• 대한치과기공학회지
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• 제30권1호
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• pp.65-71
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• 2008

The use of titanium in the field of dentistry has increased, due to their excellent biocompatibility, appropriate mechanical properties, corrosion-resistance and low price. However, many difficulties with the use of titanium for metal-ceramic crowns remain to be solved. The objective of this study was to evaluate the influence of surface modifications on the bonding characteristics of specific titanium porcelain bonded to cast titanium. The surfaces of Titanium were prepared with 4 test groups, i) sandblasted with particles of different size, ii) sandblasted after treated oxidization and oxidized after sandblast. We observed the bond strength and node aspect of titanium and ceramic, and respect to the methods of modifying surface of titanium by the test of mean roughness of surface, Scanning Electron Microscope, and 3-point flexural bend test. The results show that, 1. The specimens, which treated oxidization after process of sandblast with particles of 50um size, were the better for the bond strength in comparison with other specimen. 2. The specimen with process of sandblasting after oxidization treatment were the better for stability of the bond strength. 3. The wettability of titanium surface affect the bond strength.

• 대한치과기공학회지
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• 제33권1호
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• pp.37-45
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• 2011

Purpose: Heat pressed ceramics, used for all ceramic restorations, have the additional advantage of being technically less change through using of the lost-wax technique. Conceptually, combining the ceramic with the clinically proven reinforcing ability of a metal framework would be advantageous; however, cause of mismatching of fusion between ceramics and metal frameworks which from differences of casting temperature and coefficient of thermal expansion, pressed ceramics could not be used with a metal framework. The purpose of this study was to compare shear bond strength of press-to metal ceramic to porcelain fused non precious metal and feldspatic porcelain fused non precious metal. Methods: The 30 metal specimens were casted in a porcelain fused non precious metal nickel-chromium alloy. They were divided into 3 groups by surface treatment and applied ceramic: $125{\mu}m$ aluminium oxide sandblasting and veneered feldspatic porcelain (group FP), $125{\mu}m$ aluminium oxide sandblasting and had press-to-metal ceramic applied (group PC), porcelain bonder (gold bonder) fused on surface of metal specimens and had press-to-metal ceramic applied (group PCG). In each group 10 metal specimens were used. The press-to-metal ceramic applied 20 specimens had ash-free wax pattern applied, the metal-wax complexes invested, and were pressed with heat press ceramic. All specimens were subjected to shear bond strength test at a crosshead speed of 1.0 mm/min. Results: The results of measured in Mean SD and data were analyzed by one-way AVOVA (p= .05) and Tukey HSD test (p= .05).: group FP $16.090{\pm}1.841$ MPa, group PC $12.620{\pm}1.8256$ MPa, group PCG $10.920{\pm}0.9283$, significant differences between all groups (p < .05). Significant differences were found in each between group FP and group PC, group FP and group PCG (p < .05). Conclusion: The shear bond strength of press-to-metal ceramic to porcelain fused non precious metal was described higher in unused gold bonder group than used gold bonder groups.

• 대한의생명과학회지
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• 제14권2호
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• pp.105-113
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• 2008

The objective of this study was to evaluate the influence of surface modifications on the bonding characteristics and cytotoxicity of specific titanium porcelain bonded to milling titanium and cast titanium. Milling titanium and cast titanium samples were divided into 8 test groups. These groups are as follow: i) sandblasted with particles of different size of $220{\mu}m\;and\;50{\mu}m$, ii) different sequences of sandblasting treatment and etching treatment, iii) etched with different etching solutions, and iv) preheated or not. The surface characteristics of specimens were characterized by the test of mean roughness of surface and SEM. The bond strength of titanium-ceramic systems was measured by using three-point bending test and SEM. The results show that the mean roughness of surface of sample sandblasted with $220{\mu}m$ aluminum oxide increased and bond strength were higher than sample sandblasted with $50{\mu}m$ aluminum oxide. The mean roughness of surface decreased, but the bond strength increased when the samples sandblasted with $220{\mu}m$ aluminum oxide were preheated. The sample sandblasted with $220{\mu}m$ aluminum oxide after oxidized with occupational corrosive agent I (50% NaOH, 10% $CuSO_4{\cdot}5H_2O$) and II (35% $HNO_3$, 5% HF) showed higher bond strength than sample oxidized with 30% $HNO_3$ after sandblasted with $220{\mu}m$ aluminum oxide. Group NaCuNF220SP (milling Ti: 35.3985 MPa, casting Ti: 37.2306 MPa) which was treated with occupational corrosive agent I (50% NaOH, 10% $CuSO_4{\cdot}5H_2O$) and II (35% $HNO_3$, 5% HF), followed by sandblasting with $220{\mu}m$ aluminum oxide and preheating at $750^{\circ}C$ for 1 hour showed the highest bond strength and significant differences (P<0.05). The method for modifying surface of titanium showed excellent stability of cells.

• 대한치과기공학회지
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• 제38권2호
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• pp.69-77
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• 2016

Purpose: This study was to evaluate the shear bond strength of ceramic fused to Ni-Cr alloy(Alophaloy) by heat treatment. Methods: The specimens were divided into 5 groups according to heat treatment conditions prior to porcelain application. Eighteen specimens from each group were subjected to the shear load a universal testing machine using a 0.1mm/min cross-head speed and two specimens from each group were observed with SEM and EDX line profile. Results: The observation of the oxide film on the metal surface by SEM photograph showed a coarsening with an increasing degassing hold time. The diffusion of metal oxide was observed farther from the opaque layer in the heat treated specimen than no heat treated specimen. The shear bond strength measured highest to A5(55.23MPa) in the 10min holding group and measured lowest from A1(24.38MPa) in the no heat treated group, and there was a significant difference(p<0.05). Conclusion: The shear bond strength of Ni-Cr alloy improved in the heat treatment compared to the no heat treatment specimen.

• 구강회복응용과학지
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• 제24권1호
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• pp.113-127
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• 2008

이 연구의 목적은 지르코니아 도재 표면의 전단 결합 강도에서 $ZirLiner^{(R)}$와 블라스팅 처리의 적용 효과를 평가하기 위한 것이다. 60개의 무색의 지르코니아 판과 30개의 색이 있는 지르코니아 판이 규격화되고 연마, 글래스블라스팅, 알루미나블라스팅, 그리고 zirliner 같은 블라스팅 처리를 적용시키는 것에 따라 10개씩 9개의 그룹으로 나누어졌다. 시편을 고정대에 위치하고 만능시험기로 전단력을 측정하였다. 파절된 견본의 파절 표면은 SEM으로 검사되었다. 각 군별 시편을 통계처리하여 그 결과를 비교하였다.

• 대한치과보철학회지
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• 제34권3호
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• pp.533-538
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• 1996

도재 소부용 비귀금속합금의 표면처리가 금속과 도재간의 전단결합강도에 어떠한 영향을 미치는지 알아보기 위하여, 비귀금속 합금의 표면에 어떠한 처리도 하지 않는 대조군과 샌드브라스팅한 실험군, 스퍼트 에칭한 실험군, 그리고 샌드브라스팅후 스퍼트 에칭한 실험군으로 나눈 후에 각각의 시편에 통상적인 방법으로 도재를 소성한 후 인스트론 만능 시험기를 사용하여 전단결합강도를 측정하여 다음과 같은 결론을 얻었다. 1. 샌드브라스팅후 스퍼트 에칭한 실험군과 샌드브라스팅한 군은 대조군에 대해 높은 값을 나타내었다(P<0.05). 2. 스퍼트 에칭한 실험군은 대조군에 대해 차이가 없었다(P>0.05).

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.43-46
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• 1997

The interfacial bond strength and microstructural analysis of pre-heat treated porcelain-fused-metal (PFM) were investigated using a mechanical three-point bending tester and scanning electron microscope(SEM). Four kinds of heat treated samples were prepared as follows; A: heating $1200^{\circ}F\rightarrow1600^{\circ}F$, holding 1min, reheating $\rightarrow1850^{\circ}F$, hold 3min under vacuum, B: heating $1200^{\circ}F\rightarrow1600^{\circ}F$ holding 1min, reheating $\rightarrow1850^{\circ}F$ under vacuum condition, C: heating $1200^{\circ}F\rightarrow1600^{\circ}F$, holding 1min, reheating $\rightarrow1850^{\circ}F$, holding 3min in the air, repeat same heat treatment process under vacuum condition, D: heating $1200^{\circ}F\rightarrow1600^{\circ}F$, holding 1min, reheating $\rightarrow1850^{\circ}F$, holding 1min in the air. The three-point bending test results shows that the interfacial bond strength of specimen B and C were higher than that of A and B. The SEM study reveals that Specimen C shows the highest surface density.

• 대한치과기공학회지
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• 제19권1호
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• pp.37-42
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• 1997

The interfacial bond strengh and microstructural analysis of pre-heat treated porcelain-fusedmetal(PFM) were investigated using a mechanical three-point bending tester and scanning electron microscope(SEM). Four kinds of heat treated samples were prepared as follows ; A: Heating $1200^{\circ}F{\to}1600^{\circ}F$, holding 1min, reheating ${\to}1850^{\circ}F$, hold 3min under vacuum, B: heating $1200^{\circ}F{\to}1600^{\circ}F$, holding 1min, reheating${\to}1850^{\circ}F$ under vacuum conditon, C: heating $1200^{\circ}F{\to}1600^{\circ}F$, holding 1min, reheating${\to}1850^{\circ}F$, holding 3min in the air, repeat same heat treatment process under vacuum condition, D: heating $1200^{\circ}F{\to}1600^{\circ}F$, holding 1min, reheating${\to}1850^{\circ}F$, holding 1min in the air. The three-point bening test result shows that the interfacial bond strength of specimen B and C were higher than that of A and D. The SEM study indicate that Specimen C shows the highest surface density.

• 대한치과보철학회지
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• 제29권2호
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• pp.195-209
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• 1991

When the porcelain fused to metal restorations were fractured at the metal interface, various techniques and materials for intraoral porcelain repair have been suggested. The purpose of this study was to investigate the effect of metal surface treatment method and water storage on the shear bond strength of four porcelain repair systems. : Clearfil(Kuraray), All-bond(Bisco), Superbond C & B(Sun Medical), Panavia OP(Kuraray). After the metal surfaces of the specimens were sandblasted by aluminum oxide or roughened by diamond point, they were stored in double deionized water(24 Hr., $37^{\circ}C$) and thermocycling was performed(24 Hr., 1024 cycles), and again half of specimes were stored in water bath(2 Months, $37^{\circ}C$). Mean shear bond strength and mode of failure were recorded. The results of this study were obtained as follows : 1. Differences were observed between the sandblasted and diamond - treated specimens in Clearfil, All-bond, and Superbond. No statistically significant differences were observed in Panavia. 2. The 2-month storage time significantly affected the bond strength of All-bond and Superbond. No statistically significant differences were observed in Clearfil and Panavia. 3. The failures were observed at the interface between opaque resin and the metal in Clearfil and All-bond. 4. The failures were observed at the interface between opaque resin and veneered resin in Panavia. The failures were observed at the interface between opaque resin and veneered resin in Superbond, but 40% of them were fractured at the interface between the metal and opaque resin after 2-month storage time.

• 대한치과보철학회지
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• 제29권3호
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• pp.33-41
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• 1991

Cermic has been widely used because of its excellent esthetics and strength. The recently introduced castable ceramic system is regarded as the more esthetic and biocompatible restorative material. The purpose of this study was to compare the shear bond strength of Dicer & G-Cera porcelain laminate veneer according to the type of cement and surface treatment and to observe the surface of bonding failure with SEM. Total forty disks(3.5mm $diam.\times2.0mm$ thickness) were prepared. Forty extracted human maxillary central incisor teeth were stored in saline solution. Ten teeth were bonded to Dicer specimen with Dicer ZPC cement and ten teeth were bonded with Dicer resin cement. Ten silicoated G-Cera specimen and ten non-silicoated G-Cera specimen were bonded to teeth with G-Cera resin cement. Bonded units were mounted in a plastic tube with hard stone and stored in a humidor at $37^{\circ}C$ for 24 hours. Shear bond strength was measured by Instron Universal Testing Machine (Model 1125) and all the specimen were observed with SEM(JEOL, JSM-T2000)and modes of failure were recorded. The obtained results were as follows: 1. The mean shear bond strength of Dicer bonded with Dicer resin cement was 11.62 MPa and that bonded with Dicor ZPC cement was 0.88 MPa : Shear bond strength of Dicer bonded with Dicer resin cement was significantly increased(P<0.05). 2. The mean shear bond strength of silicoated G-Cera was 13.10 MPa and that of non silicoated G-Cera was 10.93 MPa : Shear bond strength of silicoated G-Cera was not significantly increased (P>0.05). 3. Shear bond strength of Dicer and G-Cera porcelain laminate veneer was not significantly different (P>0.05). 4. In observation of bond failure with SEM, Dicer bonded with Dicer ZPC cement exhibited adhesive failure. Dicer bonded with Dicer resin cement and silicoated and non silicoated G-Cera exhibited cohesive failure.