Effect of silanization on bond strengths of fiber posts to various resin cements.

OBJECTIVES: To investigate the effects of pretreatment (silanization) on bond strengths between 3 different types of fiber posts and 4 resin cements, respectively. METHOD AND MATERIALS: Prefabricated quartz-fiber (Unicore Post, Ultradent) and prefabricated glass-fiber (FRC Postec, Ivoclar Vivadent) posts with a cross-linked polymer matrix and individually formed glass-fiber posts with an interpenetrating polymer network (IPN Post, Stick Tech) (n = 160 each) were inserted into resin composite disks (2 mm thick) using the following resin cements and silane solutions: Panavia F/Porcelain Bond Activator (Kuraray), PermaFlo DC/Silane (Ultradent), Variolink II/Monobond S (Ivoclar Vivadent) and RelyX Unicem/Espe Sil (3M Espe). Nonsilanated posts served as controls. The push-out bond strengths were determined before (n = 10) and after (n = 10) thermocycling (2,000 cycles, 5 degrees C to 55 degrees C, dwelling time 30 seconds). RESULTS: Bond strengths (mean [SD]) were significantly affected by the resin cement (P < .001), the pretreatment (P < .001), and the type of post (P < .001), but not by thermocycling (P = .955, 4-way ANOVA). The IPN post demonstrated significantly higher bond strengths compared to the other posts (P < .05; Tukey B). Silanization significantly increased bond strengths (15.2 [5.2] MPa) compared to those of the control groups (13.9 [4.9] MPa). CONCLUSION: The type of fiber post revealed a significant influence on bond strengths, whereas the effects of silanization appeared to be clinically negligible.     

Effect of silica coating on flexural strength of fiber posts

PURPOSE: Fiber-reinforced composite (FRC) posts can be air-abraded to obtain good attachment to the resin cement. This study tested the effect of silica coating on the flexural strength of carbon, opaque, and translucent quartz FRC posts. MATERIALS AND METHODS: Six experimental groups of FRC posts (n=10 per group) were tested, either as received from the manufacturer or after chairside silica coating (30-microm CoJet-Sand). RESULTS: There was no significant difference in the flexural strength of nonconditioned (504 to 525 MPa) and silica-coated (514 to 565 MPa) specimens (P > .05) (analysis of variance). The type of post did have a significant effect on flexural strength (P < .05). CONCLUSION: Chairside silica coating did not affect the flexural strength of both carbon and quartz FRC posts.     

Effect of adhesive resin cements and post surface silanization on the bond strengths of adhesively inserted fiber posts

This study evaluated the tensile bond strengths and the effect of silanization of fiber posts inserted with different adhesive systems. Sixty DT Light Posts (size 1) were used. Thirty posts were pretreated with silane. The posts were cemented into form-congruent artificial root canals (12 mm) of bovine dentine. Six groups were formed: G1, Prime&Bond NT/Calibra; G2, Monobond-S+Prime&Bond NT/Calibra; G3, ED Primer/Panavia 21ex; G4, Monobond-S+ED Primer/Panavia 21ex; G5, RelyX Unicem; and G6, Monobond-S+RelyX Unicem. The mean (standard deviation) tensile bond strengths (megapascals) were 7.69 (0.85) for G1, 7.15 (1.01) for G2, 6.73 (0.85) for G3, 6.78 (0.97) for G4, 4.79 (0.58) for G5, and 4.74 (0.88) for G6. G1 achieved significantly higher bond strengths than G3 and G5; G3 had significantly higher values than G5 (P < .05; Scheffé procedure). Silanization had no significant effect (P > .05, one-way analysis of variance). Tensile bond strengths were significantly influenced by the type of resin cement. Silanization of fiber post surfaces seems to have no clinical relevance.     

Effect of silica coating and laser treatment on the flexural strength,surface characteristics,and bond strength of a dental zirconia

This study investigated the effect of irradiation with an erbium‐doped yttrium aluminium garnet (Er:YAG) laser and coating with silica on the surface characteristics, bond strength, and flexural strength of dental zirconia. Three hundred and forty‐three standard zirconia specimens were created, and 49 were assigned to each of seven surface treatment groups: (i) no treatment; Er:YAG laser (80 mJ/2 Hz) with pulse widths of 50 μs (ii), 100 μs (iii), 300 μs (iv), or 600 μs (v); or tribochemical silica coating at the partially sintered stage (vi) or after sintering was complete (vii). All specimens were sintered after the surface treatments, except for the group in which specimens were sintered before treatment. The study outcomes were roughness, surface loss, microshear bond strength (μSBS), and biaxial flexural strength (BFS). Mean roughness and surface loss values were significantly higher in specimens from irradiated groups than in those from silica‐coated groups. Regarding μSBS, after aging, specimens from all experimental groups presented very low and similar μSBS values, irrespective of the surface treatment. Silica coating after sintering yielded the highest BFS (1149.5 ± 167.6 MPa), while coating partially sintered specimens with silica resulted a BFS (826.9 ± 60.9 MPa) similar to that of the untreated control group (794.9 ± 101.7 MPa). Laser treatments, irrespective of pulse width used, significantly decreased the BFS. In the group treated with laser at 300 μs pulse width, specimens exhibited the lowest BFS value (514.1 ± 71.5 MPa). Adhesion to zirconia was not stable after aging, regardless of the surface treatment implemented.     

不同表面处理对纤维桩粘结强度的影响及电镜观察

目的 比较研究不同表面处理对纤维桩剪切粘结强度的影响及各自的粘结面超微结构。方法 20根纤维桩分为4组（n=5）：表面无处理组（A）、椅旁硅烷化处理组（B）、厂家预处理组（C）、厂家预处理+椅旁硅烷化处理组（D）。分别用树脂核材料置于纤维桩周围制成圆柱形标准试件,包埋,切割成1 mm薄片。每根纤维桩可获得10个薄片。每组5个薄片用于电镜观察纤维桩与树脂核材料粘结界面的超微结构;45个薄片在万能实验机上进行微推出实验,记录数值并进行统计学分析。结果 各组的剪切粘结强度依次为（13.46±1.78）、（18.39±1.60）、（24.54±1.34）、（24.39±1.65） MPa。表面处理组均高于A组,C组高于B组,D组与C组之间无差异。电镜观察各组纤维桩与树脂核材料粘结界面结合良好。C组和D组的纤维桩粘结界面可见微机械固位结构。结论 纤维桩表面由厂家预处理有效提高了纤维桩剪切粘结强度,表面预处理形成的微机械固位和化学粘结固位是增强纤维桩粘结强度的重要因素。     

Comparison of in vitro tensile bond strengths of luting cements to metallic and tooth-colored posts

The aim of this study was to compare the tensile bond strength of tooth-colored ceramic and carbon-fiber post materials as well as titanium and stainless steel post materials luted with three different kinds of luting cements. Disks of alloy post materials were polished with 600-grit SiC paper, air abraded, and ultrasonically cleaned. Ceramic surfaces were pretreated with hydrofluoric acid and silanized. Panavia F, Vitremer, and ProTec Cem cements were bonded to the post specimens and placed in a humidor for 24 hours. Specimens were placed in a jig, and the debonding values were obtained using a universal testing machine. Means and standard deviations were analyzed by two-way ANOVA. Panavia F provided the highest bond strengths for all types of post materials. ProTec Cem bonded more strongly to stainless steel and titanium than to zirconium oxide. Vitremer results were the lowest. Bonds to carbon-fiber post materials were weaker than to metallic post materials, but stronger than to zirconium oxide. In general, higher bond strengths resulted in a higher percentage of cohesive failures.     

Effects of laser modalities on shear bond strengths of composite superstructure to zirconia and PEEK infrastructures: an in vitro study

Odontology - In the last decade, demand for metal-free esthetic restorations has grown considerably due to the development of materials to fulfill the need for an esthetic prosthesis. We examined...     

In vitro shear bond strength of 2 resin cements to zirconia and lithium disilicate: An in vitro study

Statement of problemThere is little evidence on how the multiple layers of zirconia (ZrO₂) or glazed material will affect the shear bond strength (SBS) of different resin cements.PurposeThe purpose of this in vitro study was to compare the SBS of 2 resin cements with the different layers of a monolithic polychromatic ZrO₂ ceramic, both glazed and nonglazed, and a lithium disilicate (LDS) ceramic.Material and methodsOne hundred and sixty-eight composite resin cylinders and 48 monolithic polychromic ZrO₂ plates were prepared. Twenty-four were milled and sintered, and 24 were milled and sintered and had a glaze cycle applied with no liquid glaze. These plates and 12 LDS plates were mounted in autopolymerized acrylic resin. Bonding surfaces were polished, airborne-particle abraded, and cleaned ultrasonically. The different layers (cubic, hybrid, and tetragonal) of the ZrO₂ plates were identified and marked. The plates were assigned to 2 cement groups: a self-adhesive, autopolymerized resin cement, and a dual-polymerizing, adhesive resin cement (DPRC). Bonding surfaces were cleaned and treated according to the cement manufacturer’s instructions. Three composite resin cylinders were luted to the ZrO₂ plates at the appropriate layer, and 2 cylinders were luted to each LDS plate. The specimens were stored in a moist environment for 24 hours at 37 °C. The SBS test was performed with a universal testing machine. Visual inspections of the debonded surfaces were compared under magnification. The data were analyzed with a 2-way ANOVA and a subsequent Student t test (α=.05).ResultsThe 2-way ANOVA found no difference among luting agent and LDS and ZrO₂. The SBSs of the nonglazed tetragonal and cubic layer to the ZrO₂ were higher than to the surface exposed to a glazing cycle (P=.001). The bonded surfaces were examined tactilely and under ×3.5 magnification, followed by light and scanning electron microscopy and recorded as either adhesive, cohesive, or mixed. Almost all failures in the glazed ZrO₂ were mixed and cohesive. However, more adhesive failures were observed in the DPRC group of nonglazed ZrO₂.ConclusionsNo differences were found between the 2 luting agents for the LDS. For the ZrO₂ cubic and tetragonal layers, the DPRC had higher bond strengths to the nonglazed surfaces.     

Metal-reinforced glass ionomers: their flexural and bond strengths to tooth substrates

This study compared the flexural strengths and bond strengths to dentin and enamel of two brands of silver-reinforced glass ionomers with their respective unfilled glass-ionomer cements for luting. The results led to the following conclusions. 1. No significant differences in bond strengths to tooth substrates were recorded between silver-reinforced and unfilled glass ionomers. 2. Although the mean bond-strength values of enamel were higher than those of dentin, no statistically significant differences were observed. 3. No significant differences in bond strengths to tooth substrates were observed between the two brands of glass ionomers studied. 4. No differences in flexural strengths were recorded between the silver-reinforced glass ionomer and glass ionomer of a similar brand for luting. 5. Ketac-Silver and Ketac-Cem cements had significantly higher flexural strength than Fuji II Lumi Alloy and Fuji I cements.     

The effect of silane on the bond strengths of fiber posts.

OBJECTIVES: Esthetic posts have been developed to maximize the foundation of esthetic restorations. The purpose of this study was to evaluate the effect of silane on the bond strength of three fiber-reinforced resin posts (fiber posts). METHODS: Fifty-four extracted human maxillary central incisors and canines were endodontically treated. D.T. Light Post (DT, Bisco), FRC Postec (FR, Ivoclar Vivadent), and ParaPost Fiber White (PP, Coltène/Whaledent) were inserted using the resin adhesive system provided by the respective manufacturer. For half of the specimens in each group, the fiber posts were treated with a silane solution (Monobond S, Ivoclar Vivadent). A push-out test was performed on three different sections of each root to measure bond strengths. Data were analyzed with ANOVA and Bonferroni's post hoc test at P<0.05. RESULTS: The use of silane did not result in any statistically significant difference at any level of the root. Silane did not result in any significant different bond strengths (MPa) for each of the posts. When the data were pooled, the use of silane did not result in statistically significant different bond strengths at P>0.403: No silane=12.7+/-8.4; Silane=14.1+/-7.0. The coronal third of the root (17.5+/-6.7) resulted in statistically greater bond strengths than the medium third (12.9+/-6.8) and than the apical third (9.8+/-7.3) at P<0.002 and P<0.0001, respectively. The medium third and the apical third resulted in no statistically significant different bond strengths from each other at P>0.07. The type of post did not result in statistically significant different bond strengths at P>0.417: DT=14.7+/-6.8 MPa; FR=13.3+/-6.6 MPa; PP=12.2+/-6.6 MPa. SIGNIFICANCE: The use of a silane coupling agent did not increase the push-out bond strengths of the three fiber posts used in this study. All posts bonded to root dentin at the same magnitude. Bonding is more predictable at the most coronal level of the root.     

摩擦化学法硅涂层对氧化锆陶瓷粘接强度的影响

目的： 评估摩擦化学法硅涂层对氧化锆陶瓷粘接强度的影响。方法： 将切割烧结后的Lava氧化锆瓷块60件分为6组,每2组分别经喷砂/硅烷偶联剂、喷砂/CoJet Sand/硅烷偶联剂、无处理3种表面处理后,相同表面处理的2组中,每组分别用RelyX Unicem或Panavia F2.0与牙釉质粘接。各组随机抽取5件共30件进行24 h水浴,其余30件进行5000周水热循环,然后进行剪切粘接强度测试。采用SPSS 23.0软件包对数据进行双因素方差分析、Tukey HSD多重比较法及t检验。结果： 喷砂/CoJet/硅烷组的剪切强度均显著高于其他2组（P<0.001）;经老化试验后,喷砂/CoJet/硅烷组使用RelyX Unicem仍保持较高的剪切强度[(21.374±4.433)MPa],与其他各组相比有显著差异（P<0.001）。结论： 摩擦化学法硅涂层能够有效提高氧化锆的粘接强度及耐久性,表面处理方式与粘接剂之间的相互作用需得到临床关注。     

Tensile bond strength of intracanal posts in primary anterior teeth: an in vitro study

The aim of this study was to measure in vitro; the tensile bond strength of three intracanal posts used in anterior primary teeth. A total of 45 single rooted primary anterior teeth were selected for the study and the crowns sectioned leaving 1mm above the cement-enamel junction. The roots were then assigned to three groups according the type of retention used. All roots were endodonticaly treated, a 4-mm of the canal was cleansed and a base of glass ionomer cement was put at the bottom of the prepared canal. The roots were then prepared to receive intracanal posts using a # 4137 diamond bur (KG Sorensen) used in a depth of 3-mm of the length of the canal All the prepared roots were acid etched with a 37% phosphoric acid gel for 15 seconds, rinsed, dried and the dentin adhesive Single Bond (3M) was applied. Group I received intracanal posts and cores made of composite resin (Filtek Z 250, 3M). Group II intracanal posts were made from a 0.6mm orthodontic wire bent as a Greek letter type (gamma), fixed with the Z 250 composite resin and cores were built with the same composite. Finally Group III received intracanal retention made of a fiber glass post (Fibrekor Post, Generic/Pentron) with 1.25 mm diameter, fixed with Z 250 and cores were made like the other groups. The samples were submitted to tension in a universal-testing machine (Instron, model 4444). Statistical analysis (ANOVA) revealed that there were no statistically significant differences between the groups. On the basis of the results of this in vitro study it was concluded that the type of intracanal post did not interfere with the tensile strength and the most frequent type of failure was of adhesive type, corresponding to 74% of the sample.     

Effects of different irrigating solutions and disinfection methods on push-out bond strengths of fiber posts

Objective. The aim of this study was to evaluate the effects of various irrigating solutions and photoactivated disinfection (PAD) on the push-out bond strengths of fiber posts to root dentin. Materials and methods. Thirty-two human teeth were divided into eight groups, as follows: (1) irrigation with physiologic saline (control), (2) NaOCl irrigation, (3) chlorhexidine (CHX) irrigation, (4) ethanol (EtOH) irrigation, (5) NaOCl followed by 17% EDTA irrigation, (6) NaOCl-EDTA supplemented with CHX irrigation, (7) NaOCl-EDTA supplemented with EtOH irrigation and (8) NaOCl-EDTA irrigation supplemented with PAD. After the posts were cemented, the roots were transversally sectioned to obtain four slices (1 mm thick) (n = 16). Push-out tests were conducted by applying a load at 0.5 mm/min, types of fracture failures were recorded and data were analyzed with one-way ANOVA and Tukey post-hoc tests (p = 0.05). Results. Push-out bond strength was significantly affected by the type of irrigating solution and the disinfection protocol (p < 0.05). The bond strength of the EtOH, NaOCl and NaOCl-EDTA-CHX irrigated groups was significantly higher than that of the other groups. The highest bond strength was observed in the EtOH irrigated group and the lowest was the NaOCl-EDTA irrigated group. Conclusions. Irrigation with NaOCl and EDTA combined caused lower bond strength than observed in the control group. However, supplementing this combination with CHX improved the post-dentin bond strengths; supplementing with PAD did not.     

氧化锆基底和饰瓷结合强度的分析

目的分析和比较几种全瓷系统基底和饰瓷的结合强度。方法制作直径为8 mm、厚度为3 mm的Lava、 Cercon、IPS e.max ZirCAD、Procera试件各20个,分别为Lava组、Cercon组、IPS e.max ZirCAD组、Procera组。每组各选10个试件表面烤制厚度为1 mm的相应饰瓷,10个试件表面烤制厚度为2 mm的相应饰瓷。对试件进行剪切强度的测定和断裂模式的观察。结果饰瓷厚度为1 mm时,Lava、Cercon、IPS e.max ZirCAD、Procera组的剪切强度分别为：（13.82±3.71）、（13.24±2.09）、（6.37±4.15）、（5.19±5.31）MPa;饰瓷厚度为2 mm时,各组的剪切强度分别为：（38.77±1.69）、（21.67±3.34）、（12.70±4.24）、（9.94±6.67）MPa。Lava组和Cercon组的剪切强度高于IPS e.max ZirCAD组和Procera组（P<0.05）,饰瓷厚度为2 mm的试件的剪切强度高于饰瓷厚度为1 mm的试件（P<0.05）。各组试件破坏模式均以界面破坏为主。结论氧化锆基底和饰瓷的结合强度因基底材料的不同而不同,饰瓷的厚度对结合强度有明显的影响。     

Effect of priming agents on shear bond strengths of resin-based luting agents to a translucent zirconia material

Purpose

The purpose of the present study was to evaluate the effect of priming agents and artificial aging with thermocycling on shear bond strengths of two resin-based luting agents to a translucent zirconia material.

Four-point flexural strength and microtensile bond strength of digitally and conventionally veneered zirconia

This study intended to evaluate the effect of digital veneering on four-point flexural strength (FS) and microtensile bond strength (μTBS) of veneered zirconia. Two different zirconia blocks, a lithium disilicate and a feldspathic ceramic block, and two different layering ceramics were used. IPS e.max Zir CAD (ZC) and Vita In-Ceram YZ (YZ) with yttria stabilized tetragonal zirconia polycrystals (3Y-TZP) were used as substructures. IPS e.max CAD (LD), Vita Mark II (VMII), IPS e.max Ceram (EC) and Vita VM9 (VM9) were used for veneering. Resin cement and fusion ceramic were placed between veneer and zirconia substructure for digital veneering. A total of one hundred and fifty specimens in five groups (n = 30) were prepared for FS and tested in universal machine at 1.0 mm/min. One hundred specimens in five groups (n = 20) were obtained for the μTBS and tested at 1.0 mm/min. Statistical analysis was made by one way ANOVA and Tukey HSD. Conventional veneering showed statistically significant FS. ZC veneered with EC had the highest mean FS and the lowest was obtained in groups veneered through resin cement. YZ layered with VM9 had the highest mean μTBS. ZC veneered through fusion ceramic and YZ veneered through resin cement showed significantly lower and similar μTBS.