Long-term resin bond to densely sintered aluminum oxide ceramic

Background: Densely sintered aluminium oxide ceramic is a popular material for ceramic copings and all‐ceramic restorations. A strong, predictable, and long‐term durable resin bond is key for long‐term clinical success of bonded alumina‐based restorations. Purpose: The purpose of this study was to measure and compare in vitro shear bond strengths of three resin cements with and without their corresponding silane coupling/bonding agent to air particle‐abraded densely sintered aluminum oxide ceramic after long‐term water storage and thermocycling. Materials and Methods: Composite resin cylinders were bonded to air particle‐abraded samples of densely sintered aluminum oxide ceramic with Noribond DC® (Noritake Dental Supply, Inc., Aichi, Japan), Panavia 21® EX (Kuraray, Osaka, Japan), and Variolink II® (Ivoclar Vivadent, Schaan, Liechtenstein), which were used with and without their corresponding silane coupling and bonding agents (n= 15). All specimens (N= 90) were stored for 180 days in water and subjected to repeated thermocycling for a total of 12,000 cycles before shear bond strength was tested. Data were analyzed with the Kruskal‐Wallis test and the Wilcoxon two‐sample rank sum test at the 5% level of significance. Results: Most groups had no or only minimal bond strength to densely sintered alumina after simulated aging. Panavia had the highest bond strength without silane/bonding agent application. Noribond with its silane/bonding agent revealed the highest overall bond strength, which was significantly greater than that of either Variolink or Panavia after silanization. Conclusions: Resin cements revealed significantly different bond strengths, and the use of silane coupling and bonding agents had various effects on the resin bond to pure densely sintered alumina. CLINICAL SIGNIFICANCE Selection of the proper cement/bonding system is fundamental to clinical long‐term success of bonded alumina‐based restorations. Noribond with its bonding agent and ceramic primer seem to fulfill these requirements under clinically relevant testing conditions.     

The effect of silica coating on the resin bond to the intaglio surface of Procera AllCeram restorations.

OBJECTIVES: This study investigated the influence of a silica-coating method on the resin bond of two different resin composite cements to the intaglio surface of Procera AllCeram densely sintered, high-purity, alumina ceramic restorations after long-term storage and thermocycling. METHOD AND MATERIALS: Densely sintered alumina ceramic specimens were fabricated with the intaglio surface of the Procera AlICeram coping and randomly divided into five adhesive groups (100 total specimens). Resin composite cylinders were bonded either to the untreated or to the tribochemical silica/silane-coated ceramic surface with either a conventional Bis-GMA resin cement or a resin composite containing an adhesive phosphate monomer (Panavia 21) in combination with their corresponding bonding/silane coupling agents. Panavia was also used without silanization to the untreated ceramic surface (control). Subgroups of 10 specimens were stored in distilled water for either 3 (baseline) or 180 days prior to shear bond strength testing. The 180-day samples were subjected to repeated thermocycling for a total of 12,000 cycles. Data were analyzed with one-way analysis of variance and Tukey's multiple comparison. RESULTS: Silica coating significantly increased overall bond strength to Procera AllCeram. RelyX ARC and silica coating revealed the highest bond strength at baseline. Long-term storage and thermocycling significantly decreased overall bond strength. Two groups revealed the significantly highest bond strength values after artificial aging: Panavia 21 with its silane/bonding agent to the original ceramic surface and Panavia 21 to the silica-coated ceramic surface. CONCLUSION: The use of a resin composite containing an adhesive phosphate monomer either in combination with a silane coupling/bonding agent or after tribochemical silica/silane coating revealed the highest long-term shear bond strength to the intaglio surface of Procera AllCeram restorations.     

玻璃渗透氧化铝陶瓷树脂粘接耐久性的研究

目的分析含有不同类型酸性树脂单体的硅烷偶联剂及不同类型树脂粘接剂的相互组合对玻璃渗透氧化铝陶瓷树脂粘接耐久性的影响。方法使用3种硅烷偶联剂处理玻璃渗透氧化铝陶瓷的表面,使用2种双重固化树脂粘接剂与之粘接。测量试件在0和30 000次冷热循环后的粘接强度。结果冷热循环前,粘接剂A与未硅烷化处理陶瓷间的粘接强度显著低于其他硅烷化处理组,粘接剂A、B与偶联剂B处理的陶瓷间的粘接强度显著低于其与偶联剂A和C的粘接强度。冷热循环30 000次后,粘接剂A与未硅烷化处理陶瓷组的试件全部脱落;而其他硅烷化处理陶瓷组中,只有偶联剂A处理的陶瓷表面与粘接剂A和B间的粘接强度达到了5 MPa以上。结论使用10-甲基丙烯酰氧癸基磷酸酯作为硅烷水解剂的硅烷偶联剂处理的玻璃渗透氧化铝陶瓷能够与不同类型的树脂粘接剂获得较好的粘接耐久性。     

In vitro evaluation of long-term bonding of Procera AllCeram alumina restorations with a modified resin luting agent

STATEMENT OF PROBLEM: Bonded densely sintered aluminum oxide ceramic restorations such as Procera AllCeram laminates rely on a strong and long-term durable resin bond. Air particle abrasion and a phosphate-modified resin luting agent have the potential to provide such bonds to aluminum oxide ceramics, but their efficacy on the Procera AllCeram intaglio surface is unknown. The inherent microroughness of this surface may influence bond strengths, because micromechanical interlocking is a main contributor for adhesion of resins to ceramic materials. PURPOSE: This study evaluated the bond strength of a phosphate-modified resin luting agent with and without silanization to an air particle-abraded Procera AllCeram intaglio surface compared with a conventional resin-bonding system before and after artificial aging. MATERIAL AND METHODS: Sixty square (10 x 10 x 2 mm) specimens of Procera AllCeram alumina ceramic with the Procera intaglio surface were air particle abraded with aluminum oxide. Composite cylinders (2.9 mm in diameter and 3.0 mm in width) were fabricated with Z-250 composite and bonded to the ceramic specimens with either Panavia 21 TC or Rely X ARC (control) and their corresponding bonding/silane coupling agents. In addition, Panavia was used without silanization as suggested in similar studies. Subgroups of 10 specimens were stored in distilled water for either 3 or 180 days before shear bond strength was tested with a universal testing machine (MPa) until fracture. The 180-day specimens were subjected to thermocycling at 2000 cycles every 30 days (12,000 cycles total). Data were analyzed with 1-way analysis of variance and Tukey's multiple comparison (alpha=.05). Failure modes were examined with a light microscope (original magnification x 25). RESULTS: Differences between short-term and long-term groups were highly significant (P=.000). Bond strength with Rely X ARC and its silane coupling agent (22.75 +/- 4 MPa) decreased significantly (P=.000) after artificial aging (3.32 +/- 3.62 MPa). Panavia 21 after silanization revealed significantly different (P=.003) early (21.42 +/- 4.3 MPa) and late (16.09 +/- 2.37 MPa) bond strengths but achieved the highest bond strength after artificial aging. Bond strengths of Panavia without silanization both early (8.06 +/- 2.1 MPa) and late (6.91 +/- 2.49 MPa) were not significantly different. Failure modes were mainly adhesive at the ceramic surface for all groups. CONCLUSION: Panavia 21 in combination with its corresponding bonding/silane coupling agent can achieve an acceptable resin bond to the air particle-abraded intaglio surface of Procera AllCeram restorations after artificial aging, which had mixed effects on the other investigated groups. The conventional resin luting agent revealed the most dramatic decrease in bond strength.     

Extrusion shear strength between an alumina-based ceramic and three different cements

STATEMENT OF PROBLEM: Surface treatment is an essential step in bonding a ceramic to resin. Alumina ceramics are particularly difficult to prepare for adequate bonding to composite resin cements. PURPOSE: The purpose of this study was to evaluate the bond strength between a densely sintered alumina ceramic and bovine dentin with 2 adhesive resin cements and a resin-modified glass ionomer cement using an extrusion shear strength test. MATERIAL AND METHODS: Alumina cones (n=30), 4 mm in height, 3 mm in diameter at the small end, and with an 8-degree taper, were fabricated. Without any treatment, the cones were cemented in a standardized cavity in 2.5-mm-thick bovine dentin discs using 1 of 3 cement systems: Panavia F, RelyX ARC, or RelyX Luting. The cements were manipulated following the manufacturers' instructions. After 24 hours of storage at 37 degrees C, an extrusion shear test was performed in a universal testing machine at 0.5 mm/min until bonding failure. The data were analyzed using 1-way ANOVA and Tukey HSD test (alpha=.05). All fractured specimens were examined at x25 magnification and classified by fracture mode. Representative specimens were selected for SEM observation. RESULTS: The highest strength values were obtained with Panavia F, and they were significantly higher (P<.05) than each of the other 2 cements, which were not significantly different from each other. Panavia F resulted in predominantly mixed failure and RelyX ARC and RelyX Vitremer showed primarily adhesive failure. CONCLUSIONS: An MDP-containing adhesive system (Panavia F) provides better extrusion bond strength to a high-density alumina ceramic than a Bis-GMA resin luting agent system (RelyX ARC) or a resin-modified glass ionomer cement system (RelyX Luting).     

Bonding between resin luting cement and glass infiltrated alumina-reinforced ceramics with silane coupling agent

The purpose of this study was to evaluate the shear bond strengths of three dual-cured resin luting cements (Linkmax HV, Panavia Fluoro Cement, and RelyX ARC) to glass-infiltrated alumina-reinforced ceramic material and the effect of four silane coupling agents (Clearfil Porcelain Bond, GC Ceramic Primer, Porcelain LinerM, and Tokuso Ceramic Primer) on the bond strength. The two type-shaped of In-Ceram alumina ceramic glass-infiltrated specimens were untreated or treated with one of the four ceramic primers and then cemented together with one of the three dual-cured resin luting cements. Half of the specimens were stored in water at 37 degrees C for 24 h and the other half thermocycled 20,000 times before shear bond strength testing. Surface treatment by all silane coupling agents improved the shear bond strength compared with non-treatment. The specimens treated with Clearfil Porcelain Bond showed significantly greater shear bond strength than any of the other three silane coupling agents regardless of resin luting cements and thermocycling except for the use of Panavia Fluoro Cement at 20,000 thermocycles. When the alumina-reinforced ceramic material was treated with any silane coupling agent except GC Ceramic Primer and cemented with Linkmax HV, no significant differences in bond strength were noted between after water storage and after 20,000 thermocycles. After 20,000 thermocycles, all specimens except for the combined use of Clearfil Porcelain Bond or GC Ceramic Primer and Linkmax HV and GC Ceramic Primer and Panavia Fluoro Cement showed adhesive failures at the ceramic-resin luting cement interface.     

Shear bond strength of resin cements to both ceramic and dentin

STATEMENT OF PROBLEM: All ceramic restorations benefit from resin cement bonding to the tooth. However, the literature is unclear on which cement, ceramic conditioning treatment, and dentin bonding agent produce the highest and longest-lasting bond strength. PURPOSE: This in vitro study evaluated immediate and 6-month shear bond strengths between a feldspathic ceramic and 4 different resin cements with the use of 6 different surface-conditioning treatments. Shear bond strengths between the 4 resin cements and dentin also were measured. MATERIAL AND METHODS: Four hundred eighty discs (10 mm in diameter and 4 mm thick) of Ceramco II porcelain were randomly divided into 6 main groups (n = 80). The ceramic specimens received 6 different surface conditioning treatments before the application of resin cement. These surface treatments were sanding with 600-grit silicon carbide paper, microetching with aluminum oxide, sanding followed by silane application, microetching followed by silane application, hydrofluoric acid-etching, and hydrofluoric acid-etching followed by silane application. Each group then was subdivided into 4 subgroups (n = 20) for the application of 1 of 4 cements: Nexus, Panavia 21, RelyX ARC, and Calibra. All cemented specimens were tested under shear loading until fracture on a universal testing machine; the load at fracture was reported in MPa as the bond strength. Bond strengths were determined at 24 hours and after 6 months of specimen storage in a saline solution. For dentin-resin cement shear bond strength testing, dentin specimens were treated with dentin bonding agents, and a thin layer of resin cement was applied according to the manufacturer's directions. Prodigy composite was bonded to the cement. Shear bond strengths were determined as above and reported in MPa at fracture. Data were analyzed with 3-way analysis of variance (P<.01). RESULTS: Hydrofluoric acid-etching followed by silane application produced bond strengths (15.0 +/- 7.4 to 21.8 +/- 5.8 MPa) in the highest statistical group with all 4 cements at both 24 hours and 6 months (P<.01). Sanding with 600-grit silicon carbide paper and microetching with aluminum oxide produced the lowest bond strengths (0.0 to 4.0 +/- 3.5 MPa). At 24 hours and 6 months, there were no significant differences among the 4 cements when hydrofluoric acid-etching was followed by silane application. Both auto- and light-polymerized dentin bonding agents bonded better to dentin than dual-polymerized bonding agents. CONCLUSION: Within the limitations of this study, hydrofluoric acid-etching followed by silane application produced the best bonds at 24 hours and 6 months with all 4 cements. Auto- and light-polymerized adhesives were associated with higher bond strengths to dentin than dual-polymerized adhesives.     

Bonding to densely sintered alumina surfaces: effect of sandblasting and silica coating on shear bond strength of luting cements

PURPOSE: An important determinant of the clinical success of ceramic restorations is the bond strength of the luting agent to the seating surface and the prepared tooth structures. Manufacturers of ceramic systems frequently specify both the luting agent and preluting treatment of the seating surface of the crown. Procera AllCeram is an all-ceramic crown comprising a porcelain-veneered coping of densely sintered, high-purity aluminum oxide. This study evaluated the shear bond strength of 4 luting agents: zinc-phosphate, glass-ionomer, resin-modified glass-ionomer, and resin cement (dual cured) to Procera aluminum oxide coping material. The luting agents were subjected to different surface treatments: untreated, sandblasted, or silica coated by the Rocatec system. MATERIALS AND METHODS: Cylindric and cubic specimens of the coping material were luted together, and the shear force necessary to separate the cylinder from the cube was measured with a universal testing machine. The surfaces of the specimens were also analyzed. RESULTS: No significant differences were recorded for the shear bond strengths of the luting agents to the untreated aluminum oxide. Glass-ionomer and the resin-modified glass-ionomer cements had the highest values (4.2 +/- 2.5 MPa and 4.3 +/- 1.9 MPa, respectively), and the lowest were 3.3 +/- 2.3 MPa for the resin cement and 3.2 +/- 1.0 MPa for the zinc-phosphate cement. Similar results were recorded for the sandblasted aluminum oxide surfaces, except with the glass-ionomer, which was significantly higher (12.9 +/- 2.4 MPa). For all 4 luting agents, the highest shear bond strength values were recorded for the silica-coated specimens; the highest was for the resin cement, at 36.2 +/- 7.8 MPa. CONCLUSION: The bond strengths between resin cement and aluminum oxide specimens treated by the Rocatec system were significantly higher than those of the other materials and surface treatments evaluated.     

纳米硅涂层对玻璃渗透氧化铝陶瓷粘结强度的影响

目的：探讨利用溶胶凝胶法进行纳米硅涂层表面改性对玻璃渗透氧化铝陶瓷粘结强度的影响。方法：3组In-Ceram氧化铝瓷块分别施以“喷砂（P组）”、“喷砂＋硅烷偶联（PO组）”、“喷砂＋纳米硅涂层＋硅烷偶联（PTO）组）”的表面处理。制作陶瓷／复合树脂粘结体,室温下置蒸馏水中浸泡24h,微拉伸法测试各组试件粘结强度。结果：P组与PO组粘结强度较弱且无明显差异（P=0．797）,PTO组的粘结强度明显高于其他组（P〈0．05）。结论：通过溶胶凝胶法在喷砂表面制备纳米硅涂层后应用硅烷偶联剂可以显著提高In-Ceram氧化铝陶瓷的粘结强度。     

硅涂层对牙科氧化铝陶瓷与树脂粘结强度的影响

目的 探讨在牙科氧化铝陶瓷表面进行SiO2水溶胶涂层对陶瓷与树脂粘结强度的影响.方法 32个氧化铝陶瓷试件根据计算机产生的伪随机数字表分为4组,每组8个,采用溶胶-凝胶法在试件表面分别进行20%SiO2水溶胶涂层+硅烷偶联剂(A组)、30%SiO2水溶胶涂层+硅烷偶联剂(B组)、40%溶胶涂层+硅烷偶联剂(C组)和硅烷偶联剂(对照组)处理,应用傅立叶红外光谱、扫描电镜、X射线能谱仪进行分析.制作陶瓷-复合树脂粘结体,剪切法测试各组剪切粘结强度.结果 溶胶-凝胶法可在氧化铝陶瓷试件表面制得纳米硅涂层.热处理后A、B、C 3组试件Si-O-Si反对称伸缩振动吸收峰、对称伸缩振动吸收峰、弯曲振动吸收峰均增强;扫描电镜显示纳米氧化硅粒子分布较均匀,局部粒子产生团聚;试件表面硅元素含量均明显增加.A、B、C组试件与树脂的剪切粘结强度分别为(3.196±0.171)Mpa、(4.852±0.178)Mpa、(3.576±0.671)Mpa,与对照组[(1.881±0.156)Mpa]相比,差异均有统计学意义(P＜0.05);B组的剪切粘结强度与A、C组相比,差异有统计学意义(P＜0.05).结论 3种浓度硅溶胶可在牙科氧化铝陶瓷表面制得纳米硅涂层.纳米硅涂层可显著提高氧化铝陶瓷与树脂的剪切粘结强度.其中30%浓度SiO2水溶胶制备的硅涂层提高剪切粘结强度的效果最明显.     

不同树脂水门汀和瓷表面处理对玻璃陶瓷粘结强度的影响

目的：评价4种不同的树脂水门汀以及2种不同的瓷表面处理方法对玻璃陶瓷粘结强度的影响。方法：选用IPse．Max Press热压铸瓷制作直径分别为5mm和4mm,高2mm的圆柱形瓷片。经打磨抛光后分为喇大组：（1）4％氢氟酸酸蚀40sec,（2）4％氢氟酸酸蚀40sec＋硅烷化处理1min。各组内分别选用VariolinkII,Multflink Sprint,RelyX Unicem,BisCem将大小瓷片成对粘固。再分别经37℃水储24h,以及水储后冷热循环5000次测定剪切强度,并用电镜观察瓷片表面形态。结果：硅烷化处理能明显提高粘结强度。经HF＋硅烷处理后Multflink Sprint（31．7±4．5MPa）,BisCem（29．2±4．4MPa）和RelyX Unicem（28．1±5．5MPa）3组显示出较VafiolinkII（21．8±4．2MPa）高的粘结强度。冷热循环后除硅烷处理且用VariolinkII和RelyX Unicem粘固的实验组外,其余各组粘结强度均显著下降。结论：4种树脂水门汀与经HF和硅烷联合处理的玻璃陶瓷问能达到理想的粘结强度。     

Influence of simplified silica coating method on the bonding strength of resin cement to dental alloy

This study evaluated the effectiveness of a simplified silica coating method (CoJet System) on the bonding strength of resin cements to dental alloy. Bonding strength of the specimens treated with metal primer after alumina sandblasting was compared with those treated with silica coating and silane coupling agent after alumina sandblasting. Furthermore, the influence of silane coupling agent on bonding strength was compared between one-liquid and two-liquid silane coupling agents. Measurement of shear bond strength before and after thermal cycling revealed that the group treated with silica coating in one step without alumina sandblasting yielded high bonding strength. As for the influence of silane coupling agent, treatment with two-liquid silane coupling agent achieved higher mean shear bond strength than with one-liquid silane coupling agent. Findings in this study indicated that silicatization by means of this simplified silica coating method was effective in improving the bonding strength to dental alloy.     

长链硅烷偶联剂对瓷和树脂粘接强度影响的实验研究

目的：比较不同浓度、不同溶剂长链硅烷偶联剂对瓷和树脂粘接强度的影响。方法：将6种自制长链硅烷偶联剂与2种商品偶联剂处理铸瓷表面,然后采用2种树脂水门汀粘接瓷试件。对粘接试件进行即刻和老化剪切强度测试。结果：长链硅烷偶联剂能显著提高瓷和树脂的粘接强度,其中即刻粘接强度与商品偶联剂效果无显著差异（P〉0．05）;2％、4％长链硅烷乙醇溶液处理组的老化剪切强度显著高于商品偶联剂（P〈0．05）。结论：长链硅烷偶联剂的粘接耐久性优于短链商品偶联剂,其2％乙醇溶液适用于铸瓷修复体表面处理。     

溶胶-凝胶法制备硅涂层提高牙科高强度陶瓷与复合树脂的粘接强度

目的:探讨溶胶-凝胶法在牙科高强度陶瓷表面改性对陶瓷和复合树脂粘接强度的影响。方法:喷砂玻璃氧化铝陶瓷和氧化锆陶瓷片各72片,每种陶瓷随机分为4组,每组18片,采取以下处理:A组,硅烷偶联剂;B组,20%硅溶胶涂层+硅烷偶联剂;C组,30%硅溶胶涂层+硅烷偶联剂;(D)40%硅溶胶涂层+硅烷偶联剂,制作陶瓷-复合树脂粘接体;每组样本再分为2个亚组,分别在37℃水浴中放置24 h和30 d后,测定陶瓷和树脂的剪切粘接强度。结果:2种陶瓷水浴24 h后,各涂层组粘接强度与单纯硅烷偶联剂组相比差异有统计学意义,其中30%硅溶胶处理组的粘接强度最高(P<0.05)。水浴30 d后,各组粘接强度均和水浴初期(24 h)相比差异无统计学意义,30%硅溶胶处理组的粘接强度最高(P<0.05)。结论:牙科氧化铝陶瓷和氧化锆陶瓷经过溶胶凝胶法纳米硅涂层表面改性结合硅烷偶联剂的处理可以显著提高陶瓷和树脂的粘接强度,并保持较好的粘接耐久性,30%硅溶胶提高粘接强度的效果最好。     

In vitro evaluation of shear bond strengths of resin to densely-sintered high-purity zirconium-oxide ceramic after long-term storage and thermal cycling

STATEMENT OF PROBLEM: The few available studies on the resin bond to zirconium-oxide ceramic recommend airborne-particle abrasion and modified resin luting agents containing adhesive monomers for superior and long-term durable bond strengths. It is unknown whether this regimen can also be successfully applied to the intaglio surface of a commercial zirconia-based all-ceramic system. PURPOSE: The purpose of this study was to evaluate and compare bond strengths of different bonding/silane coupling agents and resin luting agents to zirconia ceramic before and after artificial aging. MATERIAL AND METHODS: Composite cylinders (2.9 mm x 3.0 mm) were bonded to airborne-particle-abraded intaglio surfaces of Procera AllZirkon specimens (n=80) with either Panavia F (PAN) or Rely X ARC (REL) resin luting agents after pretreatment with Clearfil SE Bond/ Porcelain Bond Activator (Group SE). In another group, Rely X ARC was used with its bonding/silane coupling agent (Single Bond/Ceramic Primer, Group SB). PAN without any bonding/silane agent (Group NO) was the control. Subgroups of 10 specimens were stored in distilled water for either 3 or 180 days before shear bond strength was tested. One hundred eighty-day-old specimens were repeatedly thermal cycled for 12,000 cycles between 5 and 60 degrees C with a 15-second dwell time. Data were analyzed with 1- and 2-way analysis of variance and the Tukey multiple comparisons test (alpha=.05). Failure modes were examined under original magnification x25. RESULTS: After 3 days, SE-REL (25.15 +/- 3.48 MPa) and SE-PAN (20.14 +/- 2.59 MPa) groups had significantly superior mean shear bond strengths (P=.0007) compared with either NO-PAN (17.36 +/- 3.05 MPa) or SB-REL (16.90 +/- 7.22 MPa). SE-PAN, NO-PAN, and SB-REL groups were not significantly different. Artificial aging significantly reduced bond strengths. After 180-day storage, SE-PAN (16.85 +/- 3.72 MPa), and SE-REL (15.45 +/- 3.79 MPa) groups demonstrated significantly higher shear bond strengths than NO-PAN (9.45 +/- 5.06 MPa) or SB-REL (1.08 +/- 1.85 MPa) groups. The modes of failure varied among 3-day groups but were 100% adhesive at the ceramic surfaces after artificial aging. CONCLUSION: Artificial aging significantly reduced bond strength. A bonding/silane coupling agent containing an adhesive phosphate monomer can achieve superior long-term shear bond strength to airborne-particle- abraded Procera AllZirkon restorations with either one of the 2 resin luting agents tested.     

Mechanical Properties of Dual-Cured Resin Luting Agents for Ceramic Restoration

PURPOSE: The aim of the present study was to evaluate mechanical properties, including surface hardness, flexural strength, and flexural modulus, of two dual-cured resin luting agents [Clearfil Esthetic Cement (CEC) and Variolink II (VLII)] irradiated through four thicknesses of leucite ceramics (0, 1, 2, and 3 mm) and to evaluate their shear bond strength to zirconia ceramic (Cercon) using each ceramic primer. MATERIALS AND METHODS: Knoop hardness was measured on a thin layer of resin luting agent on the ceramic surface. Three-point bending tests were performed after 24 hours of storage at 37 degrees C. Two differently shaped zirconia ceramic specimens with or without sandblasting with alumina were treated with each primer. The specimens were then cemented together with each resin luting agent. Half of the specimens were stored in water at 37 degrees C for 24 hours and the other half were thermocycled 5000 times. RESULTS: VLII revealed statistically higher Knoop hardness and flexural modulus than CEC for each thickness of ceramic. No significant differences in flexural strength were observed between VLII and CEC for each ceramic spacer. Reduction of the mechanical properties with increase of ceramic thickness varied for each property; however, these properties were similar in the two materials. Blasting with alumina was significantly effective for increasing shear bond strength of both resin luting agents before and after thermal cycling. The use of Clearfil Ceramic Primer showed the highest shear bond strength and maintained bond durability after 5000 thermocycles. CONCLUSION: Mechanical properties of CEC dual-cured resin luting agent appear adequate for ceramic restorations.     

Resistance to bond degradation between dual-cure resin cements and pre-treated sintered CAD-CAM dental ceramics

Objective: To evaluate the bond stability of resin cements when luted to glass-reinforced alumina and zirconia CAD/CAM dental ceramics. Study design: Eighteen glass-infiltrated alumina and eighteen densely sintered zirconia blocks were randomly conditioned as follows: Group 1: No treatment; Group 2: Sandblasting (125 µm Al2O3-particles); and Group 3: Silica-coating (50 µm silica-modified Al2O3-particles). Composite samples were randomly bonded to the pre-treated ceramic surfaces using different resin cements: Subgroup 1: Clearfil Esthetic Cement (CEC); Subgroup 2: RelyX Unicem (RXU); and Subgroup 3: Calibra (CAL). After 24 h, bonded specimens were cut into 1 ± 0.1 mm2 sticks. One-half of the beams were tested for microtensile bond strength (MTBS). The remaining one-half was immersed in 10 % NaOCl aqueous solution (NaOClaq) for 5 h before testing. The fracture pattern and morphology of the debonded surfaces were assessed with a field emission gun scanning electron microscope (FEG-SEM). A multiple ANOVA was conducted to analyze the contributions of ceramic composition, surface treatment, resin cement type, and chemical challenging to MTBS. The Tukey test was run for multiple comparisons (p < 0.05). Results: After 24 h, CEC luted to pre-treated zirconia achieved the highest MTBS. Using RXU, alumina and zirconia registered comparable MTBS. CAL failed prematurely, except when luted to sandblasted zirconia. After NaOClaq storage, CEC significantly lowered MTBS when luted to zirconia or alumina. RXU decreased MTBS only when bonded to silica-coated alumina. CAL recorded 100 % of pre-testing failures. Micromorphological alterations were evident after NaOClaq immersion. Conclusions: Resin-ceramic interfacial longevity depended on cement selection rather than on surface pre-treatments. The MDP-containing and the self-adhesive resin cements were both suitable for luting CAD/CAM ceramics. Despite both cements being prone to degradation, RXU luted to zirconia or untreated or sandblasted alumina showed the most stable interfaces. CAL experimented spontaneous debonding in all tested groups. Key words:CAD/CAM ceramic, alumina, zirconia, resin cement, surface pre-treatment, sandblasting, silica-coating, chemical aging, bond degradation, microtensile bond strength.     

Shear bond strength of a new resin bonding system to different ceramic restorations

This study evaluated the shear bond strength of a newly developed resin bonding system, including single-liquid ceramic primer and dual-cured resin luting agent, to 5 ceramic materials (feldspathic porcelain, machinable ceramic, In-Ceram Alumina, Procera AllCeram alumina, and Cercon). Ceramic specimens were cleaned with phosphoric acid, treated with primer, and bonded with a resin luting agent. Shear bond strength was determined after 24 hours of immersion in water and/or 10,000 thermocycles. There were no significant differences in bond strength before and after thermocycling for the 5 ceramic materials (P > .05). The findings indicate that the resin bonding system may offer an acceptable performance in terms of clinical success for the 5 ceramic restorations.     

Effects of surface treatments on shear bond strengths between a resin cement and an alumina core

STATEMENT OF PROBLEM: Although bonding to all-ceramic restorations is desirable, there is little information on the use of resin cements containing a phosphate monomer, and the importance of different surface treatments on their adhesion to high-strength core materials. PURPOSE: This study attempted to determine the shear bond strength values between Panavia 21 resin cement (Kuraray) and an alumina core material (In-Ceram) after 3 surface treatments and the application of a silane coupling agent. MATERIAL AND METHODS: Forty-five In-Ceram cylindrical rods were fabricated and assigned to 3 groups. Group I specimens were treated with a 9.5% hydrofluoric (HF) acid, group II with a 5% HF acid, and group III were sandblasted. All specimens were coated with a silane coupling agent (Cavex Clearfil Photobond and Activator) before cementation with Panavia 21 to sandblasted nickel-chromium rods. As a control, group IV consisted of 8 porcelain (Vitadur Alpha) rods treated with a 5% HF acid and silane. All specimens were subjected to a load of 1.2 kg during cementation, then stored under water for 36 hours. A jig mounted on a Hounsfield Universal Testing machine was used at a crosshead speed of 0.5 mm/min to test the shear bond strengths. RESULTS: The results were 14.65 +/- 4.64 MPa for group I, 18.03 +/- 6.13 MPa for group II, and 22.35 +/- 5.98 MPa for group III In-Ceram specimens; and 18.05 +/- 8.46 MPa for control (group IV). CONCLUSION: The use of Panavia 21 resin cement and a silane coupling agent can achieve a successful bond between either sandblasted or 5% HF acid-etched In-Ceram core material.     

3类修复体经3种瓷表面处理后与陶瓷托槽的粘结强度及去托槽后的瓷表面情况

目的研究3种瓷表面处理方法对3类修复体与陶瓷托槽粘结强度的影响以及去除托槽后瓷表面的情况。方法钴铬烤瓷、e-max铸瓷、二氧化锆全瓷3类修复体试件各36个,每类试件随机分为4组。除对照组为6个试件,其余各组每组10个试件。对照组不作任何处理。喷砂组,氧化铝喷砂4 s,冲洗、吹干后表面涂布硅烷偶联剂。磷酸组,质量分数37%磷酸酸蚀1 min,冲洗、吹干后表面涂布硅烷偶联剂。氢氟酸组,氢氟酸酸蚀2 min,冲洗、吹干后表面涂布硅烷偶联剂。使用光固化托槽粘结剂粘结陶瓷托槽。经37℃恒温水浴24 h后检测抗剪强度。观察托槽去除后瓷表面粘结剂残留情况和瓷面破损情况。结果 3种表面处理方法均能达到或超过有效粘结强度。采用喷砂并涂布硅烷偶联剂方法和氢氟酸酸蚀并涂布硅烷偶联剂方法,钴铬烤瓷试件的抗剪强度与e-max铸瓷和二氧化锆全瓷试件比较差异有统计学意义(P<0.05);磷酸酸蚀并涂布硅烷偶联剂方法中,3类修复体的抗剪强度差异无统计学意义(P>0.05)。3类修复体在使用氢氟酸并硅烷偶联剂处理后,抗剪强度较其他2种方法高,差异有统计学意义(P<0.05)。磷酸组的3类修复体瓷表面粘结剂残留指数得分最低,粘接剂残留最少,且瓷表面破坏最小。结论喷砂、磷酸酸蚀、氢氟酸酸蚀合并使用硅烷偶联剂处理钴铬烤瓷、e-max铸瓷、二氧化锆全瓷修复体,均能得到满意的粘结强度,而磷酸结合硅烷偶联剂方法去除托槽后对修复体表面的影响最小。