Effect of silane activation on shear bond strength of fiber-reinforced composite post to resin cement

PURPOSE

Among the surface treatment methods suggested to enhance the adhesion of resin cement to fiber-reinforced composite posts, conflicting results have been obtained with silanization. In this study, the effects of silanization, heat activation after silanization, on the bond strength between fiber-reinforced composite post and resin cement were determined.

MATERIALS AND METHODS

Six groups (n=7) were established to evaluate two types of fiber post (FRC Postec Plus, D.T. Light Post) and three surface treatments (no treatment; air drying; drying at 38℃). Every specimen were bonded with dual-curing resin cement (Variolink N) and stored in distilled water for 24 hours at 37℃. Shear-bond strength (MPa) between the fiber post and the resin cement were measured using universal testing device. The data were analyzed with 1-way ANOVA and by multiple comparisons according to Tukey''s HSD (α=0.05). The effect of surface treatment, fiber post type, and the interactions between these two factors were analyzed using 2-way ANOVA and independent sample T-tests.

RESULTS

Silanization of the FRC Postec Plus significantly increased bond strength compared with the respective non-treated control, whereas no effect was determined for the D.T. Light Post. Heat drying the silane coupling agent on to the fiber-reinforced post did not significantly improve bond strength compared to air-syringe drying.

CONCLUSION

The bond strength between the fiber-reinforced post and the resin cement was significantly increased with silanization in regards to the FRC Postec Plus post. Bond strength was not significantly improved by heat activation of the silane coupling agent.     

The effect of adhesive systems on the pullout strength of a fiberglass-reinforced composite post system in bovine teeth

PURPOSE: To evaluate the pullout strength of a glass fiber-reinforced composite post (glass FRC) cemented with three different adhesive systems and one resin cement. The null hypothesis was that pullout strengths yielded by the adhesive systems are similar. MATERIALS AND METHODS: Thirty bovine teeth were selected. The size of the specimens was standardized at 16 mm by sectioning off the coronal portion and part of the root. The specimens were divided into three groups, according to the adhesive system, which were applied following the manufacturers' instructions: G1, ScotchBond Multi-Purpose Plus; G2, Single Bond; G3, Tyrian SPE/One-Step Plus. The glass FRCs (Reforpost) were etched with 37% H3PO4 for 1 min and silanized (Porcelain Primer). Thereafter, they were cemented with the dual resin cement En-Force. The specimens were stored for 24 h, attached to an adapted device, and submitted to the pullout test in a universal testing machine (1 mm/min). The data were submitted to the one-way ANOVA and Tukey's test (alpha = 0.05). RESULTS: G1 (30.2 +/- 5.8 Kgf) displayed the highest pullout strength (p < 0.001) when compared to G2 (18.6 +/- 5.8 Kgf) and G3 (14.3 +/- 5.8 Kgf), which were statistically similar. Analysis of the specimens revealed that all failures occurred between the adhesive system and the root dentin (pullout of the post cement), regardless of group. CONCLUSION: The multiple-bottle, total-etch adhesive system provided higher pullout strength of the glass FRC when compared to the single-bottle, total-etch, and single-step self-etching adhesive systems. The null hypothesis was rejected (p < 0.001).     

粘结层厚度对纤维桩在根管内剪切粘结强度的影响

目的:研究3种不同粘结层厚度在不同根管部位对纤维桩粘结强度的影响。方法:取18个离体上颌单根管前牙,常规根管治疗后根据不同桩道预备直径随机分为3组。Ⅰ组:直径1.2 mm的RTD纤维桩配套钻头预备桩道;Ⅱ组:直径1.4 mm的RTD纤维桩配套钻头预备桩道;Ⅲ组:直径1.6 mm的RTD纤维桩配套钻头预备桩道。桩道预备后使用酸蚀加自粘结材料(320 g/L磷酸+RelyXUnicem)对纤维桩进行粘结,之后将粘结有纤维桩的牙根切割成1 mm厚度的薄片,标记根管冠部、中部和尖部。用金相显微镜对每个薄片上粘结层的厚度进行测量,然后进行薄片推出测试,记录薄片推出力值并在光学显微镜下观察薄片的破坏方式。结果:不同粘结层厚度在不同根管段内均对纤维桩粘结强度有影响,在根管各段均以I组粘结强度最大,Ⅱ组次之,Ⅲ组最小,组间比较差异有统计学意义(P<0.05)。结论:粘结层的厚度对纤维桩在根管内的粘结强度有影响,纤维桩直径与桩道相匹配,即粘结层厚度较薄时粘结强度最高。     

Microtensile bond strength between a quartz fiber post and a resin cement: effect of post surface conditioning

PURPOSE: To test the bond strength between a quartz-fiber-reinforced composite post (FRC) and a resin cement. The null hypothesis was that the bond strength can be increased by using a chairside tribochemical silica-coating system. MATERIALS AND METHODS: Thirty quartz-FRCs (Light-Post) were divided into 3 groups according to the post surface treatment: G1) Conditioning with 32% phosphoric acid (1 min), applying a silane coupling agent; G2) etching with 10% hydrofluoric acid (1 min), silane application; G3) chairside tribochemical silica coating method (CoJet System): air abrasion with 30-microm SiOx-modified Al2O3 particles, silane application. Thereafter, the posts were cemented into a cylinder (5 mm diameter, 15 mm height) with a resin cement (Duo-Link). After cementation, the specimens were stored in distilled water (37 degrees C/24 h) and sectioned along the x and y axes with a diamond wheel under cooling (Lab-cut 1010) to create nontrimmed bar specimens. Each specimen was attached with cyanoacrylate to an apparatus adapted for the microtensile test. Microtensile testing was conducted on a universal testing machine (1 mm/min). The data obtained were submitted to the one-way ANOVA and Tukey test (alpha = 0.05). RESULTS: A significant influence of the conditioning methods was observed (p < 0.0001). The bond strength of G3 (15.14 +/- 3.3) was significantly higher than the bond strengths of G1 (6.9 +/- 2.3) and G2 (12.60 +/- 2.8) (p = 0.000106 and p = 0.002631, respectively). Notwithstanding the groups, all the tested specimens showed adhesive failure between the resin cement and FRC. CONCLUSION: The chairside tribochemical system yielded the highest bond strength between resin cement and quartz-fiber post. The null hypothesis was accepted (p < 0.0001).     

The effect of cement thickness on the fracture strength of all-ceramic crowns

The effect of increasing cement thickness on the fracture strength of aluminous porcelain jacket crowns was investigated in this study. Thirty-three aluminous porcelain jacket crowns were divided into three groups. In Group 1, only platinum foil was used to provide cement space. In Group 2 two layers and Group 3 four layers of die spacer were painted onto the metal die before impression taking. Each crown was cemented onto a metal die with zinc phosphate cement and loaded until fracture. The maximum force to break each crown was recorded. The average fracture load was 408 N for Group 1,365 N for Group 2 and 324 N for Group 3. ANOVA (SPSS) found a significant difference (p < 0.05) between groups. A Scheffe Test revealed a significant difference between Groups 1 and 3. It was concluded that increasing the cement thickness above 70 μm reduced the fracture strength of porcelain jacket crowns.     

Effects of post surface conditioning before silanization on bond strength between fiber post and resin cement

PURPOSE

Post surface conditioning is necessary to expose the glass fibers to enable bonding between fiber post and resin cement. The purpose of the present study was to evaluate the effect of different surface conditioning on tensile bond strength (TBS) of a glass fiber reinforced post to resin cement.

MATERIALS AND METHODS

In this in vitro study, 40 extracted single canal central incisors were endodontically treated and post spaces were prepared. The teeth were divided into four groups according to the methods of post surface treatment (n=10): 1) Silanization after etching with 20% H₂O₂, 2) Silanization after airborne-particle abrasion, 3) Silanization, and 4) No conditioning (Control). Adhesive resin cement (Panavia F 2.0) was used for cementation of the fiber posts to the root canal dentin. Three slices of 3 mm thick were obtained from each root. A universal testing machine was used with a cross-head speed of 1 mm/minute for performing the push-out tests. Two-way ANOVA and Tukey post hoc tests were used for analyzing data (α=0.05).

RESULTS

It is revealed that different surface treatments and root dentin regions had significant effects on TBS, but the interaction between surface treatments and root canal regions had no significant effect on TBS. There was significant difference among H₂O₂ + Silane Group and other three groups.

CONCLUSION

There were significant differences among the mean TBS values of different surface treatments. Application of hydrogen peroxide before silanization increased the bond strength between resin cements and fiber posts. The mean TBS mean values was significantly greater in the coronal region of root canal than the middle and apical thirds.     

The effect of film thickness on the tensile bond strength of a prosthodontic adhesive.

This study investigated the effect of cement film thickness on the tensile bond strength of a prosthodontic adhesive. Rexillium III alloy cylinders were bonded end-to-end with Panavia Opaque adhesive cement and film thicknesses of 20, 50, 80, 110, 140, and 200 microns were evaluated. The specimens were thermocycled for 24 hours (1080 cycles) between 5 degrees and 60 degrees C, stored for 30 days at 37 degrees C, and the mean bonds for tensile strength, including the mode of failures, were recorded. Statistical analysis revealed significant differences, but the strongest bond strengths were recorded for the 80 microns cement film thickness.     

表面不同处理方法对POPO纤维桩粘接固位力的影响

目的讨论不同表面处理方法对POPO纤维桩粘接固位力的影响。方法取50根POPO纤维桩,根据表面不同处理方法随机分为5组,每组10根。A组：不处理;B组：硅烷化处理60 s;C组：酸蚀处理30 s;D组：酸蚀处理60 s;E组：酸蚀处理120 s。选取45颗离体前磨牙截冠后随机分到5个实验组,树脂粘接纤维桩于根管内,包埋后在电子万能试验机上进行拉力测试。扫描电镜（SEM）观察处理后POPO纤维桩的表面形态。结果不同表面处理方法时纤维桩粘接力差异有统计学意义（P<0.05）,D组的粘接力最大,为（207.33±7.58）N。D组和E组间粘接固位力差异有统计学意义（P=0.027）,D组和C组间粘接固位力差异无统计学意义（P=0.112）。SEM观察处理后纤维桩的表面树脂基质粗糙度及纤维暴露数量有明显改变。结论不同表面处理方法增强了POPO纤维桩的粘接固位力。     

The effect of dentin-cleaning agents on resin cement bond strength to dentin

BACKGROUND: Provisional cement remnants on dentin affect the bond strength of resin cements to dentin. The authors investigated the effects of dentin-cleaning agents and etching systems on the bond strength of adhesive resin cement. METHODS: The authors removed the provisional cement from the dentin surfaces of the specimens and then cleaned the surfaces with the dentin-cleaning agents Sikko Tim (VOCO GmbH, Cuxhaven, Germany), Cavity Cleanser (Bisco, Schaumburg, Ill.) or Consepsis Scrub (Ultradent, South Jordan, Utah). They used adhesive resin cement after applying the different etching adhesive systems. Then they examined the dentin surfaces by using scanning electron microscopy. RESULTS: The authors analyzed data by means of a two-way analysis of variance with Tukey honestly significant difference tests (alpha= .05). They found that specimens cleaned with Sikko Tim and Consepsis Scrub had higher shear bond strength values than did those in the no-treatment control group or the group cleaned with Cavity Cleanser. The specimens treated with the total-etching adhesive system had higher shear bond strength than did those treated with the self-etching adhesive systems. CONCLUSIONS: Sikko Tim and Consepsis Scrub were effective in removing provisional cement. Adhesive resin cement showed higher bond strength when used in conjunction with the total-etching adhesive system. CLINICAL IMPLICATIONS: The use of an effective dentin cleaner before cementation with resin cement can increase bond strength.     

Clinical application of a fiber-reinforced post system

The tooth structure of an endodontically treated tooth was restored with a core on a post, both prefabricated with fiber-reinforced polymer-ceramic material (Sculpture/FibreKor) and subsequently with a metal-free crown. The tooth restoration is described in detail. It includes root canal preparation, polyvinyl siloxane impression taking, laboratory fabrication of the core on the post, adhesive cementation of the post-and-core system in the root canal, fabrication and cementation of the restorations, adjustment, and finishing. The success of this metal-free system is based on its increased flexural and tensile strength. Its application is safe, effective, and reliable. The high-quality aesthetics of the restorations is due to the translucency of the post-and-core material.     

Flexure strength evaluation of a laboratory-processed fiber-reinforced composite resin

STATEMENT OF PROBLEM: A fiber-reinforced composite resin system has been introduced for posterior restorations; however, little information is known regarding possible degradation of its flexure strength with respect to aging and cyclic loading. PURPOSE: The aim of this in vitro study was to determine whether the fiber reinforcement improved the flexure strength of an indirect composite resin aged in air and water for 3 months and then subjected to static and cyclic loading. MATERIAL AND METHODS: The materials tested in this study, non-fiber-reinforced composite resin (n=160) (Tescera Dentin) and fiber-reinforced composite resin (n=160) (Tescera U-beam and Rod), were fabricated as bars, 25.0 x 4.5 x 4.5 mm, and polished with 120- to 320-grit silicon carbide grinding paper. The static (n=15) and cyclical (n=25) flexure strengths (MPa) of specimens were tested initially and after 3 months' aging in air and water. The specimens were tested in 3-point loading in their respective aging media at a loading rate of 2 mm/min. Cyclic testing followed the staircase approach of either 1000 cycles or until specimen fracture. Statistical analysis for the static-loaded specimens consisted of a 3-way analysis of variance (media, aging, and fiber-reinforced versus unreinforced) (alpha=.05), whereas the cyclic-loaded specimens used confidence levels of .95 for the respective variables (media, aging, and fiber-reinforced versus unreinforced) and to compare static versus cyclic loading. RESULTS: The statistical analysis of the static specimens showed no significant difference between control (unaged) groups and aged groups and aging media, but a significant difference (P<.001) between reinforced versus unreinforced specimens. For the cyclic-loaded specimens, the confidence levels at .95 showed no difference between control (unaged) groups and aged groups and aging media (air or water), but a difference between reinforced versus unreinforced specimens, and static-loaded versus cyclic-loaded specimens. During testing, the specimens separated into several pieces when the fiber reinforcement was on the compressive side, whereas the specimen remained intact when the fiber reinforcement was on the tensile side. CONCLUSIONS: When compared to indirect composite resin without fiber reinforcement, the addition of fibers is an effective method to improve the flexure strength of indirect composite resin for the materials tested.     

实验双固化树脂水门汀粘接强度的评价

目的:评价研制的EAM基双固化树脂水门汀在根管内与纤维桩的粘接强度.方法:利用微推出实验方法测试研制的EAM基双固化树脂水门汀在根管内(冠方1/2与根方1/2)与纤维桩的粘接强度,并与2 种商品的双固化树脂水门汀Clearfil DC Core、 LuxaCore-Dual进行对比.结果: 3种树脂水门汀冠方1/2与根方1/2的粘接强度分别为:新研制EAM基树脂水门汀 (11.78±3.36)MPa、(7.58±1.74) MPa,Clearfil DC Core (14.24±3.92)MPa、(8.79±2.93) MPa, LuxaCore-Dual (11.25±2.56)MPa、(5.78±1.95) MPa, 统计分析显示:冠方1/2部分的粘接强度EAM基双固化树脂水门汀与LuxaCore-Dual间无显著差异(P＞0.05),两者均低于Cleafil DC Core(P＜0.05);根方1/2部分的粘接强度EAM基双固化树脂水门汀与Cleafil DC Core间无显著差异(P＞0.05),两者均高于LuxaCore-Dual(P＜0.05).结论: 新研制的EAM基双固化树脂水门汀具有一定的粘接强度,达到了部分同类商品的性能.     

Microleakage of a self-adhesive resin cement after post cementation

The aim of this study is to evaluate the microleakage a self-adhesive cement recently marketed Rely X U100 (3M ESPE). Thirty roots of bovine teeth with 14 mm long were restored with self-adhesive cement and Glassix fiber post DC3 (FGM). Roots were randomly divided into three groups (n=10) according to the technique of placement of the cementing agent: G1 - Centrix syringe; G2 - Lentulo drill and G3 - Manual technical. After cementation, provisional restorations were fabricated with composite resin (Opallis/FGM) without the use adhesive system. After they were finished, polished and thermo cycled by 1000 cycles, in water at temperature of 5 degrees C and 55 degrees C, 30 seconds in each bath. For microleakage test each group of roots was immersed in recipients with Rodhamine B dye solution buffered at 2%, during 24 hours. After this time, the samples were washed in tap water, sectioned and evaluation of dye leakage. The values of infiltration were obtained by the qualitative method (scoring) and statistical analysis using Kruskal-Wallis test and also by the quantitative method (Image Tool) and statistical analysis using ANOVA one way. For both tests, no significant difference between the techniques of placement of the self-adhesive cement. Based on these findings, micro-infiltration was present in all groups, and the placement technique did not influence the degree of micro-leakage, both for the qualitative analysis as to the quantitative.     

Effect of a ZOE temporary cement on the bond strength of a resin luting cement

This study was conducted to determine if a eugenol-based temporary cement affected the bond strength of a dual-cure cement to etched enamel. Dicor buttons were cemented to etched enamel surfaces after pretreatment with a non-eugenol containing cement, a eugenol containing cement and a control. This study concluded that shear bond strengths were unaffected by the temporary cement, provided the enamel surface was cleaned with pumice and etched with 37% phosphoric acid.     

Effects of different surface pre-treatments on the bond strength of adhesive resin cement to quartz fiber post

Abstract Objective. The purpose of this study was to evaluate the effect of mechanical and chemical surface treatment methods on the bond strength of resin cement to fiber post. Materials and methods. The roots of 36 maxillary central incisor teeth were mounted in auto polymerized acrylic resin blocks (10 × 15 mm) and the root canals were enlarged with the drills of post system (2.1 mm width, 12 mm length). Thirty-six fiber posts were randomly assigned to one of the following surface conditioning methods: silane coupling agent, methylene chloride etching, 24% hydrogen peroxide etching, air abrasion with 50 μm Al(2)O(3), 1-3 μm synthetic diamond particles and silica coating with 30 μm SiO(x). Fiber posts were cemented to the root canals with adhesive resin cement (Panavia F 2.0). Three slices of 1.5 mm thick were obtained from each root. Push-out tests were performed with a universal testing machine. The data were analyzed with one-way analysis of variance (ANOVA) and Tukey HSD tests (α = 0.05). The effect of the surface treatments were examined under a scanning electron microscope (SEM) and surface roughness were evaluated with a profilometer. Results. Surface pre-treatment methods affected the bond strength (p < 0.05). The highest bond strengths were obtained by air abrasion with synthetic diamond particles, the lowest bond strength were obtained by etching with methylene chloride (p < 0.05). Conclusion. Mechanical surface pre-treatment methods showed higher bond strength values than chemical methods. Synthetic diamond particles may be an alternative method to increase resin cement bonding on the quartz fiber post surfaces.     

Effects of different surface pre-treatments on the bond strength of adhesive resin cement to quartz fiber post

Abstract

Objective. The purpose of this study was to evaluate the effect of mechanical and chemical surface treatment methods on the bond strength of resin cement to fiber post. Materials and methods. The roots of 36 maxillary central incisor teeth were mounted in auto polymerized acrylic resin blocks (10 × 15 mm) and the root canals were enlarged with the drills of post system (2.1 mm width, 12 mm length). Thirty-six fiber posts were randomly assigned to one of the following surface conditioning methods: silane coupling agent, methylene chloride etching, 24% hydrogen peroxide etching, air abrasion with 50 µm Al₂O₃, 1–3 µm synthetic diamond particles and silica coating with 30 µm SiO_x. Fiber posts were cemented to the root canals with adhesive resin cement (Panavia F 2.0). Three slices of 1.5 mm thick were obtained from each root. Push-out tests were performed with a universal testing machine. The data were analyzed with one-way analysis of variance (ANOVA) and Tukey HSD tests (α = 0.05). The effect of the surface treatments were examined under a scanning electron microscope (SEM) and surface roughness were evaluated with a profilometer. Results. Surface pre-treatment methods affected the bond strength (p < 0.05). The highest bond strengths were obtained by air abrasion with synthetic diamond particles, the lowest bond strength were obtained by etching with methylene chloride (p < 0.05). Conclusion. Mechanical surface pre-treatment methods showed higher bond strength values than chemical methods. Synthetic diamond particles may be an alternative method to increase resin cement bonding on the quartz fiber post surfaces.