Evaluation Of Bond Strength Research Articles

Effects of Hydrofluoric Acid Concentrations, Commercial Brands, and Adhesive Application on the Bond Strength of a Resin Luting Agent to Lithium Disilicate Glass Ceramic.

To evaluate the surface topography/roughness and bond strength of a resin luting agent to a lithium disilicate glass ceramic after etching with different concentrations of hydrofluoric acid (HF) and commercial brands. For bond strength evaluation, 260 lithium disilicate glass ceramic (EMX) discs were randomly distributed into 13 groups based on concentrations of HF and commercial brands (n=20): 5% and 10%, Lysanda (LY5 and LY10); 5% and 10%, Maquira (MA5 and MA10); 5% and 10%, FGM (FG5 and FG10); 4.8%, Ivoclar Vivadent (IV5); 5% and 10%, PHS do Brasil (PH5 and PH10); 5% and 10%, BM4 (BM5 and BM10); 9%, Ultradent Inc (UL10); and Dentsply (DE10). A further random distribution (n=10) was made based on the application (+) or absence (-) of an adhesive layer. Resin luting agent cylinders (1 mm in diameter) were added on EMX surfaces, light-cured, and stored for 24 hours in deionized water at 37°C. On a universal testing machine (DL 500, EMIC), specimens were submitted to a microshear bond strength test at a crosshead speed of 1 mm/min until failure. A representative etched EMX disc from each group underwent surface topography analysis using field-emission scanning electron microscopy (n=1), and five (n=5) etched EMX discs from each group were tested for surface roughness. Data were statistically analyzed using analysis of variance and Tukey test (α=0.05). A less conditioned and smoother surface was observed for 5% HF compared to 10%. Additionally, commercial brands of HF were shown to affect bond strength. When the adhesive layer was not used (-), a 10% concentration promoted higher bond strengths to EMX. However, when adhesive was applied (+), the concentrations of HF and commercial brands had no effect on bond strength results. A 10% concentration of HF results in higher bond strength than a 5% concentration. If an adhesive layer is applied, neither this distinction nor the influence of commercial brands is observed.

Effects of surface treatments of bioactive tricalcium silicate-based restorative material on the bond strength to resin composite

ObjectivesThis study aimed to enhance the bond strength between Biodentine™ (BD), a bioactive tricalcium silicate (C3S) based material, and resin composite through various surface treatments. MethodologyBD samples were immersed in either double distilled water or Hank's Balanced Salt Solution and analyzed using X-ray Diffraction (XRD). Shear bond strength (SBS) evaluations of BD were performed using Prime & Bond™ NT (PNT), Single Bond Universal (SBU), Xeno V (Xeno), and glass ionomer cement (GIC) following various etching durations (0 s/ 15 s/ 30 s/ 60 s with 37.5% phosphoric acid). Two primers, RelyX™ Ceramic Primer (RCP) and Monobond ™ Plus (MBP), were chosen to prime BD for SBS enhancement. Fractography and bonding interfaces were examined with energy dispersive X-ray spectroscopy (EDS)/ scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). ResultsXRD confirmed BD’s main compositions as C3S, Ca(OH)2, CaCO3 and ZrO2 after 14 days crystal maturation. Etched BD did not improve SBS. GIC exhibited the lowest SBS (p < 0.05) among all adhesives, regardless of the etching mode (all < 1 MPa). The highest SBS (17.5 ± 3.6 MPa, p < 0.05) was achieved when BD primed with MBP followed by SBU application. FTIR and EDS showed γ-MPTS and10-MDP within the MBP primer interacted with C3S and ZrO2 of BD, achieving enhanced SBS. Most specimens exhibited mixed or cohesive failure modes.SignificanceBD’s subpar mechanical properties and texture may contribute to its poor adhesion to resin composite. Pretreating BD with MBP primer, followed by SBU adhesive is recommended for improving bond strength.

Application of Laser Treatment in Adhesive Bonding of Liners to Polymethyl Methacrylate Denture Resins: A Systematic Review and Meta-Analysis.

Objective: This systematic review and meta-analysis aimed to assess the influence of laser treatment on adhesive bonding of liners to polymethyl methacrylate (PMMA) denture base resins. Methods: The focused question was: "Does the application of laser treatment (Intervention) influence the adhesive bonding strength (Outcome) of liners to PMMA denture base resins (Population) as compared with untreated or unconditioned surfaces (Control)?" In vitro and clinical reports as well as reports on influence of laser treatments on bonding strength of liners to PMMA denture resins in comparison with untreated surfaces were included. Reports without any control group[s], without any application of laser[s] for PMMA denture bases that did not utilize PMMA denture bases, and not evaluate bond strength of PMMA denture base resins were excluded. An electronic search was conducted on PubMed, Scopus, and Web of Science. Meta-analyses were performed for calculating the standard mean difference (SMD) with a 95% confidence interval (95% CI). Results: Nine of the 12 included studies found that laser irradiation treatment produced significant surface texture alterations of the PMMA denture base and improved the adhesion between the PMMA denture base and soft lining. According to the meta-analysis, tensile bond strength showed an SMD of -2.49% (95% CI: -3.89 to -1.08; p = 0.0005), suggesting a statistically significant difference between the control and test groups (i.e., favoring laser-treated samples than untreated samples). Regarding shear bond strength scores, the outcomes showed an SMD of -2.24% (95% CI: -3.79 to -0.69; p = 0.005), suggesting a statistically significant difference between the control and test groups (i.e., favoring laser-treated samples than untreated samples). Conclusions: Despite the high heterogeneity among the included studies, it can be concluded that laser treatment might improve the bonding strengths of liners to PMMA denture base resins as compared with untreated surfaces. To validate the aforementioned conclusions, further verification is required through the implementation of well-designed randomized controlled trials with large sample sizes.

Evaluation of the shear bond strength of various adhesives on the surface of enamel irradiated with various doses of radiotherapy

We aimed to compare the shear bond strength (SBS) forces on the enamel surface with 2 adhesives after treatment with various radiation doses. A total of 120 premolars were included in the study. The teeth were randomly divided into 5 main groups (n= 24): negative control (without aging), positive control (with aging), 40 Gy, 60 Gy, and 70 Gy radiation. The 40 Gy, 60 Gy, and 70 Gy groups underwent conventional radiotherapy 5 days a week with a dose of 2 Gy each day. After the radiotherapy, all samples except the negative control group were subjected to thermal cycle aging. In all 5 groups, the specimens were divided into 2 subgroups, and half were bonded using 2 adhesives. After bonding, the universal Shimadzu test device was used to analyze the SBS. After the test, the tooth surfaces were examined under a stereomicroscope to determine the adhesive remnant index. When adhesives were compared, Biofix adhesive's bond strength value was statistically higher in the 40 Gy group than in the Transbond XT group (P= 0.001). The SBS value was higher in all irradiated groups than in nonirradiated groups (P= 0.001). When the adhesive remnant index score was analyzed, no significant difference was found among the groups. The SBS increased in irradiated teeth compared with unirradiated teeth, and the SBS values of both adhesives were within the acceptable limits in all radiation groups.

Investigation on bonding between aggregates and asphalt binder containing warm mix additives

Increased moisture susceptibility has been identified as one of the potential failures for warm-mix asphalt (WMA). In order to critically understand the moisture damage mechanism, the evaluation of bond strength between aggregate and asphalt binder holds significant importance. The bonding mechanism can be easily explained by Pneumatic Adhesion Test (PAT). This study evaluated the bond between various aggregates and warm mix (WM) modified asphalt binders using PAT. Five aggregates, two base binders, and four WM additives with varying dosages have been selected for the present experimental study. The objective is to identify the relative contribution of these factors towards the development of bond strength and their consequence against moisture damage. Bond strength was evaluated in terms of the pull-off tensile strength (POTS), whereas moisture susceptibility was determined using the bond strength ratio (BSR) parameter. Results showed that the bonding between aggregate and asphalt binder relies on the aggregate type, base binder, WM additives and their dosages. Since PAT was carried out on both wet and dry-conditioned samples, it was found that the conditioning state (wet and dry) also affects the interfacial bonding of the asphalt-aggregate matrix. Wet-conditioned samples tend to exhibit lower POTS values than dry-conditioned samples. The BSR values were found to be different for various aggregate-asphalt binder combinations. The minimum BSR was found to be 0.82 for a moisture-resistant asphalt mixture.

Comparative Evaluation of Tensile Bond Strength of Two Soft Liners Bonded to Heat-Cured and 3D-Printed Denture Base Materials

Comparative Evaluation of Tensile Bond Strength of Two Soft Liners Bonded to Heat-Cured and 3D-Printed Denture Base Materials

Evaluation of Glass Ceramic Bond Strength to Different Foundation materials

Evaluation of Glass Ceramic Bond Strength to Different Foundation materials

Evaluation of Microtensile Bond Strength between SMART Technique and Conventional Glass Ionomer Cement-treated Carious Primary Dentin.

Silver diamine fluoride (SDF) solution has been used clinically to prevent and arrest dental caries. To evaluate the microtensile bond strength between silver-modified atraumatic restorative technique (SMART) and glass ionomer cement (GIC) applied to carious primary teeth and also the mode of restoration failure. A total of 40 carious primary molars were equally allocated into test and control groups after sectioning through the middle of the carious lesion. The test specimens were treated with one drop of 38% SDF and the control with deionized water. The samples were stored in artificial saliva for 14 days at 37° C and the dentin surfaces were conditioned and restored with Fuji IX GP Extra. After 24 hours storage in artificial saliva, the specimens were prepared for testing of microtensile bond strength. Paired t-test was used to compare the mean bond strengths. The mode of failure was assessed with a stereomicroscope under 40× magnification. The mean microtensile strength for the test group was 7.39 MPa [standard deviation (SD ± 2.3)] and 7.20 MPa (SD ± 1.98) for the control group (p > 0.05). The most common mode of failure was the mixed failure mode in both groups. Silver diamine fluoride (SDF) does not adversely affect the bond strength between GIC applied to carious dentin. Velagala D, Reddy A, Reddy VN, et al. Evaluation of Microtensile Bond Strength between SMART Technique and Conventional Glass Ionomer Cement-treated Carious Primary Dentin. Int J Clin Pediatr Dent 2023;16(4):582-586.

Evaluation of Bond Strength and Fracture Load of Teeth With Flared Root Canals Restored With Prefabricated, Anatomical, and Computer-aided Design and Computer-aided Manufacturing Fiber Posts.

This study compared the use of anatomical glass fiber posts using bulk-fill composite resin with computer-aided design and computer-aided manufacturing (CAD/CAM) milled glass fiber post in oversized root canals, through bond strength (BS) and fracture resistance (FR) tests (fracture load). A total of 48 mandibular premolars were selected, half of them had their crowns removed at the cemento-enamel junction (CEJ) and the other half were sectioned 2 mm above the CEJ. Subsequently, teeth were endodontically treated. After 1 week, the standard preparation of the canals was carried out, and the roots were divided into three groups (n=16), according to the use of different restorative techniques (control: prefabricated glass fiber post [PFP], direct anatomical glass fiber post [AFP], and CAD/CAM milled glass fiber post [MFP]). After luting procedures using Single Bond Universal and RelyX Ultimate (3M ESPE), for eight teeth in each group, six specimens were obtained (two slices from each root third: cervical, middle, and apical). For the remaining eight roots of each group, standardized preparations for metal-free crowns, milling of 5 mol% yttria-stabilized tetragonal zirconia polycrystalline, cementation of the crowns, and periodontal ligament simulation were performed. Then, for each group, the BS was evaluated through the push-out test, and the FR was evaluated in compression. The data obtained from BS were submitted to two-way analysis of variance (ANOVA; group vs root region) and Tukey (α=0.05) and from FR to one-way ANOVA (group) and Tukey (α=0.05). For the BS test, the MFP group was statistically superior to the PFP group in all root regions and was statistically superior to the AFP group only in the cervical region, being statistically similar in the middle and apical root regions. For the FR test, the MFP group was statistically superior to the PFP and AFP groups. The milled fiber post technique can be a legitimate alternative in the restoration of weakened roots with flared root canals.

Comparative Evaluation of Mechanical Properties and Bond Strength of Glass Ionomer Cement reinforced with three different concentrations of Silver Nanoparticles as against Conventional Glass Ionomer Cement in Primary Teeth.

Introduction: Restorative dental materials are defined as substances that are used to repair, replace, or enhance a patient's teeth. Various materials used in paediatric dentistry are zinc oxide eugenol, glass ionomer cement, resin composite, calcium hydroxide, silver amalgam, giomers etc. GIC is a biocompatible material having a low thermal expansion coefficient and fluoride release property. There are still a few drawbacks of GIC due of their poor mechanical properties therefore addition of Silver Nanoparticles demonstrated improved mechanical and bactericidal capabilities. There hasn't been much study on the quality of the bond contact between silver nanoparticles and dentin, as well as the color's durability. Aim: To evaluate and compare the mechanical properties and bond strength of Glass ionomer cement reinforced with three different concentrations of silver nanoparticle as against conventional glass ionomer cement in primary Teeth. Materials and Method: Silver nanoparticles will be prepared using three chemicals namely, silver nitrate, sodium citrate and tannic acid. Traditional GIC (GC Fuji II, GC Corporation, Tokyo, Japan) will be purchased. Three different concentrations of silver nanoparticles will be prepared i.e., 0.2, 0.4, and 0.6%. The GIC specimens will then be divided into 4 groups: GIC without silver nanoparticles (AgNPs),0.2%,0.4% and 0.6% AgNPs. Mechanical properties will be checked such as compressive, tensile, and bond strength using Universal Testing Machine. Expected Results: GIC reinforced with silver nano particles is expected to have better mechanical strength, less microleakage and wear resistance, greater fracture resistance and adhesive bond strength. Conclusion: GIC reinforced with silver nano particles will be expected to have better mechanical and physical properties than conventional Type II GICs and is expected to be a promising material for restoration in primary teeth.

Evaluation of repair bond strength of a dental CAD/CAM resin composite after surface treatment with two Er,Cr:YSGG laser protocols following artificial aging

The aim of the present study was to evaluate the impact of two Er,Cr:YSGG laser surface treatments on the repair bond strength of a dental CAD/CAM resin composite (Brilliant Crios) after artificial aging. Twenty-four resin-based CAD/CAM blocks were cut and 48 rectangular slabs (3 x 12 x 14 mm) were prepared. Preliminary SEM observations indicated the most favorable laser settings regarding surface modification of the tested restorative material. The CAD/CAM specimens were then divided into 4 groups (n=12) based on their surface pretreatment: no treatment, air abraded with 50-μm Al2O3 particles, and laser irradiated with two different protocols using Er,Cr:YSGG laser with average power 3.5 and 4.5 W, pulse repetition rate 35 and 50 Hz, and pulse energy 100 and 90 mJ, respectively. After surface treatments each group followed a bonding protocol with silane and a flowable resin composite was used to prepare 48 microrods. Half of the microrods of each group were subjected on shear bond strength (SBS) test (chisel-shaped blade, load cell of 500 N, crosshead speed of 1 mm/min) after 24 h, while the other half underwent artificial aging (15,000 cycles, 5-55 °C) and then SBS test. The debonded specimens were examined under an optical microscope to determine the failure mode. All specimens were also evaluated using SEM to assess the surface topography after the treatments. The results showed that SBS significantly decreased after thermocycling in all the experimental groups (p<0.05). Control group presented much lower SBS values than the other groups after both 24 h and thermocycling (p<0.05). The highest values of SBS exhibited air-abrasion group (p<0.05), followed by the two laser groups, which did not differ to each other (p>0.05). The results of the current study indicated that Er,Cr:YSGG laser irradiation can be an alternative treatment for repairing the tested resin-based CAD/CAM restorative material.

Cyclic shear fatigue of orthodontic brackets bonded to enamel using self-adhering flowable composites

BackgroundSelf-adhering composites are claimed to bond to teeth without prior acid etching and bonding steps. This study aimed to evaluate the cyclic shear fatigue (CSF) of metal orthodontic brackets bonded to enamel using self-adhering flowable composites (Constic and VertiseTM Flow) in comparison with that of total-etch and self-etch adhesives. Materials and methodsTwenty-five human premolars comprising 100 surfaces were randomly divided into four groups (n = 25): total-etch, self-etch, Constic, and VertiseTM Flow. A total of 10 surfaces were used per group for baseline static shear bond strength (SSBS) evaluation and 15 surfaces for CSF evaluation. Each tooth was treated with the four bonding agents. Both SSBS and CSF were evaluated using a universal testing machine. For CSF, the staircase method was used with an initial pulling load equivalent to 60% of the SSBS of each group for 1000 cycles or until failure. The adhesive remaining index (ARI) was evaluated for surviving samples using a stereomicroscope. Statistical analysisA one-way ANOVA with Tukey’s post hoc test was used to analyze the CSF data, and a chi-square test was used to analyze the ARI. ResultsThe total-etch adhesive showed significantly higher CSF values than that of the other groups (p < 0.001). Both total-etch (10.78 ± 0.31 MPa) and self-etch (6.75 ± 0.91 MPa) adhesives showed significantly higher CSF than did Constic (1.94 ± 0.31 MPa) and VertiseTM Flow (2.01 ± 0.25 MPa), (p < 0.001). The ARI indicated that more resin remnants were observed with the total-etch and self-etch adhesives than those with the self-adhering flowable composites. However, no significant differences were observed among groups (p > 0.05). ConclusionsTotal-etch and self-etch adhesives showed satisfactory bond strengths for orthodontic treatment. However, Constic and VertiseTM Flow self-adhering flowable composites may not be clinically sufficient for bonding metallic orthodontic brackets to enamel.

Evaluation of the push-out bond strength of an adjustable fiberglass post system to an endodontically treated oval root canal.

To evaluate the push-out bond strength of the adjustable fiberglass post system to dentin. Twenty maxillary canine roots were endodontically treated and divided into two groups (n=10): conventional fiberglass posts (CFPs) and with single adjustable post (SAP) system. Two slices of each third were subjected to the push-out and failure pattern test and the most apical slice was subjected to analysis of the adhesive interface by scanning electron microscopy (SEM). Data were analyzed by the three-way analysis of variance, Tukey, and Friedman tests, and linear regression (α=0.05). The results showed higher push-out bond strength in the initial time interval for SAP (10.3±5.3, p<0.01). After 6 months, there was reduction in push-out bond strength for both (p<0.001). A higher percentage of adhesive and cohesive failures to dentin. After 6 months areas of maladaptation were noted (p=0.000). The SAP is completed to the promissory root canal in relation to alternative CFP.

Development of LaSAT and bonding strength evaluation of epoxy adhesive over a wide range of loading rates

ABSTRACT This study improved laser shock-wave adhesion test (LaSAT) to evaluate the bonding strength of an aluminum alloy/epoxy resin adhesive, since the bonding strength is dependent on loading rate. In this method, strong shock wave due to laser ablation induces interfacial fracture, and the critical stress is computed using numerical simulations of the FEM. To accurately evaluate the bonding strength, the input waveform caused by laser ablation was identified for FEM computation. Such ablation impact (pressure vs. time) and its spatial distribution of ablation impact were experimentally investigated, and this study computed stress-wave propagation in the specimen. It is found that numerical simulation with FEM reproduced well the wave propagation. A wide range of loading rates was achieved by the quasi-static tensile test, split Hopkinson pressure bar (SHPB) test, and LaSAT. As a result, bonding strength exhibited a significant dependence on the strain rate, similar to that of bulk resin materials in general.

Bond Strength of Orthodontic Brackets to Temporary Crowns: In vitro Effects of Surface Treatment.

To evaluate bond strength of orthodontic brackets to temporary crowns. A bis-acrylic composite was used to create a total of 25 discs, which were then divided into five groups based on how their surfaces were treated with black, blue, green, and sandblasted diamond burs, in addition to a control group. Software called SPSS was used to analyze the outcome. The average pressures measured for the green bur, black bur, and sandblasting, respectively, were 12.05 MPa, 12.87 MPa, and 19.25 MPa. Comparing the control and blue groups, a substantial variation in shear bond strength was only noticed with reference to sandblasting. The binding strength of orthodontic brackets is increased by sandblasting temporary crowns.

Comparative evaluation of shear bond strength of three different glass ionomer cement (conventional, zirconium-reinforced and advanced glass hybrid) in primary molars: an in vitro study.

The success of restorative materials is largely dependent on their capacity to adhere to the tooth structure and withstand the various forces present in the oral cavity. So, the aim of present study was to evaluate and compare the shear bond strength (SBS) of Type IX Glass Ionomer Cement (GIC), Zirconomer, and Gold Label Hybrid GIC in primary molars. Thirty primary molars were selected based on inclusion and exclusion criteria. The molars were polished to provide a flat dentin surface after being inserted in auto polymerizing acrylic resin. The samples were randomly divided into three groups, equally and were bonded to GIC. On the dentin surface, restoration cylinders were made using a plastic mould that had an internal diameter and height of 5mm and 3mm, respectively. The cement was manipulated according to the manufacturer's directions through the plastic mould. Then, the samples were stored at room temperature for 10days to mimic oral conditions. The Universal Testing Machine was used to test SBS. One-way ANOVA and the post hoc Tukey test were used to statistically assess the collected data. A statistically significant difference was found in all three groups (p < 0.01), with Zirconomer demonstrating highest SBS, followed by Type IX GIC and Gold Label Hybrid GIC. The SBS value of Zirconomer was better when compared to Type IX GIC and Gold Label Hybrid GIC.

A Study on Evaluation Methods of Conserving Painted Sculpture

A lot of individual research on materials and methods suitable for the color of the paint layer has been conducted in the conservation of existing painted sculptures. However, there was no guidance standard for conservation treatment and repainting of painted sculptures, and an evaluation method for objective conservation management was required as deterioration continued in the outdoors. Therefore, in this study, the conservation treatment effect was confirmed by comparing and evaluating the physical properties of the original paint and the replacement paint by citing two cases. Based on the survey items : SEM observation (a cross-section and surface defect) and local EDS analysis, comparison of chromaticity and color difference, evaluation of adhesion and adhesive bond strength, and a salt spray test, a condition status table was prepared and applied to the specimen. Based on the results of applying the completed condition status table in the future, it is judged that it can be an objective data onto conservation treatment of outdoor painted sculptures and public artworks.

Realistic Evaluation of Reinforcement Bond Strength in Alkali-Activated Slag Concrete Exposed to Elevated Temperature

Alkali-activated concrete (AAC) has attained great popularity since finding it as an alternative to Portland cement concrete due to its superior characteristics in terms of mechanical properties and durability, and its low negative environmental impact. This research investigated both experimentally and analytically the bond behavior between alkali-activated slag concrete (AASC) and steel rebars considering some important parameters (rebar diameter and development length-to-diameter ratio) before and after exposure to elevated temperature using beam-end bond testing technique. The obtained experimental results were compared with those obtained from applying the CEB-FIP model and the well-known available equations in the literature. A modified model was proposed for predicting the bond behavior of AASC. Results have showed that the CEB-FIP model provides more conservative values for bond strength compared to the experimentally obtained results which increases the safety level when estimating the bond strength for design purposes. The proposed modified model achieved a higher correlation with the experimental results than the CEB-FIP model at ambient temperature.

Use of final irrigants MTAD, Salvedora Perscia, Malachite green, and Ti-sapphire laser on push-out bond strength of Zirconia post

AIM: Evaluation of the push-out bond strength (PBS) of zirconia post-bonded to radicular dentin after using different final irrigants (MTAD, Malachite green (MG), Ti-sapphire laser and Salvadora persica (S.persica). MATERIAL AND METHOD: Forty human permanent single-rooted were decoronated above the cement-enamel junction. An experienced endodontist performed all the root canal instrumentation using ProTaper universal rotary files. Canals were irrigated using 5.25% NaOCl solution followed by EDTA as a final sterilant. Obturation with gutta-percha using AH Plus sealer was performed. Post-space preparation was completed using Gates Glidden and specimens were randomly assigned to four groups based on the final disinfectant received (n=10). Group 1: 5.25% NaOCl + MTAD, group 2: 5.25% NaOCl + MG, group 3: 5.25% NaOCl +Ti-sapphire laser, and group 4: 5.25% NaOCl + S. persica. The chemically polymerized resin was used to lute zirconia posts. PBS and failure mode analysis were performed using a universal testing machine and stereomicroscope at 40X magnification. Data were compared between the two groups with 95% CI using one-way analysis of variance (ANOVA) with the Tukey post hoc test. p=0.05. RESULTS: Group4(5.25% NaOCl+ S.persica) specimens demonstrated the maximum (8.94±0.14 MPa) bond strength. Conversely, the apical third of Group 2 (5.25% NaOCl+ MG) (2.87±0.15 MPa) samples revealed the minimum bond strength scores. Intergroup comparison exposed that Group 1 (1.3% NaOCl+ MTAD), Group 3 (5.25% NaOCl+Ti-sapphire laser), and Group 4 (5.25% NaOCl+ S. persica) at all three-thirds unveiled no significant difference in PBS (p<0.05). CONCLUSION: Ti-sapphire laser and Salvedora Persica possess the potential to be used as a final root canal irrigant to improve the push-out bond strength of zirconia post-to-root dentin.

Evaluation of Bond (Adhesive) Strength Between Conventional Concrete and Steel Fiber Reinforced Concrete Interface

Good bond strength between overlay and substrate is a key factor in performance of concrete repairs. This thesis was aimed at studying the evaluation of bond strength between conventional concrete substrate and steel fiber reinforced concrete. Many factors such as surface roughness, existence of micro cracks, compaction, curing etc. influence `the bond strength. The quality assurance of the bond strength requires test methods that can quantify the bond strength as well as identify the failure mode. There have been numerous investigations led to development of different test methods. The forces which are applied in each test and the failure mode are important in order to choose the proper test. An interpretive study on test methods is presented. While this study can provide individually useful information on bond strength and bond characterization.