Microtensile Bond Strength Evaluation Research Articles

Assessment of physical properties of bioactive glass-modified universal multimode adhesive and its bonding potential to artificially induced caries affected dentin

BackgroundTo evaluate the physical properties of bioactive glass-modified universal multimode adhesive and its micro-tensile bond strength (µTBS) to artificially induced caries-affected dentin.MethodsAll bond universal adhesive was used in the study. Specimens were divided into 2 main groups: control unmodified adhesive and 5 wt% BAG modified adhesive. The degree of conversion, pH, bioactivity, and viscosity of the adhesives were tested with n = 5 for each test. Micro-tensile bond strength evaluation was done in etch & rinse (ER) and selective-etch (SE) modes, where 24 human molar teeth were used (n = 3), 12 teeth for immediate bond strength, and the other 12 were tested after 6 months of storage in simulated body fluid (SBF).ResultsNo significant difference was found between the control and the 5wt% BAG groups regarding the degree of conversion (61.01 ± 0.43 and 60.44 ± 0.61 respectively) and the viscosity (109.77 ± 22.3 and 124.3 ± 9.92 respectively). The control group revealed significantly lower pH values than the 5wt% BAG group (3.16 ± 0.5 and 4.26 ± 0.09 respectively). Immediate bond strength results revealed that the 5wt% BAG in the ER mode had the highest bond strength followed by the control group in the ER mode (44.16 ± 7.53 and 44.00 ± 7.96 respectively). SE groups showed that the immediate strength of the 5wt% BAG group was higher than the control group (42.09 ± 6.02 and 39.29 ± 6.64 respectively). After 6 months of storage, bond strength results revealed a decrease in bond strength values for the control groups but not for the 5wt% BAG in both application modes.ConclusionsThe incorporation of BAG (5wt%) improved the universal adhesive micro-tensile bond strength and bond durability for both adhesive application modes without affecting its degree of conversion or viscosity.

Effect of Nisin-based pretreatment solution on dentin bond strength, antibacterial property, and MMP activity of the adhesive interface

ObjectiveTo evaluate the effect of a Nisin-based dentin pretreatment solution on microtensile bond strength, antibacterial activity, and matrix metalloproteinase (MMP) activity of the adhesive interface. Materials and methods100 human molars were sectioned to expose dentin. The teeth were assigned to five groups (n = 20), according to the dentin pretreatment: 0.5%, 1.0%, or 1.5% Nisin; 0.12% chlorhexidine (positive control), and no solution (negative control), and divided into 2 subgroups: no aging, and thermomechanical aging. Specimens were etched with 37% H3PO4 for 15 s and submitted to the dentin pretreatment. Then, they were bonded with an adhesive (Adper Single Bond 2) and a resin composite for microtensile bond strength (μTBS) evaluation. Antibacterial activity against Streptococcus mutans was qualitatively examined using an agar diffusion test. Anti-MMP activity within hybrid layers was examined using in-situ zymography. Data were analyzed with two-factor ANOVA and post-hoc Tukey’s test (α = 0.050). ResultsFor μTBS, significant differences were identified for the factors “solutions” (p = 0.002), “aging” (p = 0.017), and interaction of the two factors (p = 0.002). In the absence of aging, higher μTBS was observed for the group 0.5% Nisin. In the presence of aging, all groups showed similar μTBS values. All Nisin concentrations were effective in inhibiting the growth of S. mutans. Endogenous MMP activity was more significantly inhibited using 0.5% and 1.0% Nisin (p < 0.050). Conclusion0.5% and 1.0% Nisin solutions do not adversely affect resin-dentin bond strength and exhibit a potential bactericidal effect against S. mutans. Both concentrations effectively reduce endogenous gelatinolytic activity within the hybrid layer. Clinical relevanceThe use of 0.5% and 1.0% Nisin solutions for dentin pretreatment potentially contributes to preserving the adhesive interface, increasing the longevity of composite restorations.

"No-Primer" Resin Cementation of Lithium Disilicate Ceramic: A Microtensile Bond Strength Evaluation.

The objective of this study was to evaluate the resin-ceramic adhesion of a long-carbon-chain silane (LCSI)-containing resin cement. Polished lithium disilicate ceramic discs were etched with hydrofluoric acid and randomly assigned into four groups; (PSAP), cemented using a silane-free resin cement with no prior priming; (PSAP-S), primed using a silane-containing primer before cementation using a silane-free resin cement; (PSAU), cemented using a LCSI-containing resin cement with no prior priming; (PSAU-S), primed as for the group (PSAP-S) and cemented using a LCSI-containing resin cement. The cemented blocks were sectioned into microbeams. The resin-ceramic microtensile bond strength (μTBS) was measured at 1 week and after thermocycling. The failure modes of the tested microbeams were evaluated. The μTBS of the LCSI-containing and silane-free resin cements, either with or without a prior priming step, did not significantly differ. The adhesion of the LCSI-containing resin cement to lithium disilicate ceramic, either with or without a prior priming step, did not significantly deteriorate after artificial aging. The long-carbon-chain silane (LCSI) monomer incorporated in the resin cement eliminated the need for a silane priming step of a hydrofluoric acid-etched lithium disilicate ceramic.

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 Micro-Tensile Bond Strength of A New Resin Composite Restorative Material at Two Different Dentin Depth After Aging (An In-Vitro Study)

Evaluation of Micro-Tensile Bond Strength of A New Resin Composite Restorative Material at Two Different Dentin Depth After Aging (An In-Vitro Study)

Silane-Containing Universal Adhesives Influence Resin-Ceramic Microtensile Bond Strength

Background: Silane-containing universal adhesives (UAs) are marketed as adhesion promotors for glass-ceramics. Objectives: This study aimed to evaluate the priming capacity of γ-methacryloxypropyltrimethoxysilane (γMPTS)-containing and γ-methacryloxypropyltriethoxysilane (γMPTES)/3-(aminopropyl)triethoxysilane (APTES)-containing universal adhesives (UAs) for lithium disilicate ceramic (LDC). Materials and Methods: Etched LDC discs were distributed into four groups according to the priming material used: (control), no priming; (MBN), LDC was primed with a universal primer (Monobond N); (SBU), γMPTS-containing UA (Single Bond Universal Adhesive) was used as a primer; and (SBP), γMPTES/APTES-containing UA (Scotchbond Universal Plus Adhesive) was used as a primer. LDC discs were cemented using a dual-cure resin cement, then sectioned into microbeams for microtensile bond strength (μTBS) evaluation. Failure modes were assessed. Results: MBN application showed the highest μTBS among all groups. γMPTES/APTES-containing UA (SBP) resulted in considerably higher μTBS compared with γMPTS-containing UA (SBU) or the control group. The mixed failures were the most predominant among all groups. Conclusions: The effect of silane-containing UAs on resin-ceramic μTBS is material dependent. Although γMPTES/APTES-containing UA improved bonding to LDC, the priming of LDC with either of the UAs tested cannot be considered as an alternative to a separate silanization (priming) step using a universal primer.

Evaluation of Micro-tensile Bond Strength after Pretreatment of Dentin with Various Natural Bio-modifiers

Evaluation of Micro-tensile Bond Strength after Pretreatment of Dentin with Various Natural Bio-modifiers

Comparative short-time evaluation of microtensile bond strength of modified 8th generation bonding agent to sound and simulated erosive dentin

Comparative short-time evaluation of microtensile bond strength of modified 8th generation bonding agent to sound and simulated erosive dentin

Comparative Evaluation of Microtensile Bond Strength in Three Different Dentin Luting Agents: An In vitro Study.

Long-term clinical success on indirect restorations is largely determined by bonding efficiency of the luting agent, with adhesion to dentin being the main challenge. Therefore, aim of this study was to assess the microtensile bond strength when using flowable resin composite, preheated resin composite and dual self-adhesive resin cement as dentin luting agents. Occlusal thirds of molar teeth were cut and randomly divided into 3 groups to be cemented: RelyX™U200, Filtek™ Z250 XT- preheated to 70° and Filtek Flow™ Z350XT. They were then thermocycled 5000 times between 5+/-2°C and 55+/-2°C. Subsequently, 10 microbars per group were prepared. The 30 samples were placed in saline solution for 24 hours at room temperature prior to microtensile test. This was performed with a digital universal testing machine at a crosshead speed of 0.5 mm/min. The bond strength values obtained were analyzed in Megapascals (MPa). Measures of central tendency such mean and measures of dispersion such standard deviation were used. In addition, the Kruskall Wallis non-parametric test with Bonferroni post hoc test was applied, considering a significance value of 5% (P < 0.05), with type I error. The dentin microtensile bond strengths of preheated resin composite, flowable resin composite and dual self-adhesive cement were 6.08 ± 0.66 Mpa, 5.25 ± 2.60Mpa and 2.82 ± 1.26Mpa, respectively. In addition, the preheated resin composite exhibited significantly higher microtensile bond strength compared to the dual self-adhesive cement (P < 0.001). While the flowable resin composite showed no significant difference with the dual self-adhesive cement (P = 0.054) and the preheated resin composite (P = 0.329). The microtensile bond strength in dentin was significantly higher when using a preheated resin composite at 70°C as a luting agent compared to dual self-adhesive cement. However, the preheated resin composite showed similar microtensile bond strength compared to the flowable resin composite.

A systematic review and meta-analysis of bond strength studies associated with self-etching primer and HF acid etching of dental glass-ceramics

ObjectiveThis review aims to provide a qualitative and quantitative evaluation of the effect of self-etching ceramic primer (SECP) on the resin–ceramic bond strength, as reported in published in-vitro studies. Materials and methodsThree databases (MEDLINE “PubMed”, Scopus and Web-of-Science) were electronically searched to identify studies that evaluated the effect of SECP on the bond strength to glass-ceramics versus the conventional treatment (hydrofluoric acid (HF) etching + silane-primer (S) application). Meta-analysis was conducted with RevMan version 5.4 software, Cochrane Collaboration; Copenhagen, Denmark using a random effect model, considering the bond strength evaluation after artificial aging. ResultsThirty-six studies satisfied the inclusion criteria for qualitative analysis, while only 18 studies were included in the quantitative analysis (meta-analysis). Twenty-three studies (63.9%) of the included studies showed a medium-risk of bias. The meta-analysis results showed no statistically significant difference (p ≥ 0.05) between resin-ceramic bond strength achieved following SECP or HF + S treatment with micro-shear bond strength (μSBS), tensile bond strength (TBS), and micro-tensile bond strength (μTBS) evaluation. However, shear bond strength (SBS) evaluation showed significantly less bond strength of SECP compared with HF + S (p < 0.00001). ConclusionSECP application can effectively promote adequate resin–ceramic bonding despite its mild etching capacity. However, more in-vitro studies that involve long-term clinically relevant artificial aging, and further clinical studies are required before SECP can be considered as an alternative to the conventional surface treatment (HF + S) of glass-ceramic materials.

Evaluation of Micro-Tensile Bond Strength of Fibre Post with Titanium Dioxide Nanoparticles as Fillers in Experimental Dental Composite Resin.

Background: The clinical success of post-core restorations is determined by the composite utilized and the strength of the post-core adhesion. The effectiveness of titanium dioxide nanoparticles (TiO2 NPs) as a multifunctional material with photo-induced activities and better mechanical characteristics are observed as particle size is reduced to under 50 nm. Aim: The purpose of this study is to determine the bond strength of fibre-reinforced composite (FRC) posts with TiO2 NP as fillers and to compare it with conventional composite resin core material. Materials and Methods: 30 single-rooted mandibular premolars were selected and routine root canal procedures were done. A quantity of 5% TiO2 NPs were synthesized and added as silanized filler to the experimental composite resin. Post space was prepared and fibre-reinforced composite (FRC) post luting was performed. The specimens were then grouped into the following groups: Group I consisted of the experimental composite resin containing 5% TiO2 fillers, Group II consisted of core X flow, and Group III consisted of Multicore Flow. All test groups were submitted for thermocycling. After this, the samples were tested for micro tensile bond strength. A stereomicroscope with a magnification of 20× was used to examine the fractured surfaces. The data were analysed using one-way ANOVA and Tukey HSD tests. Results: Statistical analysis revealed that Group I showed the highest mean bond strength value of 35.6180 Mpa. The results obtained with Group III showed the lowest mean bond strength value of 19.4690 Mpa. Adhesive failures were identified by stereomicroscopy of the fractured surfaces. Conclusion: The experimental composite resin comprising 5% TiO2 NP had a greater bond to the FRC post than other materials tested.

Comparative Evaluation of Microtensile Bond Strength of Three Adhesive Systems.

Objectives: The aim of this study was to assess the microtensile bond strength of three universal adhesives to dentin and enamel. Materials and Methods: Sixty extracted human third molar teeth were chosen and divided into six groups regarding the adhesive (G-Premio Bond, Clearfil S3 Bond or Single Bond) and tooth surface. All the applied bonding agents were universal adhesives. The teeth were polished and the adhesives were applied; then the teeth were restored with composite resin. The samples were mounted in acrylic resin and sectioned. The specimens were subjected to a universal testing machine and the microtensile bond strength was measured. The failure mode of each specimen was determined under a stereomicroscope. Data were analyzed using two-way ANOVA (α=0.05). Results: The microtensile bond strength of G-Premio Bond to enamel and dentin was 11.79±8.27 and 17.55±9.47 MPa, respectively which was not significantly different from the values in Single Bond group (15.59±10.66 and 17.19±10.09 MPa to enamel and dentin, respectively; P>0.05). However, the values for Clearfil S3 Bond were 7.11±4.23 and 7.88±8.83 MPa to enamel and dentin, respectively, which were significantly lower than the values for G-Premio Bond (P<0.05). Scanning electron microscopic (SEM) images showed that the adhesive failure was dominant in both enamel and dentin groups and in all adhesive systems. Conclusion: G-Premio Bond and Single Bond provided higher microtensile bond strength compared with Clearfil S3 Bond. Universal adhesives with their acceptable performance can be applied in self-etch mode on both enamel and dentin.

Effect of cementation delay on bonding of self-adhesive resin cement to yttria-stabilized tetragonal zirconia polycrystal ceramic treated with nonthermal argon plasma

Statement of problemNonthermal argon plasma (NTAP) has been reported to improve the bond strength of resin cements to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramics. However, the effect of the inevitable delay before cementation and after treating Y-TZP ceramics with NTAP is unclear. PurposeThe purpose of this in vitro study was to investigate whether delays of 8, 12, and 24 hours between the Y-TZP ceramic treatment with NTAP and the cementation would affect the surface energy and the bond strength of a self-adhesive resin cement to Y-TZP ceramic. Material and methodsSixty plates and 50 blocks of 3Y-TZP ceramic were divided into 2 groups (n=30 and n=25): as-sintered (AS) and airborne-particle abraded with 50-μm Al2O3 (APA). These groups were further divided into 5 subgroups (n=6 and n=5) according to the delay between the NTAP treatment and the measurement of surface energy and microtensile bond strength (μTBS) evaluation: (0, 8, 12, and 24 hours). For both 3Y-TZP surface conditions (AS and APA), a control group without NTAP treatment was used (ASC and APAC). The surface energy (SE) was evaluated with a goniometer and the 3Y-TZP elemental composition with X-ray photoelectron spectroscopy (XPS). For the μTBS test, the 3Y-TZP ceramic blocks were cemented to composite resin blocks with a self-adhesive resin cement. After storage in distilled water at 37 °C for 24 hours, the 3Y-TZP-composite resin blocks were sectioned into beams and submitted to a μTBS test. Data were submitted to 2-way ANOVA and the Tukey HSD test (α=.05). ResultsFor the AS group, NTAP increased the SE irrespective of the delay before measurement: ASC<0 hour=8 hours=12 hours=24 hours (P<.05). For the APA group, except after 12 hours, NTAP also increased the surface energy (P<.05). XPS analysis showed an increase in the oxygen/carbon ratio after NTAP treatment for both groups. For the AS group, NTAP increased the μTBS after 0, 8, and 12 hours (P<.05), whereas for the APA group this occurred only after 8 hours (P<.05). For the AS and APA groups, the highest μTBS was reached after 8 hours (P<.05). ConclusionsTreatment of 3Y-TZP ceramic with NTAP improved the SE and increased the μTBS of self-adhesive resin cement to 3Y-TZP ceramic. These effects were time dependent, with better results at 8 hours after NTAP treatment.

Comparative evaluation of micro-tensile bond strength between zirconia core and all-ceramic layering with different surface treatments: an in vitrostudy

Background: The quest for newer and stronger materials for replacing teeth has resulted in Zirconium oxide's introduction, which possesses excellent mechanical strength and toughness. However, uncertainty exists in the relationship between its bond strength and surface treatment method adopted and the mode of failure at the interface. Aim - The study aimed to evaluate the comparison of micro-tensile bond strength between the zirconia core and all-ceramic layering with different surface treatments and analyse their failure mode by Scanning Electron Microscope (SEM). Materials and methods: Zirconia cores (Ceramill ZI 71 XS) were fabricated by CAD-CAM into discs with 5mm diameter and 3.5mm height. Then the cores were divided into four groups. Among which, Group-I was the control group, and the remaining are surface treated. Group-II specimens were treated with sandblasting, followed by acid etching; Group-III and Group-IV were treated with zirliner and glass beads, respectively. After that, the veneering material (IPS Empress, E.max Ceram Dentin) of 2×2 mm was adhered to the zirconia core and then kept in the ceramic furnace. The specimens were mounted on a Universal Testing Machine, and tensile stress is applied. The obtained data were subjected to One-way ANOVA and Tukey-HSD tests for statistical analyses. Results - The samples treated with sandblasting followed by acid etching showed more micro-tensile bond strength between core and veneer interface. Furthermore, the SEM study revealed a cohesive failure in Group-II, whereas, in Group-I and -III, there was an adhesive failure. Group-IV specimens exhibited a mixed failure. One-way ANOVA showed significant differences (p=0.001) within the groups. In posthoc analysis, Group-III showed significant differences with Groups -I, II, and IV. Conclusion: Increased surface roughness of zirconia obtained by sandblasting with aluminium oxide particles, when coupled along with chemical etching with hydrofluoric acid, enhanced the micro-tensile bond strength between the Y-TZP zirconia core and veneering ceramic.

Evaluation of Microleakage and Microtensile Bond Strength of Two Bulk Fill Composites in Primary Teeth after Caries Removal by Chemomechanical Technique

Aim: Evaluation of microleakage and microtensile bond strength of two bulk fill composites (X-tra fill packable and X-tra base flowable bulk fill composites) in primary teeth after chemomechanical caries removal. Material and methods: Forty extracted human primary posterior teeth with caries not involving pulp exposure were assigned after caries removal by Papacarie into two groups according to restorative material used, each containing 20 teeth. Group 1: was restored with X-tra fill. Group 2: was restored with X-tra base. In two groups Futurabond dual-curing self-etch bond was used to bond restorations to the dentin. Both groups were subdivided into two subgroups: Sub-group A: 10 teeth for microleakage test. Sub-group B: 10 teeth for microtensile bond strength test. For microleakage test: After thermocycling; teeth were covered with varnish then immersed in 2% methylene blue for 24 hours, thereafter the dye penetration was assessed with measured in micrometer using MA100 fully configured Halogen inverted scope. For microtensile test: The samples were sectioned longitudinally to the long axis of the tooth to obtain sticks of standardized cross sectional area. These sticks were stressed to failure under tensile force in a universal testing machine. The µTBs for each specimen was calculated in megapascal. Results: X-tra Fill showed lower insignificant mean microleakage compared to X-tra Base at P value =0.3. X-tra Fill showed higher insignificant mean µTBs (MPa) compared to X-tra Base at P value =0.097. Conclusion: Both bulk fill composites have performed approximately similar regarding microleakage and µTBs after using Papacarie in caries removal.

Comparative Evaluation of Microtensile Bond Strength of Three Restorative Materials

The present study aimed to compare the micro-tensile bond strength of new and conventional glass-ionomers and Z350 flowable composite resin to sound and caries-affected dentin. Eighty extracted third molars were selected. Standard Cl I cavities were prepared on occlusal surfaces. Forty teeth were assigned to the sound tooth group, and in the remaining 40 teeth, carious lesions were produced using a laboratory technique. Then each group (n=40) was subdivided into 5 groups (n=8) in terms of the restorative material used (EQUIA® Forte, Ketac Molar, encapsulated and hand-mixed GC Fuji II LC glass-ionomers and Z350 flowable composite resin). The cavities were restored. The highest micro-tensile bond strength was recorded with Z350 flowable composite resin in sound dentin (29.65), and the lowest was recorded with GC Fuji II LC (powder, liquid) in affected dentin (7.88). Significant differences were detected in the micro-tensile bond strength between the 5 restorative material groups. The composite resin bond strength was the maximum and was significantly different from all the other groups. The micro-tensile bond strength was affected by the type of dentin; in this context, in all the restorative groups, the bond strength in sound dentin was significantly higher than that in affected dentin. The most frequent failure mode was adhesive in the sound and affected dentin.

Effects of calcium-phosphate, laser and adhesive on dentin permeability and bond strength

ObjectivesThe present study examined a technique for reducing dentin permeability through the application of a calcium phosphate (CaP)-based desensitiser with a laser-assisted process and evaluated adhesive-dentin bond strength. Methods: Thirty dentin discs were divided into two groups according to whether the selected desensitiser (TeethMate; Kuraray Noritake) was used prior to dentin bonding. Each group was subdivided into three subgroups (n = 5): A- Adhesive (Single Bond Universal, 3M ESPE), AL- Adhesive + Laser (Nd:YAG 60 mJ) and LAL- Laser + Adhesive + Laser. Dentin permeability values (%) were recorded before and after desensitiser application. Resin composites were placed over the bonded specimens; the latter were aged prior to microtensile bond strength evaluation. Gelatinolytic activity within the hybrid layers was examined with in-situ zymography using confocal laser scanning microscopy. Data were analysed with ANOVA and Tukey test (α = 0.05). ResultsSignificant differences in dentin permeability were identified for all groups (p = 0.00). Both laser treatment (p = 0.182) and desensitiser application (p = 0.687) did not significantly improve dentin bond strength. Ultrastructure of the resin-dentin interface identified presence of calcium phosphate within dentinal tubules. Laser treatment did not affect hybrid layer ultrastructure. Both treatment modalities (intratubular CaP occlusion and laser) had no influence on gelatinolytic activity within hybrid layers. ConclusionAlthough intratubular CaP occlusion and laser treatment were effective in reducing dentin permeability, they did not affect bond strength, interfacial ultrastructure and gelatinolytic activity within hybrid layers. Clinical relevanceTreatment of etched dentin with Nd:YAG Laser at 60 mJ does not adversely affect collagen ultrastructure and gelatinolytic activity within the hybrid layer. The application of a calcium phosphate-based desensitiser to etch dentin does not affect dentin bond strength.

Microtensile Bond Strength Evaluation of Composite Resin to Discolored Dentin After Amalgam Removal

BackgroundTo obtain prolonged clinical success with composite restorations, better bonding of resin to the tooth substrate is crucial.AimThe study was aimed to evaluate the microtensile bond strength (µTBS) of bulk-fill composite resin restorations when bonded to a cavity previously restored with amalgam, comparing with that of freshly prepared dentin.Materials and methodMesio-occlusal cavity preparations were done on 80 extracted human mandibular molars with a buccolingual width of 4 mm and a 1.5 mm axial depth by placing the gingival seat 0.5 mm coronal to the cementoenamel junction (CEJ) and were restored with fine-grain amalgam alloy. After thermocycling, the amalgam restorations were removed. Disto-occlusal cavities with similar dimensions of mesial cavities were prepared, and both the proximal surfaces were filled with bulk-fill composite using either etch-and-rinse or self-etch adhesives. Following thermomechanical cyclic loading, all the teeth were sectioned for µTBS testing. Bond strength data expressed in megapascals (MPa) were subjected to statistical analyses using analysis of variance (ANOVA) and Tukey’s multiple post-hoc tests.ResultsThe total-etch adhesive exhibited statistically higher bond strength values to both dentin substrates compared to self-etch adhesives (p<0.05). Failure mode analysis reported more of adhesive failures.ConclusionThe µTBS of bulk-fill composite resin restorations bonded to a cavity previously restored with amalgam was significantly lower than that of freshly prepared dentin. Total-etch adhesives bond strength was higher than self-etch adhesives to both the substrates tested.

Evaluation of Micro-Tensile Bond Strength of Two Types of Resin Ceramics with Dentin After Different Surface Treatments

Evaluation of Micro-Tensile Bond Strength of Two Types of Resin Ceramics with Dentin After Different Surface Treatments

Evaluation of Micro-Tensile Bond Strength of Two Types of Resin ceramics with dentin after different surface treatments.

Abstract: Objective: The objective of this study was intended for evaluation the effect of different surface treatments on microtensile bond strength of two different luting resin cements to two CAD/CAM resin ceramic materials with dentin. Materials and Methods: A total number of 112 samples were used for microtensile bond strength test (µ-TBS). Samples were divided into two equal main groups according to type of resin ceramic used (Vita Enamic [ENA] and Lava Ultimate [LVU]). Then each main group was subdivided according to the surface treatment performed into four equal subgroups; Gr 1 (sandblasting (SB) with Al2O3 50µm), Gr 2(sandblasting (SB) with Al2O3 110µm), Gr 3 (plasma etching), and Gr 4 (Hydrofluoric acid (HF) plus Silane), then two types of resin cements (Rely X Ultimate, Panavia f 2.0) were applied to the treated ceramics in each group. µ-TBS test was performed and the data statistically analyzed. Results: The results of this study revealed that; LVU recorded statistically significant higher µ-TBS than ENA. Rely X Ultimate recorded statistically significant higher µ-TBS than Panavia F 2.0. Conclusion: LVU has higher µ-TBS than ENA with all surface treatments except with HF plus Silane ENA has higher µ-TBS than LVU. Key Words: Resin ceramic, Resin cement, sandblasting, Plasma, Hydrofluoric acid.