was similar to that of Darvell's and Hay & Hartles' artificial saliva solution. 2.Fusayama's and Tani & Zucchi's artificial saliva solutions were more corrosive than natural saliva, Darvell's and Hay & Hartles' artificial saliva solution. 3.The corrosion behaviors of Fusayama's and Tani & Zucchi's artificial solutions were very similar in case of Cast-1 and Cast-3. 4.3 kinds of all alloys showed that the amount of gold released was highest in Fusayama's artificial saliva solution. In conclusion, the corrosion behavior of natural saliva was similar to Darvell's and Hay & Hartles' artificial saliva and Fusayama's artificial saliva solution was the more corrosive than any other solutions. But the effect of different electrolytes the corrosion behavior of high gold alloys was not different highly.