• Journal of Digital Convergence
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• v.19 no.3
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• pp.245-251
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• 2021

This study was to investigate the effect of the new surface treatment method of zirconia on the shear bond strength with resin cement. The zirconia specimens were classified according to the surface treatment. CON: non-treatment, HF: 10 minutes exposure to 9% HF, ZS15: Apply 15% ZrO2 slurry, ZS30: Apply 30% ZrO2 slurry, ZS50: Apply 50% ZrO2 slurry. The resin cement was layered on the surface treated zirconia, and the shear bond strength between the zirconia and the resin cement was measured after thermo-cycling. The statistical methods for shear bond strength were Kruskal-Wallis test, Mann-Whitney U test, and Bonferroni correction(α=.05/10=.005). ZS15, ZS30, and ZS50 groups treated with zirconia slurry showed higher shear bond strength than CON and HF groups(p<.05/10=.005). Within the limits of this study, the surface treatment using zirconia slurry increased the shear bond strength with resin cement. The new surface treatment method complements and improves the limitations of the adhesion of zirconia, so that various clinical applications of zirconia can be expected.

• Clean Technology
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• v.20 no.2
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• pp.130-135
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• 2014

It is investigated that the surface properties of mercaptopyruvic-acid layer formed on gold surfaces may make an effect on the distribution of either gold particle adsorbed to the zirconia surface or vice versa. For the investigation, the atomic force microscope was used to measure the surface forces between the surfaces as a function of the salt concentration and pH value. The forces were quantitatively analyzed with the derjaguin-landau-verwey-overbeek (DLVO) theory to estimate the electrostatic properties, potential and charge density, of the surfaces for each condition of salt concentration and pH value. The estimatedvalue dependence on the salt concentration was explained with the law of mass action, and the pH dependence was interpreted with the ionizable groups on the surface. The salt concentration dependence of the surface properties, found from the measurement at pH 4 and 8, was predictable from the law. It was found that the mercaptopyruvic-acid layer had higher values for the surface charge densities and potentials than the zirconia surfaces at pH 4 and 8, which may be attributed to the ionizedfunctional-groups of the mercaptopyruvic-acid layer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4329-4335
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• 2014

This study examined the effects of the shear bond strength when the surface condition of the metal and zirconia, each being the lower structures, was different when determining the bond strength (metal group) of the metal lower structure with upper ceramics, and the shear bond strength (zirconia group) of zirconia lower structure with the upper ceramics in prosthetic appliances of metal-ceramic crown and zirconia-ceramic crowns. The metal groups were divided into a total of four groups: the group with no condition on the metal surface(NM), the group with sand-blasting(SM), the group with applied opaque ceramics(OM), and the group with applied opaque ceramics and sand-blasting(SOM). The zirconia groups were also separated into four groups: the group with no condition(NZ), the group with sand-blasting(SZ), the group treated with ZirLiner on the zirconia surface(LZ), and the group applied with ZirLiner along and sand-blasting(SLZ). To examine the effects on the shear bond strength according to the surface condition of each of the four metal and zirconia groups, SPSS was used to conduct one-way ANOVA. For metal-ceramic crowns, it would be best to apply opaque ceramics after sand-blasting on the surface of the metal, the lower structure. For zirconia-ceramic crowns, it is recommended to apply the ZirLiner after sand-blasting on the surface of zirconia, the lower structure.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.49-56
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• 2011

Purpose: The aim of this study was to evaluate the effect of mechanical, chemical surface treatments on the zirconia-to-resin cement shear bond strength (SBS). Materials and methods: Eighty zirconia discs (Lava, 3M ESPE) and eighty zirconia/alumina composite (Zirace, Acucera) were embedded in an epoxy resin base. Zirconia discs were randomly divided in to four treatment groups(10 for each manufacturer): $50\;{\mu}m$ $Al_2O_3$ sandblasting (S50), $110\;{\mu}m$ $Al_2O_3$ sandblasting (S110), $50\;{\mu}m$ $Al_2O_3$ and primer (Z-Prime Plus, Bisco Inc) (S50z) and $110\;{\mu}m$ $Al_2O_3$ and primer (Z-Prime Plus) (S110z). Two resin-based luting cements (Calibra, Panavia F) were used to build 2 mm diameter cylinders onto the zirconia. After 24 h of storage in water, SBS testing was evaluate using a universal testing machine. Bond strength data were analyzed with one-way ANOVA, two-way ANOVA test and post hoc comparison was done using Tukey test (${\alpha}$ = .05). Results: Groups using primer showed the high shear bond strength. The groups that did not use primer presented lower shear bond strengths. Conclusion: The use of primer (Z-Prime Plus, Bisco) had significantly higher shear bond strengths.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.2
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• pp.73-81
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• 2013

Purpose: The purpose of this study was to evaluate the effect of surface treatment on the shear bond strength of zirconia ceramic to 3 resin cements. Materials and methods: A total of 143 disk-shaped Zirconia blocks (HASS Co., Gangneung, Korea) were randomly divided into three treatment groups: (1) only 50 ${\mu}m$ $Al_2O_3$ sandblasting, (2) 50 ${\mu}m$ $Al_2O_3$ sandblast and zircona liner, (3) 50 ${\mu}m$ $Al_2O_3$ sandblasting and Rocatec (3M ESPE, Seefeld, Germany). Bistite II (Tokuyama Dental Co., Japan), Panavia F (Kuraray Medical, Japan), and Superbond C&B (Sun Medical, Japan) were used to cement onto the zirconia. After 24h of storage in distilled water, shear bond strength was evaluated. High value group was re-tested after thermocycling at 5,000 cycles(5-$55^{\circ}C$). Shear bond strength data were analyzed with one-way ANOVA, two-way ANOVA test and Post Hoc Test (${\alpha}$=.05). Shear bond strength data before and after thermocycling were analyzed with Independent sample T test (${\alpha}$=.05). Results: Super-bond C&B treated with Rocatec showed the most high shear bond strength. Super-bond C&B groups resulted in significantly higher than other cement groups (P<.05). Rocatec groups resulted in significantly higher than other surface treatment groups (P<.05). Shear bond strength has increased in Panavia F treated with Zirconia liner (P<.05). After thermocycling, shear bond strength was increased in Super-bond C&B treated with Rocatec but decreased in other groups (P<.05). Conclusion: Super-bond C&B cement resulted the highest shear bond strength and Rocatec system enhanced the shear bond strength. After thermocycling, shear bond strength has decreased in most resin cements except Super-bond C&B treated with Rocatec.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.4
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• pp.354-363
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• 2016

Purpose: The aim of this study was to investigate whether the application of nano-structured alumina coating to the surface of Y-TZP could enhance the bond strength with resin cement. Materials and methods: A total of 80 zirconia plates were prepared and divided into four groups. : 1) airborne particle abrasion treatment (A) : 2) Rocatec treatment after airborne particle abrasion (R) : 3) nano-structured alumina coating treatment after polishing (PC) and 4) nano-structured alumina coating after airborne particle abrasion (AC). Alumina coating was formed by the hydrolysis of aluminium nitride (AlN) powder and heat treatment at $900^{\circ}C$. Coating patterns were observed with FE-SEM. Resin block was bonded to treated zirconia ceramics using resin cement. The shear bond strengths were measured before and after thermocycling. Results: The FE-SEM images show a dense and uniform nano-structured alumina coating structure, which enhances shear bond strength by increasing micro mechanical interlocking to resin cement. PC and AC groups showed higher shear bond strengths than A and R groups before and after thermocycling. A and R groups displayed significant drops in shear bond strength after thermocycling. However, PC and AC groups did not show any meaningful decreases in shear bond strength after thermocycling. Conclusion: Treatment of Y-TZP ceramics with nano-structured alumina coating could significantly increase their shear bond strength.

• Journal of the Korean institute of surface engineering
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• v.29 no.3
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• pp.176-185
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• 1996

플라즈마 용사된 열벽코팅의 수명을 평가하기 위하여 여러가지 양의 CeO$_2$(16,18,20,22,24 그리고 26 wt.% CeO$_2$)를 포함하는 지르코니아 코팅에 대한 상분석이 행하여 졌다. 플라즈마 용사된 후 16 및 18 wt.% CeO$_2$를 포함하는 지르코니아 코팅에서는 비평형 tetragonal 상 만이 생성되었으나 20-26 wt.% CeO$_2$를 포함하는 지르코니아 코팅에서는 비평형 tetragonal 및 cubic 상의 혼합상이 관찰되었다. 열순환 산화시험 동안에는 비평형 tetragonal 및 cubic 상은 평형 tetragonal 및 cubic 상으로 변태하였다. 평형 tetragonal 상의 일부는 열순환 산화시험의 냉각과정 중에 monoclinic 상으로 변태하였다. 그리고 16 wt.% CeO$_2$를 포함하는 지르코니아 코팅은 다른 조성의 지르코니아 코팅보다 열순환 산화시험 동안 더 많은 monoclinic 상이 생성되었으며 세라믹 코팅 수명이 짧았다.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.3
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• pp.319-326
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• 2012

For many years, ceramics have been used in fixed prosthodontics for achieving optimal esthetics. but, they have another use as well. Many studies today show ceramics can be used for biomaterials. In the beginning researchers made a start in the study of aluminium oxide and sapphire for biomaterial. The appearance of Zirconia began a new phase of research. Zirconia was introduced into implantology as an alternative to titanium, because of its white color, good mechanical properties and superior biocompatibility. But it is not easy to surface treatment in comparison with titanium. To overcome the limitation, interconnected porous bodies of zirconia were fabricated by sintering technique. And the technique of coating was developed. Therefore, some zirconia implants are currently available. It is thought that Research of biomaterials as a variety of puposes for the use of zirconia is looking very promising. The purpose of this paper reviews are to evaluation of zirconia as biomaterials.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.151-157
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• 2016

The purpose of this study was to compare of marginal fitness of zirconia copings according to impression techniques and zirconia blocks. For the conventional impression, two types of rubber impression materials were used and digital impression was made by using an intraoral scanner. Zirconia copings were manufactured from three types of blocks. With each of ten zirconia copings was determined by surface roughness and marginal fitness. For surface roughness, LUXEN Smile($2.3{\pm}0.9{\mu}m$) block was superior. And the lowest mean values and standard deviations of marginal gap for the HL specimens were $26.5{\pm}2.1{\mu}m$ for buccal, $27.2{\pm}2.1{\mu}m$ for lingual, and that of the HJ specimens $29.6{\pm}4.0{\mu}m$ for mesial, $29.0{\pm}3.0{\mu}m$ for distal. One-way ANOVA showed statistically significant difference between groups for marginal fitness(p<0.05). From the above results, the impression techniques and zirconia blocks had influence on marginal fit of the zirconia copings. Also the marginal fitness of all groups showed clinically acceptable range.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.4
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• pp.245-251
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• 2013

Purpose: This study was conducted to compare in vivo biofilm formation on titanium surface and zirconia surface. Materials and methods: For biofilm formation on titanium and zirconia in oral cavity, after producing oral appliances using acrylic resin and orthodontic wire tailored to 9 subjects, we made titanium and zirconia specimens ($6mm{\times}6mm{\times}2mm$), fixed them on oral appliances and maintained them in oral cavity of test subjects for 24 and 72 hours. Test subjects who have equipped two pairs of specimens maintained oral hygiene not by using toothpaste but only by tooth brushing. After 24 and 72 hours, we removed and observed specimens through scanning electron microscopy (SEM). Results: Biofilm formation showed large deviation depending on individuals. For formation comparison between titanium and zirconia for 24 hours, zirconia showed less biofilm formation than titanium. Biofilm formation showed large deviation depending on individuals. As for formation comparison between zirconia and titanium, the degree of biofilm formation in zirconia was less than it was in titanium after a lapse of 24 hours. The result of biofilm formation in 72 hours trial show that zirconia has an inclination to formate less biofilm than it was in titanium. Conclusion: Based on the above results, we can conclude that early biofilm formation in oral cavity was influenced by difference of abutment materials.