• 한국콘텐츠학회논문지
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• 제15권9호
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• pp.384-394
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• 2015

본 연구에서는 원통형 지르코니아 코어에 다섯 종류의 지르코니아 비니어 세라믹을 축성하여 push-전단결합강도를 측정하고, 비니어 세라믹의 이축굽힘강도와 지르코니아 글라스 라이너 처리에 따른 전단결합강도 차이를 알아보고자 하였다. 지르코니아 비니어 세라믹은 piston-on-three-ball test로 이축굽힘강도를 측정하였고, 지르코니아 실린더 코어와 비니어 세라믹은 push-shear test로 결합강도를 측정하였으며, 결과값은 이원분산분석을 사용하여 분석하였다. 이축굽힘강도는 Cercon ceram kiss (CE)군에서 가장 높게 측정되었고 전단결합강도는 글라스 처리군과 Triceram(TR)군이 높게 측정 되었으며 Creation ZI(CR)군에서 가장 낮은 값이 측정 되었다. 실험군에서 지르코니아 라이너 처리군이 라이너 처리하지 않는 군보다 전단결합강도가 높게 나타났으며 통계적으로 유의한 차이를 보였다(P<0.05). 따라서 지르코니아 라이너 처리는 지르코니아와 비니어 세라믹의 결합강도를 향상시킬 수 있는 것으로 사료된다.

• The Journal of Advanced Prosthodontics
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• 제7권5호
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• pp.349-357
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• 2015

PURPOSE. The purpose of this study was to assess the impact of the core materials, thickness and fabrication methods of veneering porcelain on prosthesis fracture in the porcelain fused to metal and the porcelain veneered zirconia. MATERIALS AND METHODS. Forty nickel-chrome alloy cores and 40 zirconia cores were made. Half of each core group was 0.5 mm-in thickness and the other half was 1.0 mm-in thickness. Thus, there were four groups with 20 cores/group. Each group was divided into two subgroups with two different veneering methods (conventional powder/liquid layering technique and the heat-pressing technique). Tensile strength was measured using the biaxial flexural strength test based on the ISO standard 6872:2008 and Weibull analysis was conducted. Factors influencing fracture strength were analyzed through three-way ANOVA (${\alpha}{\leq}.05$) and the influence of core thickness and veneering method in each core materials was assessed using two-way ANOVA (${\alpha}{\leq}.05$). RESULTS. The biaxial flexural strength test showed that the fabrication method of veneering porcelain has the largest impact on the fracture strength followed by the core thickness and the core material. In the metal groups, both the core thickness and the fabrication method of the veneering porcelain significantly influenced on the fracture strength, while only the fabrication method affected the fracture strength in the zirconia groups. CONCLUSION. The fabrication method is more influential to the strength of a prosthesis compared to the core character determined by material and thickness of the core.

• 대한치과기공학회지
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• 제37권4호
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• pp.243-250
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• 2015

Purpose: The aim of this study was to investigate the shear bond strength between various commercial zirconia coping and veneering ceramic, and to observe the failure mode. Methods: For each zirconia block (iJAM Emerald, LUXEN Smile block, ICE Zirkon transluzent), 10 rectangular specimens were layered with Cercon ceram kiss, IPS e.max ceram, ICE Zirkon ceramic according to recommended by the manufacturer. The shear bond strength tests of the veneering porcelain to zirconia were carried out until fracture by a universal testing machine. After the shear bond tests, failure modes were characterized visually, under a stereomicroscope, such as adhesive, cohesive, or mixed. Data were analyzed with One-way ANOVA followed by Scheffe's tests. Results: The shear bond strength ($mean{\pm}SD$) of zirconia-veneer ceramic were JC group $13.9{\pm}3.6MPa$; JE group $17.7{\pm}2.4MPa$; JI group $15.1{\pm}2.5MPa$; LC group $9.5{\pm}1.5MPa$; LE group $16.2{\pm}2.3MPa$; LI group $12.6{\pm}0.8MPa$; ZC group $16.0{\pm}2.3MPa$; ZE group $18.5{\pm}3.4MPa$; and ZI group $15.3{\pm}3.2MPa$. The One-way ANOVA showed a significant difference between groups (p<0.05). The failure mode in most experimental groups was mixed failure, except for the LC group, which showed adhesive failure, and JE group, LE group and ZE group showed cohesive failure. Conclusion: For IPS e.max ceram, the shear bond strength value was highest for all kinds of zirconia blocks. For ICE Zirkon transluzent, the shear bond strength value was highest for all kinds of veneering ceramics. Most of experimental group interfaces revealed mixed failure mode.

• The Journal of Advanced Prosthodontics
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• 제8권5호
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• pp.339-344
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• 2016

PURPOSE. Pre-surface treatments of coping materials have been recommended to enhance the bonding to the veneering ceramic. Little is known on the effect on shear bond strength, particularly with new coping material. The aim of this study was to investigate the shear bond strength of veneering ceramic to three coping materials: i) metal alloy (MA), ii) zirconia oxide (ZO), and iii) lithium disilicate (LD) after various pre-surface treatments. MATERIALS AND METHODS. Thirty-two (n = 32) discs were prepared for each coping material. Four pre-surface treatments were prepared for each sub-group (n = 8); a) no treatment or control (C), b) sandblast (SB), c) acid etch (AE), and d) sandblast and acid etch (SBAE). Veneering ceramics were applied to all discs. Shear bond strength was measured with a universal testing machine. Data were analyzed with two-way ANOVA and Tukey's multiple comparisons tests. RESULTS. Mean shear bond strengths were obtained for MA ($19.00{\pm}6.39MPa$), ZO ($24.45{\pm}5.14MPa$) and LD ($13.62{\pm}5.12MPa$). There were statistically significant differences in types of coping material and various pre-surface treatments (P<.05). There was a significant correlation between coping materials and pre-surface treatment to the shear bond strength (P<.05). CONCLUSION. Shear bond strength of veneering ceramic to zirconia oxide was higher than metal alloy and lithium disilicate. The highest shear bond strengths were obtained in sandblast and acid etch treatment for zirconia oxide and lithium disilicate groups, and in acid etch treatment for metal alloy group.

• 대한치과기공학회지
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• 제38권3호
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• pp.135-142
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• 2016

Purpose: The aim of this research was to evaluate the influence of different surface treatments on the shear bond strength of zirconia ceramic to composite resin. Methods: Seventy two cylinder-shape (diameter: 5 mm; height: 12 mm) blocks of experimental industrially manufactured Y-TZP ceramic were abraded with $125{\mu}m\;Al_2O_3$ particles and randomly divided into 4 groups. All the materials were categorized as group Gc(control group - composite resin veneering on zirconia surface), Gr - composite resin veneering after surface treatment of Rocatec system (3M ESPE, Seefeld, Germany) group; Gz - composite resin veneering after surface treatment of Zirconia primer (Z-primer, Bisco, U.S.A) group; Gm - composite resin veneering after surface treatment of zirconia primer (Monobond plus, ivoclar vivadent AG, Liechtenstein) group. Two different zirconia primers and Rocatec system were used to zirconia cylinders (n=16) onto the zirconia surface. Zirconia specimens, polished and roughened, were pretreated and composite bilayer cylinders bonded using conventional adhesive techniques. Results: Shear bond strengths were analyzed using single-factor ANOVA(p<0.05). Bond strength values achieved after airbone particle abrasion and zirconia surface pre-treatments(p<0.05). Conclusion: Shear bond strength tests denmonstrated that zirconia primer is a viable method to improved bond strength between zirconia ceramic core and veneering composites.

• 대한치과보철학회지
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• 제38권3호
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• pp.328-335
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• 2000

Statement of the problem. Recently an innovative method of fabricating indirect restorations by gold electroforming has been developed. But the bond quality and strength of the gold coping to the porcelain is uncertain. Purpose of study. The purpose of this study is to analyze and evaluate the electroformed gold surface for mechanical bonding between the gold and the ceramic veneering. Methods/material. Electroformed disks were made using electroforming technique. And the surface of the electroformed coping was analyzed after sandblasting, heat-treatment, bonding agent application, opaque porcelain firing with scanning electron microscopy and energy dispersive x-ray analysis. Results. In the analysis with SEM, Sandblasting made the sharp edges and undercuts on the electroformed surface, and after bonding agent application, net-like structure were created on the electroformed surface. In the energy dispersive x-ray analysis it is confirmed that electroformed surface contains some impurities. Conclusion. With the use of sandblasting and bonding agent, electroformed surface seems to be enough to bond with veneering porcelain.

• 치위생과학회지
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• 제12권2호
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• pp.123-129
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• 2012

이 연구에서는 지르코니아 코어의 두께를 달리 제작하여 동일한 색조의 상부도재를 축성함에 있어 제작방법을 다르게 하여 두 상반된 시편을 각각 분광측색장치를 이용하여 CIE $L^*,a^*,b^*$ 색체계로 산출하여 객관적으로 색차를 비교, 분석하여 다음과 같은 결론을 얻었다. 1. 지르코니아 코어의 두께가 두꺼워 지고 상부도재의 두께가 얇아지면서 $L^*$ 값의 수치는 높아지며 $a^*,b^*$ 값은 낮아지는 경향을 띠었다. 상부도재 축성방법을 다르게 제작한 시편에서도 같은 결과를 보였다. 동일한 색조 시편에서 HP군은 PST군에 비해 $L^*$ 값의 수치는 낮게 측색되어 어두운 경향을 보였으며 $a^*,b^*$ 값도 낮은 수치를 보여 황색의 경향을 띠었다. 2. HP군, PST군 모두 동일한 색조에서 지르코니아 코어 두께와 상부도재 제작방법 간에 교호작용은 없었다(P=.083). 지르코니아 코어의 두께에 따라서는 통계적으로 유의한 차이는 존재하였으며(P=.001), 두께가 0.3 mm의 시편 A1, A2 색조에서 색차 값($E^*$)은 3.7 이상으로 나타났고, 그 이외 시편에서는 3.7 이하로 분석되어 임상가능 허용치로 나타났다. 이상의 결과로 볼 때 지르코니아를 이용한 전부 도재관 제작 시 같은 색조의 재료 일지라도 제작방식과 상부도재의 재료에 따라 색차 값이 존재하므로 이를 감안하여 보철물 제작에 사용해야 할 것으로 사료되며, 특히 코어의 두께가 얇은 보철물에서는 임상 허용치 이상의 색차 값을 보이므로 코어의 두께를 좀 더 추가하여 설계한 보철물이 바람직하다고 생각된다.

• 구강회복응용과학지
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• 제26권3호
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• pp.253-264
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• 2010

최근 개발된 Yttrium-stabilized-tetragonal-zirconia-polycrystal(Y-TZP ceramic)은 생체 친화적이며 높은 굴곡 강도, 파절 저항성, 파괴 인성을 지니고 CAD-CAM을 통해 milling이 가능하여 많은 치과 영역에서 사용되고 있다. 구치부 zirconia framework을 사용하는 고정성 수복물의 경우에는 상부 장석 도재의 상대적으로 높은 빈도의 파절을 보이고 있다. 복합레진은 취성이 적고 법랑질 보다 마모도가 낮으며 수리가 용이하다. 높은 교합압 부위에서 전장용 복합레진을 사용한 임플란트 수복은 기능적인 장점을 지니며 흥미롭게 여겨지고 있다. 이번 연구의 목적은 Y-TZP ceramic에 몇 가지 표면 처리를 시행하여 전장용 복합레진을 적용 시켰을 때 도재 전장시과 비교하여 임상적 활용을 위한 유용한 전단결합강도를 지니는지를 알고자 함이다.

• The Journal of Advanced Prosthodontics
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• 제7권1호
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• pp.69-75
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• 2015

PURPOSE. To compare the shear bond strength of various veneering materials to grade II commercially pure titanium (CP-Ti). MATERIALS AND METHODS. Thirty specimens of CP-Ti disc with 9 mm diameter and 10 mm height were divided into three experimental groups. Each group was bonded to heat-polymerized acrylic resin (Lucitone 199), porcelain (Triceram), and indirect composite (Sinfony) with 7 mm diameter and 2 mm height. For the control group (n=10), Lucitone 199 were applied on type IV gold alloy castings. All samples were thermocycled for 5000 cycles in $5-55^{\circ}C$ water. The maximum shear bond strength (MPa) was measured with a Universal Testing Machine. After the shear bond strength test, the failure mode was assessed with an optic microscope and a scanning electron microscope. Statistical analysis was carried out with a Kruskal-Wallis Test and Mann-Whitney Test. RESULTS. The mean shear bond strength and standard deviations for experimental groups were as follows: Ti-Lucitone 199 ($12.11{\pm}4.44$ MPa); Ti-Triceram ($11.09{\pm}1.66$ MPa); Ti-Sinfony ($4.32{\pm}0.64$ MPa). All of these experimental groups showed lower shear bond strength than the control group ($16.14{\pm}1.89$ MPa). However, there was no statistically significant difference between the Ti-Lucitone 199 group and the control group, and the Ti-Lucitone 199 group and the Ti-Triceram group. Most of the failure patterns in all experimental groups were adhesive failures. CONCLUSION. The shear bond strength of veneering materials such as heat-polymerized acrylic resin, porcelain, and indirect composite to CP-Ti was compatible to that of heatpolymerized acrylic resin to cast gold alloy.

• The Journal of Advanced Prosthodontics
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• 제3권4호
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• pp.196-203
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• 2011

PURPOSE. This study evaluated marginal fit of glass infiltrated alumina cores fabricated using two techniques and their marginal stability after firing cycles of veneering porcelain. MATERIALS AND METHODS. Fifteen standardized all-ceramic crowns were fabricated on a metal die using each technique: slip cast technique of VITA In-Ceram sprint Alumina (Group A as control) and plastic foil matrix technique of Turkom-Cera fused alumina core system (Group B). Copings were compared between groups and within groups at coping stage and after firing each layer of veneering porcelain. A device was used to standardize seating of copings on the metal die and positioning of the specimens under the microscope after each stage of fabrication. The specimens were not cemented and marginal gap was measured using an image analyzing software (Imagepro Express) on the photographs captured under an optical microscope. Two tailed unpaired 't test' was used to compare marginal gaps in two groups and one way ANOVA was used to analyze marginal distortion within each group at 95% confidence interval. RESULTS. The marginal gap was smaller at the coping stage in group B ($60+30{\mu}M$) than group A ($81+21{\mu}M$) with statistical significance. After firing of veneering porcelain the difference was insignificant. At the final stage, both groups exhibited lower mean marginal gaps than at the initial coping stage with the difference of $11.75{\mu}M$ for group A and $11.94{\mu}M$ for group B, but it was statistically insignificant due to high value of standard deviation. CONCLUSION. Within the limitations of this study, it was concluded that both techniques produced copings with comparable and acceptable marginal fit and marginal stability on firing veneering porcelain.