Microshear Bond Strength Of Resin Research Articles

Comparison of the Micro-Shear Bond Strength of Resin Cements to CAD/CAM Glass Ceramics with Various Surface Treatments.

This study aimed to compare the effect of acid etching, sandblasting, or silica coating on the micro-shear bond strength of dual-cured resin cements to computer-aided design and computer-aided manufacturing (CAD/CAM) glass ceramic materials. Feldspathic, lithium disilicate, and zirconia-reinforced CAD/CAM ceramics were divided into four groups: control group (C), no surface treatment; hydrofluoric (HF) group, 5% HF acid-etched; sandblasting (SB) group, abraded with 50 µm aluminum oxide (Al2O3) particles; silica-coated (CJ) group, abraded with 30 µm silica-modified Al2O3 particles. Roughness values were obtained by using a profilometer. The cements were condensed on the surface-treated specimens and a micro-shear bond test was conducted. The ceramic material (p < 0.001) and surface treatment type (p < 0.001) significantly affected the micro-shear bond strength values. HF acid etching can be recommended for the surface pretreatment of feldspathic, lithium disilicate, and zirconia-reinforced CAD/CAM ceramics. Better bond strengths can be obtained with HF acid etching than with sandblasting and silica coating.

Effect of Dentine Pretreatment with 38% Silver Diamine Fluoride and CPP-ACPF on Micro-Shear Bond Strength of Resin Modified Glass Ionomer Cement

The aim of the study is to evaluate the micro-shear bond strength and mode of failure of resin modified glass ionomer cement (RMGIC) placed on demineralized dentin pre-treated with 38% silver diamine fluoride (SDF) and casein phosphopeptide amorphous calcium phosphate (CPP-ACP). In order to mount the premolars in acrylic blocks, 30 caries-free human premolars were divided mesio-distally into two equal halves.. Then the enamel was removed to expose the dentin and immersed in demineralizing solution for 96 h, which were then randomly allocated into three groups: Group-1: pretreatment with 38% SDF + RMGIC; Group-2: pretreatment with CPP-ACPF + RMGIC; and Group-3: No pretreatment + RMGIC (control). After the pre-treatment, resin modified glass ionomer cement was placed over the dentin surface using cylindrical mold. Then the micro-shear bond strength was evaluated using universal testing machine and mode of fracture was analyzed with stereomicroscopy. The micro-shear bond strength was found to be higher for the control group (35.73 ± 4.15) followed by SDF (28.39 ± 1.64) and CPP-ACPF (23.00 ± 2.17) and this difference was found to be statistically significant (p = 0.001). On analyzing the mode of failure, the adhesive type of failure was most common in all the groups and the difference in the percentages of mode of failure between the groups was not significant (p = 0.337). Application of 38% SDF and CPP-ACPF on demineralized dentin samples has shown to reduce the micro-shear bond strength of resin modified glass ionomer cement. Adhesive failures were the most common type of failures in both pretreated and untreated groups.

The micro-shear bond strength of resin cements to aged laser bleached enamel after using different desensitizing agents.

ObjectivesTo evaluate the micro‐shear bond strength of two resin cements to aged laser bleached enamel after the application of three different desensitizing agents.Materials and methodsForty extracted human central and lateral incisors were prepared and bleached using laser activation bleaching protocol. The teeth were assigned randomly into four groups for desensitization; G1: No post‐bleaching treatment, G2: GC MI Paste Plus, G3: Hydroxyapatite nanoparticles (n‐HAP) and G4: Flor‐Opal. Specimens were subjected to aging for 6 months. All groups were subdivided into two subgroups according to the resin cements used (dual‐curing resin cement and light‐curing resin cement).ResultsFlor‐Opal groups showed the highest statistically significant micro‐shear bond strength (MSBS), followed by GC MI Paste Plus and n‐HAP groups with no statistically significant difference between them. The light‐curing resin cement had statistically higher MSBS than dual‐curing resin cement in case of no‐post bleaching treatment and n‐HAP groups, and no statistical difference in case of GC MI Paste Plus and Flor‐Opal groups.ConclusionUsage of desensitizing agents containing, CPP‐ACP, n‐HAP or fluoride after laser bleaching can enhance the bond strength of the resin cements to enamel.Clinical significanceThe composition of the desensitizing agents applied after laser bleaching could interfere in bond strength values.

Micro-shear bond strength of resin cements to Er,Cr:YSGG laser and/or acid etched enamel

The purpose of this study was to evaluate the effect of Er,Cr:YSGG laser irradiation and/or acid etching on the micro-shear bond strength (µSBS) of two different dual-cured resin cements to human enamel. 24 intact, extracted molars were sectioned longitudinally and randomly divided into three subgroups according to three surface pretreatment methods:(1) Er,Cr:YSGG laser (Waterlase MD, Biolase) irradiation was used with a power setting of 2 W (55% water and 65% air), and a repetition rate of 20 Hz for 10 s;(2) 37% phosphoric acid application for 20 s;(3) Re-etching with phosphoric acid for 20 s after the Er,Cr:YSGG laser irradiation as in group1.12 enamel discs for each of the resin cements (Panavia F2.0 and Variolink N) were prepared and three cylinders of resin cements were bonded to each enamel surface (n = 12). A micro-shear bond test (EZ-test- 500 N) was used at a cross-head speed of 1 mm min−1 to determine the µSBS. One-way analysis of the variance and Tukey post-hoc tests at the 95% confidence level were used to analyze the µSBS values. Panavia F2.0 verified significantly higher µSBS values than Variolink N (p < 0.05) for all the tested surface pretreatment methods. The combination of laser and acid etching on enamel produced higher µSBS values for bonding both resin cements than the use of acid or laser irradiation alone. The combination of the Er,Cr:YSGG laser and phosphoric acid etching of the enamel for the cementation of indirect restorations with Variolink N and Panavia F2.0 produced better µSBS values to enamel than the use of phosphoric acid or Er,Cr:YSGG laser etching alone, holding the potential to become a highly attractive method for routine use.

Bond Strength of Resin Cements to Zirconia Ceramic Using Adhesive Primers.

To evaluate the influence of adhesive primers on the microshear bond strength of resin cements to zirconia ceramic. Fifty zirconia plates (12 mm × 5 mm × 1.5 mm thick) of a commercially available zirconium oxide ceramic (ZirCad) were sintered, sandblasted with aluminum oxide particles, and cleaned ultrasonically before bonding. The plates were randomly divided into five groups of 10. Three resin cements were selected (RelyX ARC, Multilink Automix, Clearfil SA Cement self-adhesive resin cement), along with two primers (Metal-Zirconia Primer, Alloy Primer) and one control group. The primers and resin cements were used according to manufacturers' recommendations. The control group comprised the conventional resin cement (RelyX ARC) without adhesive primer. Test cylinders (0.75 mm diameter × 1 mm high) were formed on zirconia surfaces by filling cylindrical Tygon tube molds with resin cement. The specimens were stored in distilled water for 24 hours at 37°C, then tested for shear strength on a Shimadzu EZ Test testing machine at 0.5 mm/min. Bond strength data were analyzed statistically by two-way ANOVA and Dunnett's test (5%). The bond strength means in MPa (± s.d.) were: RelyX ARC: 28.1 (6.6); Multilink Automix: 37.6 (4.5); Multilink Automix + Metal-Zirconia Primer: 55.7 (4.0); Clearfil SA Cement: 46.2 (3.3); and Clearfil SA Cement + Alloy Primer: 47.0 (4.1). Metal-Zirconia Primer increased the bond strength of Multilink Automix resin cement to zirconia, but no effect was observed for Alloy Primer using Clearfil SA Cement. RelyX ARC showed the lowest bond strength to zirconia.

Effect of water storage on bond strength of self-adhesive resin cements to zirconium oxide ceramic.

To evaluate the microshear bond strength of resin cements to yttrium-stabilized tetragonal zirconium oxide surfaces after water storage for 24 h or 1 year. Four self-adhesive (BisCem, G-Cem, RelyX Unicem, SeT) and one conventional resin cement (RelyX ARC) were tested. The materials were mixed and inserted in tubes (0.75 mm diameter × 1 mm height) that were placed over the zirconium oxide surface. Specimens were tested after 24-h or 1-year water storage. Microshear testing was performed using a universal testing machine. Shear bond strength results were analyzed using two-way ANOVA and Tukey's test (5%). After 24-h water storage, no difference was found between G-Cem and RelyX Unicem resin cements; however, their bond strength means to zirconium oxide were statistically higher than RelyX ARC. The bond strength values of all resin cements dropped significantly after 1 year of water storage. G-Cem presented the highest values among cements after long-term water exposure. One-year water storage decreased the microshear bond strengths to zirconium oxide for all resin cements tested.

Evaluation of micro-shear bond strength of resin modified glass-ionomer to composite resins using various bonding systems

Aim:The aim was to compare the micro-shear bond strength between composite and resin-modified glass-ionomer (RMGI) by different adhesive systems.Materials and Methods:A total of 16 discs of RMGI with a diameter of 15 mm and a thickness of 2 mm were randomly divided into four groups (n = 4). Four cylinders of composite resin (z250) were bonded to the RMGI discs with Single Bond, Clearfil SE Bond and Clearfil S3 Bond in Groups 1-3, respectively. The fourth group was the control. Samples were tested by a mechanical testing machine with a strain rate of 0.5 mm/min. Failure mode was assessed under a stereo-microscope.Results:The means of micro-shear bond strength values for Groups 1-4 were 14.45, 23.49, 16.23 and 5.46 MPa, respectively. Using a bonding agent significantly increased micro-shear bond strength (P = 0.0001).Conclusion:Micro-shear bond strength of RMGI to composite increased significantly with the use of adhesive resin. The bond strength of RMGI to composite resin could vary depending upon the type of adhesive system used.