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Non-additive mixing plays a key role in the properties of molecular fluids and solids. In this work, the potential for athermal order–disorder phase transitions is explored in non-additive binary colloidal nanoparticles that form substitutionally ordered compounds, namely, for equimolar mixtures of octahedra + spheres, which form a CsCl lattice compound, and cubes + spheres, which form a NaCl crystal. Monte Carlo simulations that target phase coexistence conditions were used to examine the effect on compound formation of varying degrees of negative non-additivity created by component size asymmetry and by size-tunable indentations in the polyhedra's facets, intended to allow the nestling of neighboring spheres. Our results indicate that the stabilization of the compound crystal requires a relatively large degree of negative non-additivity, which depends on particle geometry and the packing of the relevant phases. It is found that negative non-additivity can be achieved in mixtures of large spheres and small cubes having no indentations and lead to the athermal crystallization of the NaCl lattice. For similarly sized components, athermal congruent transitions are attainable and non-additivity can be generated through indentations, especially for the cubes + spheres system. Increasing indentation leads to lower phase coexistence free energy and pressure in the cubes + spheres system but has the opposite effect in the octahedra + spheres system. These results indicate a stronger stabilizing effect on the athermal compound phase by the cubes' indentations, where a deeper nestling of the spheres leads to a denser compound phase and a larger reduction in the associated pressure-volume free-energy term. [ABSTRACT FROM AUTHOR]

Purpose: To inves)gate the effect of irradia)on)me and zirconia thickness using low power Er,Cr:YSGG laser irradia)on (for debonding purposes) on the thermal changes and shear bond strength (SBS) of resin-bonded 3% mol yIrium oxide stabilized tetragonal zirconia polycrystal (3YTZP) specimens. Materials and Methods: 3Y-TZP slices of 0.5-, 2-, and 3-mm thick were used. The temperatures during laser irradia)on using single spot irradia)on at different)mes (30 seconds, 60 seconds, 90 seconds, and 120 seconds) and line scanning irradia)on from one spot to another at three different distances (2, 4, and 6 mm) were recorded. Single spot and line scanning irradia)on data were analyzed using three-way ANOVA (a = .05) and generalized linear mixed model, respec)vely. Nonirradiated (control) and irradiated resin-bonded 3Y-TZP specimens were shear tested, and the data were analyzed using two-way ANOVA (a = .05). Results: Under single spot irradia)on, the laser-induced temperature was higher through thin 3Y-TZP at any)me compared to thick 3Y-TZP. For the line scanning method, short distances (2 and 4 mm) resulted in a significant increase in temperature for 0.5-mm thick specimens. Laser irradia)on significantly decreased the SBS of the 0.5-mm group compared to the nonirradiated group. A_er irradia)on, the bond strength of the 2- and 3-mm thick 3Y-TZP was similar to the nonirradiated group. Conclusions: The temperature and bond strength of low-power laser irradiated 3Y-TZP specimens was affected by the specimen thickness but not by the irradia)on)me tested. Low-power laser irradia)on is an effec)ve debonding method for thin Y-TZP restora)ons. [ABSTRACT FROM AUTHOR]

The structure of grain boundaries (GBs) of metals is essential in determining the solute segregation at GBs; however, its complexity prohibits the understanding of the underlying mechanism. We propose a geometric descriptor of GB segregation based on the non-local coordination number of cut surfaces from GBs, which determines the segregation energies of solutes at the grain boundaries of metals across multidimensional GB space, different solutes, and different matrices. The effectiveness of the descriptor originates from the correlation between bonding strength, d-band width, and coordination number. This descriptor only depends on the bond length and angle of pre-segregation sites at GBs and can be readily used for description and prediction. Our scheme builds a novel picture for understanding the role of GB structures in segregation and provides a useful tool for the design of advanced alloys. [ABSTRACT FROM AUTHOR]

The photochemical dynamics of the acetic acid and trifluoro-acetic acid dimers in hexane are studied using time-resolved infrared absorption spectroscopy and ab initio electronic structure calculations. The different hydrogen bond strengths of the two systems lead to changes in the character of the accessed excited states and in the timescales of the initial structural rearrangement that define the early time dynamics following UV excitation. The much stronger hydrogen bonding in the acetic acid dimer stabilizes the system against dissociation. Ground state recovery is mediated by a structural buckling around the hydrogen bond itself with no evidence for excited state proton transfer processes that are usually considered to drive ultrafast relaxation processes in hydrogen bonded systems. The buckling of the ring leads to relaxation through two conical intersections and the eventual reformation of the electronic and vibrational ground states on a few picosecond timescale. In trifluoro-acetic acid, the weaker hydrogen bonding interaction means that the dimer dissociates under similar irradiation conditions. The surrounding solvent cage restricts the full separation of the monomer components, meaning that the dimer is reformed and returns to the ground state structure via a similar buckled structure but over a much longer, ∼100 ps, timescale. [ABSTRACT FROM AUTHOR]

Noncovalent bonding between atmospheric molecules is central to the formation of aerosol particles and cloud condensation nuclei and, consequently, radiative forcing. While our understanding of O–H⋯B interactions is well developed, S–H⋯B hydrogen bonding has received far less attention. Sulfur- and nitrogen-containing molecules, particularly amines, play a significant role in atmospheric chemistry, yet S–H⋯N interactions are not well understood at a fundamental level. To help characterize these systems, H2S and methyl-, ethyl-, n-propyl-, dimethyl-, and trimethylamine (MA, EA, n-PA, DMA, and TMA) have been investigated using matrix isolation Fourier transform infrared spectroscopy and high-level theoretical methods. Experiments showed that H2S forms hydrogen bonded complexes with each of the amines, with bond strengths following the trend MA ≈ EA ≈ n-PA < TMA ≤ DMA, in line with past experimental work on H2SO4·amine complexes. However, the calculated results indicated that the trend should be MA < DMA < TMA, in line with past theoretical work on H2SO4·amine complexes. Evidence of strong Fermi resonances indicated that anharmonicity may play a critical role in the stabilization of each complex. The theoretical results were able to replicate experiment only after binding energies were recalculated to include the anharmonic effects. In the case of H2SO4·amine complexes, our results suggest that the discrepancy between theory and experiment could be reconciled, given an appropriate treatment of anharmonicity. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of adding tea tree oil to denture liners on Candida albicans and bond strength to the acrylic denture base. Materials and Methods: Disc-shaped specimens were fabricated from silicone-based resilient liner (Tokuyama, Molloplast), acrylic-based hard liner (GC Reline), and acrylic-based soft liner (Visco-gel). Tea tree oil (TTO) was incorporated into the liners at varying concentrations (0% [control], 2%, 5%, 8%). C albicans were counted by viable colony count, and optical density (OD) was measured with a spectrophotometer. The tensile strength to heat polymerized acrylic denture base was measured in a universal testing machine. The compliance of the data to the distribution of normality was evaluated using the Shapiro Wilk test. Two-way ANOVA, Bonferroni correction, and paired sample t test were performed (α = .05). Results: The addition of TTO into liners provided a significant decrease in the OD values (P < .001). The control groups of the liners presented the highest colony counts, whereas increasing TTO decreased the results (P < .01). According to tensile bond strength test, 8% TTO addition resulted in a significant decrease for Tokuyama (P < .01) and Molloplast liners (P < .05), while 2% TTO resulted in significance for GC Reline (P < .001). Conclusions: Denture liners containing increasing percentages of TTO presented lower amounts of C albicans colonies and decreased bond strength to the denture bases. When using TTO for its antifungal properties, the amount added should be carefully selected because the tensile bond strength may be affected. [ABSTRACT FROM AUTHOR]

Purpose: To systematically review in-vitro studies that evaluated the influence of erbium laser pretreatment on dentin shear bond strength (SBS) and bond failure modes. Materials and Methods: Electronic databases (PubMed, Cochrane Central, Embase, and Web of Science) were searched. Only in-vitro studies involving erbium laser irradiation of the dentin surface and SBS testing of the bonded resin block were included. The three common modes of bond failure (1. adhesive, 2. cohesive, and 3. mixed) were observed and analyzed. The network meta-analysis (NMA) was performed by Stata 15.0 software, the risk of bias was evaluated, and the certainty of the evidence was assessed by the Confidence in Network Meta-analysis (CINeMA). Results: Forty studies with nine pretreatments (1. blank group: BL; 2. phosphoric acid etch-and-rinse: ER; 3. self-etch adhesive: SE; 4. Er:YAG laser: EL; 5. Er,Cr:YSGG laser: ECL; 6. ER+EL; 7. ER+ECL; 8. SE+EL; 9. SE+ECL) were included in this analysis. The NMA of SBS showed that ER+EL [SMD = 0.32, 95% CI (0.11, 0.98)] had the highest SBS next to ER, especially when using one of the 3M ESPE adhesives, followed by EL, ECL, SE and SE+EL. The Ivoclar Vivadent adhesives significantly increased the SBS of the ECL [SMD = 0.37, 95% CI (0.16,0.90)] and was higher than ER+EL [SMD = 0.25,95% CI (0.07,0.85)]. Finally, the surface under the cumulative ranking curve (SUCRA) value indicated that ER+EL (SUCRA = 71.0%) and EL (SUCRA = 62.9%) were the best treatments for enhancing dentin SBS besides ER. ER+EL (SUCRA = 85.3%), ER (SUCRA = 83.7%) and ER (SUCRA = 84.3%) had the highest probability of occurring in adhesive, cohesive and mixed failure modes, respectively. Conclusion: Er:YAG and Er,Cr:YSGG lasers improved dentin SBS compared to the blank group, especially when the acid etch-and-rinse pretreatment was combined with Er:YAG laser. Shear bond strength and failure mode do not appear to be directly related. [ABSTRACT FROM AUTHOR]

Purpose: To measure zirconia-to-zirconia microtensile bond strength (µTBS) using composite cements with and without primer. Materials and Methods: Two Initial Zirconia UHT (GC) sticks (1.8x1.8x5.0 mm) were bonded using four cements with and without their respective manufacturer's primer/adhesive (G-CEM ONE [GOne] and G-Multi Primer, GC; Panavia V5 [Pv5]), and Panavia SA Cement Universal [PSAu], and Clearfil Ceramic Plus, Kuraray Noritake; RelyX Universal (RXu) and Scotchbond Universal Plus [SBUp], 3M Oral Care). Specimens were trimmed to an hour-glass shaped specimen whose isthmus is circular in cross-section. After 1-week water storage, the specimens were either tested immediately (1-week µTBS) or first subjected to 50,000 thermocycles (50kTC-aged µTBS). The fracture mode was categorized as either adhesive interfacial failure, cohesive failure in composite cement, or mixed failure, followed by SEM fracture analysis of selected specimens. Data were analyzed using linear mixed-effects statistics (α = 0.05; variables: composite cement, primer/adhesive application, aging). Results: The statistical analysis revealed no significant differences with aging (p = 0.3662). No significant difference in µTBS with/without primer and aging was recorded for GOne and PSAu. A significantly higher µTBS was recorded for Pv5 and RXu when applied with their respective primer/adhesive. Comparing the four composite cements when they were applied in the manner that resulted in their best performance, a significant difference in 50kTC-aged µTBS was found for PSAu compared to Pv5 and RXu. A significant decrease in µTBS upon 50kTC aging was only recorded for RXu in combination with SBUp. Conclusion: Adequate bonding to zirconia requires the functional monomer 10-MDP either contained in the composite cement, in which case a separate 10-MDP primer is no longer needed, or in the separately applied primer/adhesive. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the long-term microtensile bond strength (µTBS) to dentin, water sorption (WSP) and solubility (WSL), and degree of conversion (DC) of self-adhesive resin composites (SACs). Materials and Methods: The mid-coronal dentin of human molars was exposed, and teeth were randomly assigned to five groups according to the SACs (n = 10): 1. FIT SA F03 (FIT); 2. Experimental (EXP); 3. Fusio Liquid Dentin (FLD); 4. Vertise Flow (VER); 5. Constic (CON). The µTBS was evaluated after 24 hours (24 h) and 6 months (6 m) storage. A scanning electron microscope examined failure modes and resin-dentin interfaces. The WSP and WSL (n = 5) were evaluated following ISO 4049:2019 specifications, and DC (n = 3) was measured using Raman spectroscopy. The statistical analyses were performed accepting a significance level of p = 0.05. Results: FIT, EXP, and FLD produced significantly higher µTBS median values than VER and CON after 24 h and 6 m (p < 0.05). After 6m, the µTBS median of FIT and EXP significantly decreased (p < 0.05), while FLD, VER, and CON showed no significant difference (p > 0.05). FLD and CON exhibited lower WSP than FIT, EXP, and VER (p < 0.05). FLD presented the lowest (p < 0.05), and VER revealed the highest WSL (p < 0.05). FIT and EXP showed the highest (p < 0.05), and VER demonstrated the lowest DC (p < 0.05). Conclusions: Following the present study's design, SACs' bonding performance and physical properties remained restricted. Therefore, the application should be considered cautiously, and further clinical trials are necessary to evaluate their long-term performance. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the influence of contamination and different cleaning methods on resin bonding to cobalt-chromium (CoCr) alloy disks. Materials and Methods: A total of 160 CoCr disks were divided into 3 groups. The first group (N = 64) was air abraded with alumina particles; the second group (N=64) was air abraded and contaminated with silicone disclosing agent and saliva; the third group (N=32) was neither air abraded nor contaminated. The first two groups were divided into 4 subgroups (N = 16) according to the cleaning method: ultrasonic bath in 99% isopropanol, use of a cleaning suspension of zirconium oxide particles, use of a cleaning suspension based on 10-MDP salt, and treatment with atmospheric plasma. The third group was divided into 2 subgroups (N = 16): treatment with atmospheric plasma and no treatment. All CoCr specimens were bonded to plexiglas tubes filled with a bonding resin that contained phosphate monomer. Tensile bond strength (TBS) was examined by tensile testing after 3 and 150days of water storage plus 37,500 thermal cycles (N = 8). Results: After contamination, TBS was significantly reduced after 150days of water storage. Groups without air abrasion showed initially low TBS and debonded spontaneously after 150days of water storage. Conclusion: None of the cleaning methods was able to remove saliva and silicone disclosing agent on CoCr-alloy surfaces. Surface activation by plasma treatment has no long-term effect on the bond strength. [ABSTRACT FROM AUTHOR]

Purpose: This investigation aimed to assess the impact of additive manufacturing-generated surface textures on zirconia bond strength. Materials and Methods: Zirconia samples (n = 144) fabricated using digital light-processing (DLP) technology were categorized into 6 groups according to the type of surface conditioning (group NN: no designs, no air abrasion; group NY: no designs, with air abrasion; group GN: groove designs, no air abrasion; group GY: groove designs with air abrasion; group HN: hexagon grid, no air abrasion; group HY: hexagon grid, with air abrasion). Composite resin cylinders were cemented to the treated zirconia surfaces with dual-curing, self-adhesive resin cement (Clearfil SA Luting). The shear bond strength (SBS) was tested after water storage for 3 days or 3 days with an additional 10,000 thermocycles. Results: The zirconia samples fabricated using DLP technology have high accuracy. The SBS of the NY, GY, and HY groups did not significantly differ after 3 days, and neither did the SBS of the NN, GN, and HN groups. The NN, NY, and HY groups exhibited reduced SBS compared to their initial values following artificial aging, while the SBS of the remaining three groups were not diminished. The GY group obtained the highest SBS value after aging. Conclusion: Printing grooves with air abrasion can improve the bond strength. [ABSTRACT FROM AUTHOR]

Purpose: Multiple materials are found in the root canal after fiber-post cementation. The layer of a bioceramic-based (BC) sealer may affect the bond strength (oBS) of the fiber post in the root canal. The purpose of this study was to employ multilayer composite-disk models in diametral compression to investigate whether the bond strength between a fiber post and root dentin can be increased by the application of a primer on the BC sealer. Materials and Methods: The multilayers of materials in the root canal required 3D finite-element (FE) stress analyses (FEA) to provide precise oBS values. First, BC sealer was characterized using x-ray powder diffraction (XRD) to determine when the sealer completely set and the types of crystals formed to select which primer to apply to the sealer. We selected a 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP)-based primer to treat the BC sealer before post cementation. Ultra-highspeed (UHS) imaging was utilized to analyze the crack initiation interface. The obtained failure force was used in FE analysis to calculate oBS. Results: UHS imaging validated the fracture interface at the post-dentin junction as FEA simulations predicted. oBS values of the fiber posts placed with various material combinations in the root canal were 21.1 ± 3.4 (only cement/post), 22.2 ± 3.4 (BC sealer/cement/post) and 28.6 ± 4.3 MPa (10-MDP primer treated BC sealer/cement/post). The 10-MDP-treated BC sealer exhibited the highest oBS (p < 0.05). Conclusion: The multilayer composite disk model proved reliable with diametral compression testing. The presence of BC sealer in the root canal does not reduce oBS of the fiber post. Conditioning the BC sealer layer with 10-MDP primer before fiber-post cementation increases oBS. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated and compared the bond strengths, microleakage, microgaps, and marginal adaptation of self-adhesive resin composites (SAC) to dentin with or without universal adhesives. Materials and Methods: Dentin surfaces of 75 molars were prepared for shear and microtensile bond strength testing (SBS and μTBS). Silicon molds were used to build up direct restorations using the following materials to form 5 groups: 1. Surefil One; 2. Prime&Bond active Universal Adhesive + Surefil One; 3. Vertise Flow; 4. OptiBond Universal + Vertise Flow; 5. Scotchbond Universal + Filtek Z500 (control group). Bonded specimens were thermocycled 10,000x before being tested either for SBS or μTBS using a universal testing machine at a crosshead speed of 0.5mm/min. Direct mesial and distal class-II cavities were created on 100 sound premolars, with the gingival margin of distal cavities placed below CEJ and restored according to the five groups. After thermocycling, microleakage scores were assessed following immersion of restored premolars in 2% methylene blue dye for 24h, while marginal gaps and adaptation percentages were investigated on epoxy resin replicas under SEM at magnifications of 2000X and 200X, respectively. Results were statistically analyzed with parametric and non-parametric tests as applicable, with a level of significance set at a = 0.05. Results: Bond strengths, microleakage scores, microgaps, and percent marginal adaptation of Surefil One and Vertise Flow were significantly (p<0.001) inferior to the control group. Dentin preconditioning with universal adhesives significantly increased the study parameter outcomes of Surefil One and Vertise Flow, yet they were still significantly below the performance of the control group. Conclusion: Conventional resin composite outperformed the SAC whether applied solely or in conjunction with their corresponding universal adhesives. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the bonding effectiveness of two HEMA/BPA-free universal adhesives (UAs) to flat dentin, to characterize their adhesive-dentin interfacial ultrastructure, and to measure their water sorption (Wsp), water solubility (Wsl), and hydrophobicity. Materials and Methods: The immediate and aged (50,000 thermocycles) microtensile bond strength (μTBS) to flat dentin of the HEMA/BPA-free UAs Healbond Max (HbMax; Elsodent) and Healbond MP (HbMP; Elsodent) as well as the reference adhesives OptiBond FL (Opti-FL; Kerr), Clearfil SE Bond 2 (C-SE2; Kuraray Noritake), and Scotchbond Universal (SBU; 3M Oral Care) was measured. The adhesive-dentin interfaces of HbMax and HbMP were characterized by TEM. Wsp and Wsl of all adhesive resins and of the primer/adhesive resin mixtures of HbMax, Opti-FL, and C-SE2 were measured. Hydrophobicity was determined by measuring the contact angle of water dropped on adhesive-treated dentin. Results: In terms of μTBS, HbMax and HbMP performed statistically similarly to Opti-FL and C-SE2, but outperformed SBU. Aging only significantly reduced the μTBS of SBU when applied in E&R bonding mode. TEM revealed typical E&R and SE hybrid-layer ultrastructures at dentin, while electron-lucent globules of unknown origin, differing in size and shape, were observed within the adhesive resin of HbMP and even more frequently in that of HbMax. Higher Wsp was measured for the primer/adhesive resin mixtures than for the adhesive resins. Opti-FL was more hydrophobic than all other adhesives tested. Conclusion: The HEMA/BPA-free UAs bonded durably to flat dentin with bond strengths comparable to those of the goldstandard E&R/SE adhesives and superior to that of the HEMA/BPA-containing 1-step UA. [ABSTRACT FROM AUTHOR]

Purpose: To compare the adhesion of a self-curing (Tokuyama Universal Bond, TUB) and a light-curing (Scotchbond Universal, SBU) universal adhesive to CAD/CAM materials, enamel, and dentin. This study also assessed differences in enamel adhesion between self-etch vs selective etching modes, as well as immediate and long-term adhesion to dentin for both adhesives. Materials and Methods: Shear bond strength (SBS) testing was used to assess adhesion to enamel, dentin, Lava Ultimate (LU), Vita Enamic (VE), IPS e.max CAD (LD), IPS e.max ZirCAD (3Y-Zir), and Lava Esthetic (5Y-Zir) (n = 10). Moreover, bonding to enamel in self-etch and selective etching modes (n = 10) as well as immediate and aged resin-dentin bond strength (24 h after bonding, after 100,000 thermal cycles [TC] and long-term storage) was evaluated using the microtensile bondstrength test (n = 30). Failure mode was also determined for the bonding to dentin. Statistical analyses consisted of oneway and two-way ANOVA with appropriate post-hoc Tukey-Kramer or two-sample t-tests, as well as the chi-squared or Fisher's exact test (a = 0.05). Results: TUB and SBU universal adhesives presented similar bonding to LU, VE, 3Y-Zir, and 5Y-Zir. However, SBS for TUB was superior to SBU when bonding to lithium-disilicate glass-ceramic (IPS e.max CAD). SBU showed better adhesion to dentin and enamel when used in the self-etch mode, while TUB promoted strong bond strength to enamel in the selective etching mode. TUB after TC was the only aging condition that yielded a significant reduction in resin-dentin bond strength. Conclusion: In-vitro adhesion performance of the self-curing and light-curing universal adhesives varies depending on the dental substrate or CAD/CAM restorative material used for bonding. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of different lithium-disilicate (LiSi) glass-ceramic surface decontamination procedures on the shear bond strength (SBS) to resin cement. Materials and Methods: Seventy CAD/CAM LiSi ceramic specimens (IPS e.max CAD, Ivoclar) were cut and sintered. Fifty specimens were treated with 5% hydrofluoric acid (HF) for 20 s, while 20 were left untreated. All 70 specimens were then contaminated with human saliva and try-in silicone paste. The following surface cleaning methods were investigated (n = 10): C: water rinsing (control); PA: 37% H3PO4 etching for 20 s; E: 70% ethanol applied for 20 s; CP: cleaning paste (Ivoclean, Ivoclar) brushed for 20 s; HFSEP: self-etching ceramic primer (Monobond Etch&Prime, Ivoclar) rubbed for 20 s; HF: 5% HF applied for 20 s or no HF etching prior to contamination; SEP: self-etching ceramic primer rubbed for 20 s and no HF etching prior to contamination. Composite cylinders were created and luted with an adhesive resin cement to the decontaminated surfaces. After storage for 24 h at 37°C, the SBS test was conducted. Two fractured specimens per group were observed under SEM to perform fractographic analysis. The data were statistically analyzed with p set at <0.05. Results: The type of surface cleaning approach influenced bond strength (p < 0.001). HFSEP, SEP, and HF attained higher SBS (p < 0.001) compared to other groups. None of the approaches were able to completely remove contaminants from the ceramic surfaces. SEM images showed residual traces of contaminants on CP-treated surfaces. Conclusions: The self-etching ceramic primer enhanced bond strength to contaminated LiSi ceramic surfaces, irrespective of previous treatment with hydrofluoric acid. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the microtensile bond strength (µTBS) to dentin in class-I cavities using different layering techniques, adhesive application modes, and aging. Materials and Methods: 150 caries-free human molars were randomly assigned to 8 experimental and 2 control groups (n=15 teeth/group). For each tooth, a standardized class-I cavity was prepared (4x4x4 mm) and pretreated with a universal adhesive (self-etch or etch-and-rinse mode). Incrementally layered restorations served as the control. In the experimental groups, either lining with bulk-fill flowable composite and a layering technique, bulk filling, or the snowplow technique with one or two layers of viscous composite were applied. Four microsticks were obtained from each cavity. Half were tested initially and the other half after aging (thermocycling, 15,000 cycles, 5-55°C, n=30 sticks/group). Tobit regression was used for analyzing group differences, including analysis of interactions, Pearson's chi-squared test or Fishers's exact test for fracture analyses (significance level 0.05). Results: Regression analysis showed significant differences in µTBS between groups initially and after aging. In both etching modes, lining with a bulk-fill flowable composite and layering technique achieved the highest µTBS both initially and after aging. In contrast to the etching mode (self-etch < etch-and-rinse), aging did not influence µTBS significantly. The predominant failure types were adhesive and mixed, with a significantly lower number of pre-test failures in the etch-and-rinse groups. Conclusion: The etch-and-rinse mode achieves higher µTBS in class-I cavities compared to the self-etch mode. The lining technique with bulk-fill flowable composite as well as the snowplow technique yielded the highest µTBS after aging, whereas bulk filling and its combination with the snowplow technique resulted in lower µTBS. [ABSTRACT FROM AUTHOR]

Purpose: To identify the most effective protocol for bonding denture bases and artificial teeth made with different computer-aided design and manufacturing (CAD/CAM) materials (milled and 3D-printed) and conventional heat-polymerized resins. Materials and Methods: This review was performed according to the Preferred Reporting Items for Systematic and Meta-Analysis (PRISMA) criteria and registered in the International Prospective Registry of Systematic Reviews PROSPERO (CRD42021276084). An electronic search was performed independently by two examiners in PubMed/MEDLINE, Cochrane Library, Scopus, Web of Science, ProQuest, and OpenGrey databases for articles published up to and including December 2021. Results: The electronic search returned 806 articles, and after duplicates were removed, 589 articles remained. Four articles met the eligibility criteria to be included in this study. After evaluating the different combinations of denture base materials and artificial teeth, it was found that IvoBase CAD Bond (Ivoclar Vivadent) was effective for bonding CAD/CAM denture bases to prefabricated acrylic resin teeth, which showed no differences compared to the heat-polymerized resin denture base bonded to prefabricated acrylic resin teeth (2: 68.56; I2: 96%; P < .001). Conclusions: The IvoBase CAD Bond bonding system can be used for the fabrication of CAD/CAM denture bases with prefabricated acrylic resin teeth. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of three different curing protocols based on different ratios of self-curing and light-curing periods on the bond strength and nanoleakage of fiber posts luted with dual-curing selfadhesive cements. Materials and Methods: A total of 48 single-root teeth were endodontically treated and obturated, and an 8-mm post space was prepared with dedicated drills. Specimens were randomly divided into two groups according to the self-adhesive cement employed: group 1 (G1) = PANAVIA SA Plus (Kuraray Noritake), and group 2 (G2) = Bifix SE (VOCO). The specimens were further divided into three subgroups (n = 8 each) according to the light-curing protocol applied: no light-curing (SG1), 20 seconds of light-curing 20 seconds after cement injection (SG2), and 20 seconds of light-curing 120 seconds after cement injection (SG3). Slices of 1-mm thickness were prepared for the pushout test and nanoleakage analyses of the coronal and apical regions after 24 hours of storage in artificial saliva. Results were statistically analyzed with threeway ANOVA and Tukey post hoc tests. Statistical significance was set for P < .05. Results: Three-way ANOVA analysis showed that the factors of cement (P = .02) and curing protocol (P < .001) had a significant influence on bond strength. Tukey post hoc test reported that light-curing 120 seconds after injection showed higher bond strength compared to both no light-curing and photoactivation after 20 seconds. Conclusion: To achieve the highest bond strength with self-adhesive cements, photoactivation with a 120-second delay after mixing is required. There is no difference between light-curing immediately and light-curing 20 seconds after mixing. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate different protocols for recementation of dislodged glass fiber posts (GFPs).Materials and Methods: The root canals of 50 bovine incisors were prepared to receive GFPs, which were conditioned with 24% hydrogen peroxide, silanized, and cemented with a self-adhesive resin cement. After light curing, the specimens were submitted to a pullout test. The dislodged GPFs were distributed into five experimental groups (n = 10 each) according to surface treatment for recementation: NT = no treatment; SI = silane; ET = 92.8% ethanol/silane; HP = 24% hydrogen peroxide/silane; AL = airborne-particle abrasion (50-μm alumina)/silane. The GFPs were recemented with the same self-adhesive resin cement, and specimens were submitted to a second pullout test. Data were analyzed by Student t test and one-way ANOVA (α = .05).Results: For all groups, the recementation bond strength was higher than the strength obtained after the first cementation (P < .05). There were no statistical differences among the experimental recementation protocols (P = .096).Conclusion: All recementation protocols might be reliably applied since they led to higher bond strength than the first cementation. [ABSTRACT FROM AUTHOR]

Laser stripping technology is an advanced processing method with high efficiency and low material loss, which can greatly reduce material loss in the production process of single-crystal SiC wafer, but the single-crystal SiC ingot still have a certain bonding force after laser modification. Ultrasonic vibration can reduce the bonding force and thus strip single-crystal SiC wafer. In order to investigate the effect of ultrasonic vibration on the reduction of the bonding force of single-crystal SiC internal modification layer, through the ultrasonic-assisted stripping of single-crystal SiC orthogonal experiment, the ultrasonic vibration parameters of ultrasonic frequency, vibration time and ultrasonic power of the three indexes of the reduction of the bonding force was analyzed. The results show that the bonding force of the modified layer decreased by 25 %–60 % after ultrasonic vibration. Variance analysis of the experiment results showed that the main factors influencing the bond strength reduction were vibration time and ultrasonic power in turn. When the vibration time is longer and the ultrasonic power is higher, the stripping force decreases more, and the stripping force of single-crystal SiC wafers decreases up to 60 % under the condition of vibration time of 5min and ultrasonic power of 700 W. Through analysis of the single-crystal SiC cross-section, distinct cleavage steps and cleavage channels are evident. The laser-modified region exhibits defect such as nano-pores, micro-cracks, and nano-particles. After the single-crystal SiC laser modification process was upgraded, the distance between the ultrasonic tool head and the single-crystal SiC was 1.5 mm can directly strip off the single-crystal SiC wafer. And eventually stripped 6-inch single-crystal sic wafers. Therefore, ultrasonic vibration can increase the internal defects in the single-crystal SiC modified layer, causing crack expansion to occur and ultimately stripping the single-crystal SiC wafer. [ABSTRACT FROM AUTHOR]

This study examines the impact of the bonding temperature parameter on the quality of diffusion brazing joints of B 4 C ceramics using a Ni-Cr-Si-Fe-B interlayer. Various factors including shear strength, hardness, microstructure, interfacial phenomena, elemental diffusion patterns, formed compounds and phases, and fracture surfaces of the samples were analyzed and compared. The brazed sample at 1110 °C for 1/2 h exhibited the highest shear strength of 62 MPa. Increase of the bonding temperature to the optimum level (1090–1110 °C) enhances the fluidity of the molten interlayer, facilitating its diffusion into the porosities of the ceramic components. This increase also promotes higher interactions within the system, creating favorable conditions for element diffusion. However, surpassing the optimum temperature (1110–1130 °C) may lead to increased destructive reactions and intensify the impact of the coefficient of thermal expansion (CTE) mismatch, resulting in residual stresses and a subsequent decrease in bond strength. The excessive increase in the bonding temperature (1130–1150 °C) can lead to the excessive fluidity of the molten interlayer, potentially causing effusion onto the joint's fixture and damaging the samples. The results indicate the formation of various compounds between the elements of the interlayer and carbon and boron elements, including SiC, Ni 4 B 3 , CrB 2 , Fe 2 B, Ni 6 Si 2 B, and B 2 Fe 3 Ni 3 , at the fracture surface of the sample bonded at 1110 °C. The more substantial peaks of these compounds, compared to other samples, could be a reason for the higher strength of this particular sample. [ABSTRACT FROM AUTHOR]

Fully grouted rock bolts are widely used in mining, tunneling, and pit support, and thus the study of their anchorage performance is beneficial for optimizing the anchorage system design. In this study, an FDM‐DEM coupled numerical model is established to simulate the whole process of rock bolt pullout test and to investigate the failure mechanism of fully grouted rock bolts. The accuracy of the model is verified by comparison with existing laboratory test results. Virtual experiments are conducted on different models by eliminating the anchor plate, changing the layered rock strata condition, and adding bolts. The results show that the presence of an anchor plate will reduce tensile stress to restrain the rupture of surrounding rock and thus improve the strengthening effect. Due to the different bond strength and tensile strength of the soft and hard rock mediums, the layer sequence of the rock strata affects the maximum pullout force. The upper‐soft and lower‐hard composite rock strata (S‐HCR) exhibits single‐cone damage while the upper‐hard and lower‐soft composite rock strata (H‐SCR) exhibits double‐cone damage. The superposition effect of the anchor group on the stresses and displacements is the reason leading to the reduction of the maximum load‐bearing capacity of the rock bolts. [ABSTRACT FROM AUTHOR]

Alkali‐activated cement (AAC) is an alternative binder with a promising potential to replace ordinary Portland cement (OPC) and mitigate its environmental issues. The use of fiber‐reinforced polymer (FRP) reinforcements with AAC concrete enables the development of corrosion‐resistant, environmentally friendly reinforced concrete structures. Bond behavior is critical in reinforced concrete structures and must be thoroughly studied for such new alternative materials. This study employs pullout tests to investigate the bond behavior between FRP bars and fine‐grained AAC concrete. Three fine‐grained AAC concretes with low to high strength, glass and carbon FRP bars and wrapped, milled, and smooth surface treatments were examined. The effect of bar casting position was also investigated. The compressive strength showed a significant influence on the bond strength. An average bond strength of approximately 18 MPa was observed for both glass and carbon FRP bars when used with 65 MPa concrete. Both the glass and carbon FRP bars with wrapping showed a lower bond strength than their milled FRP bars counterparts. The carbon bars without surface preparation (smooth bars) resulted in a much lower bond strength, around 4 MPa. In terms of casting positions, the bars cast in the middle section of the concrete block showed a higher bond strength than those at the bottom and top. [ABSTRACT FROM AUTHOR]

The surface of carbon fiber is treated with sizing agent containing hydroxylated carbon nanotubes, fullerenols, and graphene oxide, respectively. The effects of carbon nanomaterials and their structures on the surface properties of carbon fiber, the interfacial properties and the mechanical properties of carbon fiber/epoxy composites are investigated. All three types of carbon nanomaterial can improve the interfacial bonding strength and modulus, thereby enhancing the interlaminar shear strength (ILSS) of composites. Moreover, the ILSS increases with the increase of interfacial bonding strength, due to the roughness and the number of active groups. Compared with the composite without carbon nanomaterials, the interfacial bonding strength of the three nanoparticle‐modified composites increased by 14%, 5% and 4%, the modulus increased by 10%, 26%, and 9%, and the ILSS increased by 14%, 8%, and 7%, respectively. The interfacial bonding strength has a more significant impact on the ILSS than the interfacial modulus. Highlights: CNTs, graphene oxide and fullerenols regulate the surface characteristics of carbon fibers.The influence of carbon nanomaterials on the interfacial properties of composites.The relationship between the fiber surface, the interface and the composites. [ABSTRACT FROM AUTHOR]

Quantitative molecular structure‐reactivity models are useful for generating predictions to guide synthesis design, and in formulating and testing mechanistic hypotheses. We report an expanded multivariate linear regression (MLR) model for the rate of (hetero)aryl (pseudo)halide oxidative addition to L2Pd(0), here exemplified by Pd(PCy3)2. This builds on a prior model from our group, with additional substrate classes (aryl chlorides and iodides) and reaction solvents (THF, toluene, THF/DMF mixture). Overall solvent effects across the entire substrate set are minimal under these conditions, enabling a unified MLR model without introduction of new molecular descriptors beyond the original five. Examining the mechanistic origin of the two molecular electrostatic potential (ESP) descriptors led to generation of a simpler, four descriptor model that is suitable for aryl halides, but not for 2‐halopyridines. Using this model we identified a mechanistic outlier, 2‐pyridyl triflate, which undergoes a nucleophilic displacement oxidative addition that does not involve the adjacent nitrogen atom. Finally, we discuss the relationship between C−X bond strength and oxidative addition rates, and compare the intrinsic bond strength index (IBSI) to bond dissociation enthalpy (BDE) as a bond strength descriptor. [ABSTRACT FROM AUTHOR]

Solid-state bonding can form when metallic microparticles impact metallic substrates at supersonic velocities. While the conditions necessary for impact-induced metallic bonding are relatively well understood, the properties emerging at the bonded interfaces remain elusive. Here, we use in situ microparticle impact experiments followed by site-specific micromechanical measurements to study the interfacial strength across bonded interfaces. We reveal a gradient of bond strength starting with a weak bonding near the impact center, followed by a rapid twofold rise to a peak strength significantly higher than the yield strength of the bulk material, and eventually, a plateau covering a large portion of the interface towards the periphery. We show that the form of the native oxide at the bonded interface—whether layers, particles, or debris—dictates the level of bond strength. We formulate a predictive framework for impact-induced bond strength based on the evolution of the contact pressure and surface exposure. In situ measurements reveal a significant strength gradient at interfaces formed by the supersonic impact of metallic microparticles on metallic surfaces, featuring weak central bonding and a rapid rise to a peak exceeding bulk material strength. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the bond strength between PEEK/PEKK and composite resins after various laser treatments and to compare the effectiveness of lasers on these polymers. 130 disc-shaped PEEK and PEKK blocks were obtained (10 mm diameter-4 mm height). One sample from each group (10 in total) was selected for scanning electron microscopy (SEM) analysis. The samples were randomly divided into 5 different surface treatment groups for each material (PEEK and PEKK): Er: YAG laser, Nd: YAG laser, diode laser, femtosecond laser and control (no surface treatment) (n = 12). Baseline and post-treatment surface roughness measurements were performed using a profilometer. The composite resin was bonded and SBS was measured. Comparisons among the groups were conducted via Kruskal–Wallis, one-way ANOVA; Tukey and Dunn tests were used as a post hoc test (p ≤ 0.05). All lasers significantly increased the roughness values of the PEEK and PEKK samples. In terms of shear bond strength; the Er: YAG and femtosecond laser groups had the highest values and the Nd: YAG, diode and control groups had the lowest values of the PEEK samples (p ≤ 0.05). The control group had the highest bond strength values and the femtosecond group had the lowest values for PEKK samples (p ≤ 0.05). All laser treatments increased the surface roughness of the PEEK and PEKK. Lasers increased the bond strength of PEEK to the veneering composite resin and decreased the bond strength values of PEKK. This shows that lasers behave differently in PEEK and PEKK materials. [ABSTRACT FROM AUTHOR]

Objective: This study aims to provide the impact of different endodontic irrigation treatments after post space preparation on the push‐out bond strength of fiber posts to dentin using self‐adhesive cements. Methods and Materials: A total of 180 extracted premolar teeth were selected. The canals were instrumented by and then were filled. After preparing the post space, teeth were divided into 12 groups according to irrigants (normal saline solution; 17% EDTA [ethylenediaminetetraacetic acid] + 5.25% NaOCl [sodium hypochlorite]; 17% EDTA; 5.25% NaOCl; and 1.2% chlorhexidine [CHX]) and irrigation technique (conventional syringe irrigation [CSI] and passive ultrasonic irrigation [PUI]). After cementation, the samples were sectioned to obtain 1‐mm disks from coronal and apical parts, a push‐out test was performed using a universal testing machine (Z050, Zwick/Roell, Ulm, Germany) at a speed of 1 mm/min. The data were analyzed using one‐way analysis of variance (ANOVA) and Mann–Whitney U tests. Results: The push‐out bond strength was higher in coronal segment in comparison to apical segment. The highest push‐out bond strength value was related to NaOCl + EDTA using PUI (12.39 ± 1.08). There are significant differences when comparing NaOCl + EDTA group with EDTA group using CSI or PUI technique (p < 0.05) except in coronal region with CSI technique. In both apical and coronal regions, phosphoric acid irrigation was found to be similar to normal saline solution and CHX groups regardless of activation technique. Conclusion: The push‐out bond strength values were significantly affected by the irrigation protocol. Using PUI and 17% EDTA + 5.25% NaOCl in apical region could be an effective irrigant for smear layer removal after post space preparation. [ABSTRACT FROM AUTHOR]

Introduction: Achieving strong bond strength of adhesive systems to deep dentin is challenging. Various methods to improve bond strength to deep dentin have been investigated. Chlorhexidine (CHX) enhances the longevity of the bond between adhesives and dentin by inhibiting the collagenolytic activity of Matrix Metalloproteinases (MMPs). Benincasa hispida is a natural plant-based functional food containing minerals and vitamins that help prevent osteoporosis and improve bone health. Aim: To evaluate the Microshear Bond Strength (MSBS) of a 10-methacryloyloxydecyl-dihydrogen Phosphate-based (10-MDP) universal adhesive system to coronal dentin with different dentin surface pretreatments, specifically CHX and Benincasa hispida. Materials and Methods: An in-vitro pilot study was conducted at the Department of Conservative Dentistry and Endodontics, Vishnu Dental College, Bhimavaram, Andhra Pradesh, India, from May 2023 to November 2023. Dentin discs (42) were prepared from human mandibular first molars. A standard etch-and-rinse protocol was performed on the discs. The specimens were assigned to different dentin pretreatments: Group-I (no pretreatment), Group-II (CHX) and Group-III (Benincasa hispida). CHX and Benincasa hispida were applied using micro applicator tips. A dentin bonding agent containing 10-MDP (DBA) was applied, photopolymerised and a composite restoration was fabricated. The MSBS to dentin was evaluated using a universal testing machine. The failure patterns were analysed using a stereomicroscope at 10x magnification. One-way Analysis of Variance (ANOVA) and Tukey's Honestly Significant Difference (HSD) HSD tests were used for statistical analysis, with a significance level set at α=0.05. Results: The mean MSBS values were 24.2732±5.41329 MPa for Group-III, 14.3848±4.23492 MPa for Group-II and 6.9724±3.15837 MPa for Group-I. Pretreatment of dentin with B. hispida resulted in significantly higher MSBS values compared to the other two groups (p<0.001*). Conclusion: Pretreatment with B. hispida significantly improved MSBS. Thus, B. hispida pretreatment may be beneficial in increasing dentin bond strength. [ABSTRACT FROM AUTHOR]

Active materials play a crucial role in the performance of phototransistors. However, the discovery of a novel and versatile active material is a big challenge. For the first time, phototransistors with ultrathin niobium‐doped indium oxide (InNbO) active layer are fabricated. The InNbO phototransistors without additional light‐absorbing layers exhibit the performance with a high average mobility of 22.86 cm2 V−1s−1, a turn‐on voltage of −0.75 V, a low sub threshold swing of 0.18 V/decade, and a high on/off current ratio of 5.74 × 108. Detailed studies show that Nb is the key to suppress the free carrier generation due to the strong bonding strength of Nb─O. In addition, the InNbO phototransistors exhibit a very broad spectral responsivity with a photocurrent of 4.72 × 10−4 A, a photosensitivity of 1.69 × 108, and a high detectivity of 3.33 × 1013 Jones under violet (405 nm) light illumination, which is significantly higher than that of the IGZO phototransistors. Furthermore, an active‐matrix quantum‐dot light‐emitting diode pixel circuit based on InNbO phototransistors is demonstrated. The findings not only indicate that InNbO is a new active material for phototransistors, but also suggest that InNbO‐based phototransistors have a great potential for the next‐generation interactive display technology. [ABSTRACT FROM AUTHOR]

This study investigates the shear bond strength between four widely used façade stones—travertine, granite, marble, and crystalline marble—and concrete substrates, with a particular focus on the role of polypropylene fibers in adhesive mortars. The research evaluates the effects of curing duration, fiber dosage, and mechanical anchorage on bond strength. Results demonstrate that Z-type anchorage provided the highest bond strength, followed by butterfly-type and wire tie systems. Extended curing had a significant impact on bond strength for specimens without anchorage, particularly for travertine. The incorporation of polypropylene fibers at 0.2% volume in adhesive mortar yielded the strongest bond, although lower and higher dosages also positively impacted the bonding. Furthermore, the study introduces a novel fuzzy logic model using the Dombi family of t-norms, which outperformed linear regression in predicting bond strength, achieving an R2 of up to 0.9584. This research emphasizes the importance of optimizing fiber dosage in adhesive mortars. It proposes an advanced predictive model that could enhance the design and safety of stone-clad façades, offering valuable insights for future applications in construction materials. [ABSTRACT FROM AUTHOR]

In order to find a suitable size of sheath duct and a reliable construction method for precast walls, a cast-in-place and five 1/2 scale precast drift-hardening concrete walls reinforced with weakly bonded ultra-high strength SBPDN rebars were fabricated and tested under reserved lateral load and constant compression. The experimental variables were the diameter of sheath ducts (45 mm, 100 mm, and 120 mm), embedded length (20d and 35d; d is the nominal diameter of SBPDN rebars), axial load ratio (0.075 and 0.15), and the construction method. The experimental observations, hysteresis behaviors, envelope curves, residual deformation, crack propagation, and energy dissipation were compared in the study. Moreover, a formula was applied to calculate the bond strength of the sheath duct. The experimental and calculated results revealed that increasing the axial load ratio and embedment length could not enhance the bond strength of the sheath ducts, and increasing the diameter decreased the bond strength significantly. Anchored the SBPDN rebars in smaller sheath ducts separately was a more stable connection method for precast concrete shear walls and provided sufficient drift-hardening capability, even at a large drift level (over 3%). [ABSTRACT FROM AUTHOR]

The bonding strength and LBE corrosion resistance of the Fe15Cr11Al2Si, Fe15Cr11Al0.5Y, and Fe15Cr11Al2Si0.5Y coatings heat‐treated at 500–650°C for 500 h were investigated. The results showed that the as‐deposited Fe15Cr11Al0.5Y coating has the strongest bonding strength with the F/M steel cladding tube compared with the Fe15Cr11Al2Si and Fe15Cr11Al2Si0.5Y coatings. Heat treatment deteriorates the bonding performance of the coatings, and obvious enrichment of Cr and Al elements appeared. The consumed Al element inside the heat‐treated coatings promotes the formation of Fe3O4 on the surface of the coatings after the corrosion test. The Y element can inhibit the enrichment of elements and the formation of Fe3O4. The bonding strength of the heat‐treated coatings can be improved after the corrosion test. The underlying mechanism of the evolution of microstructure and properties of the coatings after heat treatment and corrosion test was discussed. [ABSTRACT FROM AUTHOR]

Process‐accompanying derivation of mechanical properties of high‐strength concretes during rapid production The prefabrication of reinforced concrete components bears considerable advantages over conventional in‐situ concrete construction. For instance, an integration of rapid heat treatment allows the processing time in rapid production to be reduced to just a few hours. Treatment time and temperature affect the development of the mechanical properties most. Control of the latter ensures the quality of the components. For concrete components, destructive tests on accompanying samples are common. In this paper, a method is developed with which compressive strength, modulus of elasticity and bond strength can be derived from testing integrated in the production process. The suitability of rebound hammer testing is analysed, taking into account the boundary conditions of heat treatment. Experiments are used to determine the specified target values for the high‐strength Nanodur concrete during production with varying times of heat treatment. The experimental results are compared to the ones derived from standardised correlations. In this way, a model is formed with which primarily the compressive strength and along with it the modulus of elasticity and the bond strength are obtained. The method is discussed against the experimental and theoretical findings. Its application is demonstrated on a simple example and recommendations for checking the mechanical properties in rapid production practically are provided. [ABSTRACT FROM AUTHOR]

Nowadays, composite sheets have been increasingly developed in various applications due to their better corrosion and wear resistance as well as higher strength and formability. Of these, Al/SS bilayer sheets have been used in the food and automotive industries due to their favorable performance and low cost. In this research, the bonding strength of Al1050/AISI304 bilayer sheets fabricated by cold roll bonding has been investigated experimentally. At first, the design of the experiment was carried out using the surface response method, taking into account the thickness of the layers and the rolling reduction ratio, bilayer sheet using the rolling bonding method. In this research, for the first time, the bonding strength of Al/SS bilayer sheets fabricated by cold rolling bonding method and its optimization have been investigated. The bond strength was extracted using T peeling test. Then, using the linear regression method, a mathematical-experimental relationship was presented to obtain the peeling strength in terms of the thickness of the layers and the reduction ratio. The obtained results were analyzed using statistical methods and the table of coefficients, the table of residuals and the analysis of variance table of the data related to bond strength were presented and the adequacy of the presented model was examined. The results showed that by reducing the reduction ratio in the cold rolling process and also reducing the initial thickness of the sheets, the bond strength of the bilayer sheet has decreased. Then, bond strength optimization was done as a function of input parameters. The results indicated that the bonding strength reached its maximum level at the thickness of the aluminum layer = 2 mm, the thickness of the stainless-steel layer = 1.3 mm and reduction = 75%. [ABSTRACT FROM AUTHOR]

This study proposed a linear model between internal bond strength and compressive elastic modulus based on Griffith's fracture theory. The local compressive elastic modulus was determined by non-destructively detecting the inherent frequency of material vibration using a method based on rod longitudinal vibration theory. In the experiment, the inherent vibration frequencies of 10 types of medium-density fiberboard (MDF) were measured through excitation and vibration of piezoelectric ceramics based on longitudinal wave vibration theory. Then, the compressive elastic modulus of each board was calculated. The calculated compressive elastic modulus of MDF and the measured internal bond strength values were fitted into a linear regression model. A high linear correlation between them (r2 = 0.972) was found, having a mean square error of . In addition, the average error between the model prediction value and the measured value was 0.014 MPa, having an average relative error of 1.49%. The maximum error was 0.044 MPa with a maximum relative error of 5.06%, indicating that the developed model was highly consistent with reality and had very small deviations. The results indicated that this proposed method can be used to accurately estimate the internal bond strength by non-destructively detecting the compressive elastic modulus of MDF. [ABSTRACT FROM AUTHOR]

Multicomponent injection molding industry is experiencing a growth due to its ability to reduce production costs and streamline processes. However, compared to single injection, multicomponent injection molding introduces interface regions where multiple engineering polymers meet. Consequently, it is essential to comprehend and enhance the adhesive bonding strength properties of these polymers. This study investigates the adhesive bond strength of polymer-polymer multimaterial molding using two-shot bi-injection and overmolding techniques. The research also emphasizes the influence of injection molding process parameters of mold temperature and melt temperature on the adhesive bond strength of polycarbonate (PC), polycarbonate-acrylonitrile butadiene styrene (PC-ABS), acrylonitrile butadiene styrene (ABS), and styrene ethylene butadiene styrene (SEBS). Tensile strength results revealed that the bi-injection method yields the highest interface strength, approximately 10 MPa lower than the reference value for single-material hard-hard plastics. Results from overmolded samples for both injection sequences are presented, indicating that material with low melting temperature was found to be the first injected part for better adhesion strength. Empirical equations for estimating adhesion strength were derived as a function of interface temperature obtained from CAE numerical simulations and polymer glass transition temperatures. The proposed equation achieved R2 values greater than 0.96. This empirically derived equation will serve as a guide for multi-injection manufacturing processes. [ABSTRACT FROM AUTHOR]

Traditional abradable seal coatings (ASCs) face huge challenges for the requirements of next‐generation aero engines due to high inlet temperature (>1300°C) and non‐matched coefficients of thermal expansion for SiC based composites. Herein, a novel Yb2Si2O7 seal coating was developed to meet the demands of high‐temperature resistance and match the coefficient of thermal expansion with SiC. The prepared Yb2Si2O7 seal coating has excellent properties, including high porosity of 35.5%–23.3%, moderate hardness of 77.9–82.5 HR15Y, and high bond strength of 7.8–9.0 MPa. Adjusting spray current could effectively control the thickness, porosity, and hardness of the coating. More importantly, the coating also has good erosion resistance. Our results show that the fabricated porous Yb2Si2O7 coating would have promising applications in the field of high‐temperature ASCs. [ABSTRACT FROM AUTHOR]

The investigation carried out in this study focused on exploring the hydrogen bonding structure of liquid solutions of methyl lactate and 1-alkanols include 1-butanol, 1-pentanol, 1-hexanol, and 1-heptanol. To analyze the interactions between the molecules, the researcher utilized the cubic-plus-association (CPA) model, which takes into account both the physical and association interactions. The maximum deviation observed in the density of the liquid solutions of methyl lactate with 1-heptanol was 0.28%, indicating the effectiveness of the CPA model in accurately modeling the density. Additionally, the researchers calculated the excess molar volumes and deviation in viscosity for the studied liquid mixtures. The analysis of these measurements revealed that the solutions of methyl lactate with 1-alkanols exhibited positive excess molar volumes across the entire concentration range. On the other hand, negative viscosity deviations were observed for the mentioned alkanols. These findings suggest that there are weak intermolecular associations within the liquid solutions, with weaker bond strength observed in higher alkanols. [ABSTRACT FROM AUTHOR]

Background: Silver diamine fluoride (SDF) has gained popularity for its caries-arresting properties, yet its tendency to cause esthetic concerns due to black-staining limits its widespread acceptance. Aim: The aim of the study was to evaluate and compare the shear bond strength of Activa BioActive and Giomer restorative material with different protocols of SDF pretreatment on carious dentin. Materials and Methods: Ninety-two extracted teeth were decoronated at the cementoenamel junction, sectioned 1 mm into dentin, mounted in acrylic resin and randomly divided into four (n = 8) control and six (n = 10) experimental groups. Seventy-six samples underwent demineralization process for a period of 14 days for artificial carious dentin (ACD) formation. The samples categorized based on the dentin substrate (sound or ACD) were subjected to various SDF pretreatment protocols, i.e., only SDF, SDF with potassium iodide (KI), and SDF with glutathione (GSH). Further, bioactive restorative materials, i.e., Activa BioActive and Giomer (Beautifil II), were placed on it, and the samples were subjected to shear bond strength testing. Statistical Analysis: Independent t -test was run to analyze the values obtained. Results: Giomer exhibited better mean bond strength with SDF, SDF + KI, and SDF + GSH (6.56, 4.67, and 3.34 mega-pascals [MPa], respectively) compared to Activa BioActive (3.42, 3.27, and 2.96 MPa, respectively). Conclusion: This study contributes to understanding the interplay between SDF application protocols, esthetic concerns, and the adhesive properties of bioactive restorative materials. Giomer exhibited enhanced bond strength after SDF application, unlike Activa BioActive. In addition, incorporation of KI or GSH adversely affected the bond strength of both the restorative materials, underscoring the critical need for cautious clinical application. Clinical Relevance: This study highlights the importance of selecting appropriate dentin pretreatment agents to maximize the bond strength of bioactive restorative materials with carious dentin. SDF application significantly enhanced the bond strength of Giomer with carious dentin compared to Activa BioActive, thus, making it a good choice for restoring nonesthetic areas. In addition, the application of KI or GSH to mitigate discoloration of carious dentin negatively affected the bond strength of both, Activa BioActive and Giomer. Thus, the clinicians should weigh the benefits of SDF against potential bond strength reductions when using KI or GSH, especially for esthetic restorations. [ABSTRACT FROM AUTHOR]

Background: Long-term durability of a restoration relies on the marginal integrity and its ability to withstand the occlusal forces. Fiber-reinforced composites (FRCs) exhibited superior properties in terms of fracture toughness, flexural strength, and wear resistance. Aim: The aim of this study was to assess and compare marginal adaptation and microtensile bond strength (µTBS) of posterior FRCs comparing with a condensable composite. Materials and Methods: Standardized mesio- and disto-occlusal cavities were prepared on 60 maxillary molars with 3.5 mm pulpal floor depth, 3 mm buccolingual width, and 1.5 mm axial depth. The mesial cavities were restored with everX Posterior and Build-It FRCs, while distal cavities of all teeth were restored with Alert composite and were thermomechanically aged. Half of the specimens from each group (n = 15) were evaluated for marginal adaptation under scanning electron microscope (SEM), and the other half were sectioned for μTBS testing with Instron testing machine. Bond failure mode was examined under SEM. Results: Marginal microgaps were significantly high for the Alert group than FRC groups. Gingival surface showed more gaps. Mean µTBS values were significantly high for FRCs. Cohesive failures are more among FRCs, and adhesive failures are more in condensable composite. Conclusion: The short FRCs showed superior marginal adaptation and better bond strength than condensable composite. [ABSTRACT FROM AUTHOR]

Background: Bleaching is a conservative treatment option to deliver esthetic smile makeover for discoloured tooth. Various concentration of bleaching agents can influence the bonding of the restoration to the tooth. Aims and Objectives: The aim of the study was to determine the effect of glutathione on bond strength of composite resin to enamel following extra coronal bleaching at two different time intervals. Materials and Methods: Forty molars were randomly assigned into four groups of ten each. Group A: Bleaching followed by immediate composite build up and no antioxidant application. Group B: bleaching followed by application of 20% Glutathione and immediate composite built-up was done. Group C: Bleaching followed by composite restoration after one week. Group D: Bleaching followed by application of 20% Glutathione before composite build up after one week. Shear bond strength was tested using a universal testing machine and fracture analysis was done using scanning electron microscope (SEM). Data were analyzed by one-way ANOVA and Post Hoc test with 95% level of significance (p<0.05). Results: Group D, which was treated with glutathione and restored after one week, revealed the highest shear bond strength compared to group B which was immediately restored following treatment with glutathione. Conclusion: Addition of 20% Glutathione as an antioxidant increased the shear bond strength of composite resin to enamel following extra-coronal bleaching using 40% hydrogen peroxide. [ABSTRACT FROM AUTHOR]

This paper evaluates the binder-aggregate interface during the service life of binders used in chip seal treatments in Brazil based on the perspective of adhesion/cohesion and aggregate loss distress. For this purpose, three materials were selected: two rapid-setting emulsions (unmodified and polymeric) largely recommended for the construction of these coats and a conventional asphalt cement binder of 50–70 penetration, similar to the binder used in the manufacturing of these emulsions. Samples of the binder were aged in the laboratory using two methods: (i) ultraviolet (UV) induced ageing, in a weathering chamber; and (ii) conventional PAV ageing. The bitumen bond strength (BBS) test was used to evaluate adhesion/cohesion in the binder-aggregate interface. It was possible to conclude that ageing mechanisms considerably affect the binders' composition which is reflected in the increase of pull-off tensile strength necessary to break the bond between the binder and aggregate. [ABSTRACT FROM AUTHOR]

Individual behavior of primates living in small groups is often seen to represent behavior of all group members due to close spatial cohesion. However, given that females expend more energy on reproduction than males (including lactation and infant carrying), females and males may exhibit different behaviors even when maintaining spatial proximity, particularly in highly seasonal or resource-poor environments. We collected 187 hours of data from three dyads (n = 6 individuals) of white-handed gibbons (Hylobates lar) living in a fruit-poor environment in western Thailand during the period of fruit scarcity. We calculated activity budgets, dyad behavioral synchronization, and dyad spatial cohesion. We hypothesized that activity budgets would differ significantly between sexes or pairs would engage in behaviors independently to provide females with an opportunity to obtain more resources. We also hypothesized that pairs would remain in close proximity. Overall, activity budgets exhibited significant variation when analyzed by sex (X2 = 27.693, P ⩽ 0.001) and group (X2 = 119.584, P ⩽ 0.001). Females spent less time resting and vocalizing and more time traveling compared to males. Percentages of synchronized behavior were lower than expected with only 55% of records synchronized (group B: 58.6%; group D: 58.5%; group L: 49.7%). Spatial cohesion, however, was relatively high overall with adults in the same or adjacent trees in 67.1% of paired records but significantly variable across groups (B: 89.4%; D: 73.1%; L: 48.2%; X2 = 190.111, P ⩽ 0.001). We suggest that behavioral synchronization and spatial cohesion may be indicators of pair bond strength, not just the result of pair living. Given differences in activity budgets, low behavioral synchronization, and variable amounts of time pair mates spent apart, we conclude that pair mates should be considered individual actors who engage in behaviors independently from one another, particularly when coping with challenging ecological conditions. [ABSTRACT FROM AUTHOR]

This study delves into the nature of individual hydrogen bonds and the relationship between metal cations and hydrogen bonding in the Watson–Crick guanine–cytosine (GC) base pair and its alkali and alkaline earth cation‐containing complexes (Mn+–GC). The findings reveal how metal cations affect the nature and strength of individual hydrogen bonds. The study employs interacting quantum atoms (IQA) analysis to comprehensively understand three individual hydrogen bonds within the GC base pair and its cationic derivatives. These analyses unveil the nature and strength of hydrogen bonds and serve as a valuable reference for exploring the impact of cations (and other factors) on each hydrogen bond. All the H⋯D interactions (H is hydrogen and D is oxygen or nitrogen) in the GC base pair are primarily electrostatic in nature, with the charge transfer component playing a substantial role. Introducing a metal cation perturbs all H⋯D interatomic interactions in the system, weakening the nearest hydrogen bond to the cation (indicated by a) and reinforcing the other (b and c) interactions. Notably, the interaction a, the strongest H⋯D interaction in the GC base pair, becomes the weakest in the Mn+–GC complexes. A broader perspective on the stability of GC and Mn+–GC complexes is provided through interacting quantum fragments (IQF) analysis. This approach considers all pairwise interactions between fragments and intra‐fragment components, offering a complete view of the factors that stabilize and destabilize GC and Mn+–GC complexes. The IQF analysis underscores the importance of electron sharing, with the dominant contribution arising from the inter‐fragment exchange‐correlation term, in shaping and sustaining GC and Mn+–GC complexes. From this point of view, alkaline and alkaline earth cations have distinct effects, with alkaline cations generally weakening inter‐fragment interactions and alkaline earth cations strengthening them. In addition, IQA and IQF calculations demonstrate that the hydration of cations led to small changes in the hydrogen bonding network. Finally, the IQA interatomic energies associated with the hydrogen bonds and also inter‐fragment interaction energies provide robust indicators for characterizing hydrogen bonds and complex stability, showing a strong correlation with total interaction energies. [ABSTRACT FROM AUTHOR]

This study assessed the bond strength of resin‐based restorative materials to fast‐setting calcium silicate cement (Aarhus Uinversity, Denmark) when treated with each of two one‐bottle universal adhesive systems. The cement surface (N = 256) was treated with a self‐priming adhesive and a self‐etch phosphate monomer‐containing adhesive with and without etching of the cement surface. Specimens then received either resin composite or compomer restorative materials (n = 32). The bond strength was measured after 1 day and 1500 thermocycles (n = 16). The failure type was visually inspected. The cement‐adhesive‐restorative material interface was visualized using scanning electron microscopy (SEM). The data were analyzed using multiple linear regression. Restorative material type, resin adhesive system, and thermocycling had a statistically significant effect on the bond strength. Compomer restorative material and self‐etch universal adhesive system demonstrated statistically significantly higher bond strength values to fast‐setting calcium silicate cement, predominantly exhibiting cement cohesive failure. Etching the cement surface enhanced the bond strength of the self‐priming universal adhesive. Thermocycling significantly reduced the bond strength. SEM showed self‐etch universal adhesive seemingly diffused over the etched cement surface compared to other groups. Self‐etch phosphate monomer‐containing universal adhesive and compomer resulted in the highest bond strength to fast‐setting calcium silicate cement. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the shear bond strength (SBS) when bonding a universal resin cement to a disilicate glass‐ceramic using different adhesive protocols. Sixty specimens were etched with 10% hydrofluoric acid (HF) for 20 s and assigned to one of four treatment protocols (n = 15): The Positive control protocol comprised use of a universal adhesive system + adhesive resin cement; the Test1 protocol comprised use of a new universal adhesive system + universal resin cement; the Test2 protocol comprised use of a silane coupling agent + universal resin cement; and the use of a universal resin cement without adhesive and silane served as the Negative control. One of the two resin cement cylinders built on each specimen in each group was used to test for 24‐h SBS, while the other was thermocycled and then tested for SBS. Data were submitted to two‐way ANOVA, Tukey's test, and Weibull analysis. The negative control (24 h) showed the lowest SBS mean value. The Test2 protocol resulted in the highest SBS mean value after thermocycling. Adhesive and mixed failures were prevalent in all groups. No statistical difference in m values was observed among the groups at 24 h. After thermocycling, the two Test protocols showed the highest m values. The m values were significantly lower after thermocycling than at 24 h for all groups. After thermal aging, The Test2 protocol resulted in a statistically significantly higher SBS mean value after thermal aging than seen for the other groups. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Materials and Methods Results Conclusions Clinical Significance To examine the effects of six whitening mouthwashes on tooth color and immediate bond strength to the enamel.Human incisors were divided into seven groups (n = 10) according to mouthwashes (R.O.C.S Black Edition White, Splat White Plus, Colgate Plax White Charcoal, Signal White Now, Listerine Advanced White, Colgate Optic White, and distilled water). After the initial color measurements, the teeth were exposed to mouthwash for 4 weeks. Then, the color measurements were repeated. Then, cylindrical composite resin blocks were immediately applied to the enamel surfaces and subjected to shear bond strength tests. Data were analyzed using Kruskal‐Wallis and Bonferroni tests (α = 0.05).Δ푏, Δ퐿, and ΔE00 values did not present significant differences among the groups. Significant differences among the groups were determined for Δ푎 and ΔWID values (p < 0.05). R.O.C.S Black Edition White and Splat White Plus produced clinically acceptable color changes. Signal White Now, Splat White Plus, and Listerine Advanced White created acceptable whiteness changes. The mouthwashes did not statistically affect the bond strength compared to the distilled water (p > 0.05).Whitening mouthwash containing blue covarine revealed more acceptable color and whitening changes. Mouthwash containing charcoal led to the lowest enamel bond strength values.The content of whitening mouthwashes affected the degree of tooth whitening and shear bond strength to enamel. [ABSTRACT FROM AUTHOR]

AbstractThe second interface of cementing refers to the interface formed by the formation and the cement sheath after cementing. The bonding strength of the second cementing interface is mainly generated through the interaction between the cement sheath and the formation. This study employs sandstone and limestone as experimental materials to investigate the influencing factors on the bonding strength of the second cementing interface by altering the water-cement ratio of the cement slurry system, adding ultrafine materials, and incorporating latex materials. In a progressive experimental approach, various types of cement slurries are selected, including pure cement slurry systems under different water-cement ratios (L1, L2), cement slurry systems with added nano-silica on the basis of pure cement systems (L3), and cement slurry systems with latex added (L4). The influence factors of the bonding strength of the second cementing interface of cement sheaths are explored through self-developed bonding strength evaluation molds and micro-characterization of the bonding interface. The results indicate that increasing the water-cement ratio or adding nano-silica can promote the generation of calcium silicate hydrate (C-S-H), resulting in higher early bonding strength but lower later strength under sandstone interfaces; the reaction of latex particles themselves to form a three-dimensional network structure can enhance the bonding strength. This research provides significant insights into the bonding laws of the second cementing interface and is of great importance to the cementing construction process. [ABSTRACT FROM AUTHOR]