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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]

Background: Radiotherapy is a treatment modality used for head and neck cancer patients. It has a negative influence on bonding strength of adhesives. Little information is available about the effect of radiotherapy on bonding strength of adhesives in primary teeth. Therefore, this in vitro study aimed to detect the best adhesive system and ideal time to apply restorations in primary irradiated teeth regarding adhesive shear bond strength. Methods: Dentin samples from primary teeth were randomly assigned to four groups based on restoration application time and radiation exposure, (G1: control, G2: preradiation, G3: 24 h postradiation, and G4: 6 months postradiation) with 20 samples per group. These groups were further divided into 2 subgroups according to the adhesive system used, with 10 samples per subgroup. (1) 3M™ Single Bond Universal Adhesive (SB), (2) 3M AdperSingle Bond 2 (AS). Samples were exposed to gamma radiation from a cobalt-60 machine. One shot of 60 Gy of radiation was delivered. Then samples were subjected to a shear bond strength test. The load was applied until failure and the maximum load was recorded. Numerical data are presented as mean and standard deviation values, then distributed according to Shapiro–Wilk test or Levene's test and analyzed via two-way ANOVA. The significance level was set at p < 0.05 for all tests. Statistical analysis was performed with R statistical analysis software version 4.4.1 for Windows (Team RC, R: A language and environment for statistical computing. R foundation for statistical computing, 2023). Results: Compared with the AS subgroup, the SB subgroup presented significantly greater values (p < 0.001). For SB, there was no significant difference among the G1 and G4 groups (p > 0.001). However, there was a significant difference between G1, G2, and G3 (p < 0.001, P = 0.025, P = 0.265 ns respectively), and G3 presented the lowest values. For AS, there was no significant difference between groups G1 and G4 (p = < 0.001). Compared with the other groups, G3 presented a significant difference (p = 0.265 ns) and the lowest results. Conclusion: Restorations performed 24 h after radiation had lower bond strength than those performed six months after radiation. Regardless of the adhesive system used, SB performed better than AS in terms of the shear bond strength. [ABSTRACT FROM AUTHOR]

This study aimed to investigate adhesive shear bond strength (SBS) on an ultrafine-grained niobium alloy (UFG-Nb) that is a potential dental implant material. SBS of three adhesive systems combined with three composites to UFG-Nb was compared to corresponding SBS to Ti-6Al-4V and to zirconia. Specimens of the substrates UFG-Nb, Ti-6Al-4V and zirconia with plane surfaces were sandblasted with Al2O3, cleaned and dried. Three adhesive systems (Futurabond U, Futurabond M + , Futurabond M + DCA; all VOCO GmbH, Cuxhaven, Germany) were applied each on specimens of each substrate and light cured. One composite (BifixSE, BifixQM, GrandioSO; all VOCO GmbH) was applied and light cured resulting in 27 groups (n = 10) for all substrate-adhesive-composite-combinations. SBS was measured after 24 h of storage. To simulate aging equally prepared specimens underwent 5000 thermocycles before SBS measurement. There was no significant difference in SBS within the non-aged groups. Among the artificially aged groups, GrandioSO-groups showed a greater variance of SBS than the other composites. All significant differences of corresponding UFG-Nb-, Ti-6Al-4V- and zirconia-groups with same adhesive-composite-combination (ACC) were observed between UFG-Nb and zirconia or Ti-6Al-4V and zirconia but never between the two metallic substrates. The similarity between these materials might show in their adhesive bonding behavior. As there were no differences comparing corresponding groups prior to and after artificial aging, it can be concluded that aging does not affect SBS to UFG-Nb, Ti-6Al-4V and zirconia using the tested ACCs. Adhesive bonding of established ACCs to UFG-Nb is possible resulting in SBS comparable to those on Ti-6Al-4V and zirconia surfaces. [ABSTRACT FROM AUTHOR]

Polymerization shrinkage of bonded resin composite restorations will result in the development of curing contraction stresses during setting and can cause debonding of the restoration or failure of the surrounding tooth structure. However, the hygroscopic expansion that occurs after exposure of the restorative to the wet oral environment can compensate for this shrinkage. The purpose of this study was to determine the hygroscopic expansion of six commercial resin composites and relate it to their composition, mechanical properties, shrinkage, and contraction stress development. Short-term volumetric shrinkage and contraction stress of the different composites were measured by mercury dilatometry and a universal testing machine. The long-term contraction stress was measured by the deflection of a bilayer strip of metal and a resin composite, which were stored dry as well as wet to determine the effect of hygroscopic expansion. The curvature of the strip was measured by profilometry over a period of 3 months. The curvature of the strip correlated well (r2 =0.74) with the initial contraction stress, showing that the contraction stress is an important factor in initial deformation. The water sorption in all specimens showed that the initial deformation, within 2–4 weeks after curing, was completely counteracted. A high correlation (r2 =0.90) between deflection and relative water sorption was found, where the relative water sorption is defined as the absolute water sorption corrected for the inorganic filler volume of the composite. Within a period of 2–4 weeks after curing most of the curing contraction stresses of resin composite restoratives will be released by hygroscopic expansion. [ABSTRACT FROM AUTHOR]

The biodegradation of methacrylate (MA)-based dental restoratives has been suggested to contribute to a loss of adhesion and subsequent detachment, or secondary caries, both major causes of restoration failure. Previous studies have demonstrated that intermolecular interactions between resin monomers may affect the hydrolytic-susceptibility of composites. Altering the intermolecular interactions by shielding or masking the hydrolytically-susceptible ester groups found in MA monomers could be an effective strategy to mitigate the biodegradation of resin composites. The objective of this work was to assess whether shielding/masking MAs using fluorinated groups could improve the biostability of experimental composites. Eight fluorinated monomers (FM) were synthesized, characterized (1H NMR), and formulated into experimental resin composites (FC, 65 wt%, microfill). FCs were assessed for interactions with water (water contact angle, water sorption, gel fraction), mechanical properties (both compressive and flexural strength and modulus), cytocompatibility, resistance to biodegradation using simulated human salivary esterase (SHSE) and compared to a control composite (CC) without FM. Integration of FMs was found to generally decrease both the physical and mechanical properties under all incubation conditions when compared to the CC. Additionally, all FCs had a negative influence on composite biodegradation following immersion in SHSE when compared to the CC. Shielding/masking MA-esters inherently inserts molecular spaces between the polymer chains within the resin network, and shielding is likely not possible while also maintaining the necessary cohesive forces that regulate the physical and mechanical properties of resin composites. Novel dental resin development should seek to remove/replace vulnerable ester-containing MAs rather that adopting a shielding/masking approach. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the shear bond strength (SBS) of resin composite to dentin contaminated with artificial saliva (AS) containing mucin and amylase using an experimental method controlling the volume of saliva and adhesive in a defined surface area. Methods: Flat bonding surfaces were prepared on extracted human molars (320 grit surface). Using adhesive tape, a 4.5 mm bonding window was prepared on the dentin surfaces. Groups (n= 12) were prepared using the etch & rinse (ER) or self-etch (SE) modes for Adhese Universal (ADH), Scotchbond Universal Plus (SBU), and Prime & Bond active (PBA) dental adhesives (DA). For the control (C) groups, the adhesives were applied per the manufacturers' instructions with 2.0 μl or 3.0 μl of the adhesive. For the saliva-contaminated groups, 1.0 μl of artificial saliva with mucin was applied in the bonding window either dried or allowed to remain wet before the application of either 2.0 μl or 3.0 μl of the adhesive. After the adhesive film was air dried and light cured using an Ultradent bonding fixture, Spectrum TPH3 was bonded to the prepared surfaces. After water storage for 24 hours at 37oC, the specimens were debonded and shear bond strength (SBS) was calculated (MPa). A Kruskal-Wallis test with Bonferroni correction was used to determine group differences (P< 0.05). Scanning electron microscopy (SEM) was performed to visualize the interfacial surfaces prepared using an ion-etching technique. Results: Mean SBS for the three adhesives were similar in both ER and SE modes to Uncontaminated dentin surfaces for all the control groups. For dentin contaminated with dried or wet saliva, both the surface condition and the adhesive system were significant factors at a confidence level of 95%. For the dried saliva test groups, ADH and PBA with 3.0 μl of adhesive generated similar SBS values to controls while SBU generated lower values. Lower values were generated when using 2.0 μl of adhesive for the three adhesives in SE and ER modes except for PBA in the ER mode. Using wet saliva and 3.0 μl of adhesive ADH and SBU generated lower SBS values while PBA generated similar values to controls. Under SEM, morphology at the adhesive dentin interfaces was similar among the adhesives to uncontaminated dentin but notable differences were observed for SBU and ADH for both wet and dried saliva-contaminated surfaces. [ABSTRACT FROM AUTHOR]

The central aim of adhesive dentistry is to improve the compatibility between current adhesives and a range of substrates by employing diverse application techniques. Therefore, the overarching objective of this review is to offer a comprehensive analysis of dentin bonding systems, starting with an introduction to adhesion and a detailed overview of enamel and dentin structures, their histology, and the impact of dentin structure on resin–dentin bonding. It covers the mechanisms of resin–dentin bonding, including resin adhesive application, bonding mechanisms, and factors influencing efficacy. Further, this review explores the composition of resin adhesive systems, including acidic components, cross-linking monomers, solvents, and other critical elements. It also examines various adhesive strategies—etch-and-rinse, self-etch, and universal adhesives—highlighting their applications and advantages. The review extends to clinical applications of dental adhesion, including direct restorations, indirect restorations, and immediate dentin sealing (IDS), demonstrating the practical implications of adhesive systems in enhancing restoration longevity and performance. In conclusion, despite significant advancements, no gold-standard method for optimal adhesion exists. Each adhesive system has distinct strengths and limitations. The review emphasizes the importance of evaluating methods for achieving durable adhesion and staying current with technological advancements in adhesive systems. Summary: This review provides a thorough analysis of dentin bonding systems, delving into the structures and bonding mechanisms of both enamel and dentin. By exploring various adhesive systems and their components, it highlights the ongoing challenges in achieving optimal resin–dentin adhesion. The review also addresses the clinical applications of dental adhesion, including direct restorations, indirect restorations, and immediate dentin sealing (IDS), illustrating how different adhesive techniques impact clinical outcomes. It underscores the necessity for continuous innovation and assessment of adhesive systems to enhance long-term bonding effectiveness in clinical practice. [ABSTRACT FROM AUTHOR]

Bioactive glasses are renowned for their applications in dentistry, serving as restorative materials, dental adhesives, intracanal medicaments, and agents for enamel remineralization. Niobium pentoxide (Nb 2 O 5) is employed in dental adhesive resins and orthodontic adhesives, offering radio-pacifying properties essential for dental materials. Samarium oxide (Sm 2 O 3) emerges as a potential additive in aesthetic restorative dental ceramics and resins, enhancing the natural fluorescence of teeth. In this study Nb 2 O 5 and Sm 2 O 3 -doped (1, 3, and 5 wt%) 13–93 bioactive glass particles were synthesized via the sol-gel method, tailored for dental implementations. We conducted a comprehensive analysis of the physical, structural, and optical properties of the resultant glass powders. Additionally, their in vitro bioactivity and ionizing radiation shielding characteristics were rigorously evaluated. The results indicate that Sm3+ ions preserve the amorphous nature of the silicate glasses, while Nb5+ incorporation leads to the crystallization of the T-Nb 2 O 5 phase. Bioactivity assays across three physiological fluids—simulated body fluid, α-minimum essential medium, and phosphate-buffered saline, demonstrated the ability of doped glasses to facilitate hydroxyapatite layer formation, with the most pronounced bioactivity observed in phosphate-buffered saline immersed samples. Furthermore, radiation shielding simulations reveal that the addition of Nb 2 O 5 and Sm 2 O 3 enhances the ionizing radiation attenuation capabilities of the glasses, a property that holds significant promise for protecting against radiation in dental radiology. It can be concluded that the dual functionality of Nb5+ and Sm3+-doped bioactive glasses, which may revolutionize restorative dental practices and offer improved protection in radiological applications. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the mechanical behavior of resin composites and hybrid glass ionomer cement in class I adhesive dental restorations under loading and shrinkage conditions. Three CAD models of a mandibular first molar with class I cavities were created and restored with different techniques: a bi-layer of Equia Forte HT with Filtek One Bulk Fill Restorative composite (model A), a single layer of adhesive and Filtek One Bulk Fill Restorative (model B), and a single layer of Equia forte HT (model C). Each model was exported to computer-aided engineering software, and 3D finite element models were created. Models A and B exhibited a similar pattern of stress distribution along the enamel–restoration interface, with stress peaks of 12.5 MPa and 14 MPa observed in the enamel tissue. The sound tooth, B, and C models showed a similar trend along the interface between dentine and restoration. A stress peak of about 0.5 MPa was detected in the enamel of both the sound tooth and B models. Model C showed a reduced stress peak of about 1.2 MPa. A significant stress reduction in 4 mm deep class I cavities in lower molars was observed in models where non-shrinking dental filling materials, like the hybrid glass ionomer cement used in model C, were applied. Stress reduction was also achieved in model A, which employed a bi-layer technique with a shrinking polymeric filling material (bulk resin composite). Model C's performance closely resembled that of a sound tooth. [ABSTRACT FROM AUTHOR]

The present work demonstrates the optimization of a renilla-based real-time, ultra-bright, non-disruptive, high-throughput bioluminescence assay (HTS) to assess the metabolism of intact Streptococcus mutans biofilms and its utility in screening the antibacterial efficacy of experimental nanofilled dental adhesive resins containing varying concentrations of nitrogen-doped titanium dioxide nanoparticles (N_TiO 2). Methods. Optimization of the assay was achieved by screening real-time bioluminescence changes in intact Streptococcus mutans biofilms imposed by the various experimental biofilm growth parameters investigated (bacterial strain, growth media, sucrose concentration, dilution factor, and inoculum volume). The optimized assay was then used to characterize the antibacterial efficacy of experimental nanofilled dental adhesive resins. The assay's ability to discriminate between bacteriostatic and bactericidal approaches was also investigated. Results. Relative Light Units (RLU) values from the HTS optimization were analyzed by multivariate ANOVA (α = 0.05) and coefficients of variation. An optimized HTS bioluminescence assay was developed displaying RLUs values (brightness) that are much more intense when comparing to other previously reported bioluminescence assays, thereby decreasing the error associated with bioluminescence assays and displaying better utility while investigating the functionalities of antimicrobial nanofilled experimental dental adhesive resins with proven long-term properties. Significance. The present study is anticipated to positively impact subsequent research on dental materials and oral microbiology because it serves as a valuable screening tool in metabolic-based assays with increased sensitivity and robustness. The assay reported is anticipated to be further optimized to be used as a co-reporter for other Luc based assays. [ABSTRACT FROM AUTHOR]

Currently, the issue of increased dentin sensitivity after operations for hard dental tissue preparation during the therapeutic treatment of the carious process, as well as during orthopedic treatment of various types with non-removable dentures, has retained its relevance. Pain management is the prevention of postoperative complication development and ensures high-quality treatment results. Aim. The purpose of the literature review in this paper was to draw specialists' attention to the use of low-solvent adhesive systems of various types to manage postoperative sensitivity of hard dental tissues. Materials and methods. More than 30 literature sources focused on studying action mechanisms of known generations of dental adhesive systems and their effects on changes in postoperative sensitivity of dental hard tissues as a result of a high-quality protective film formation on the dentin surface have been analyzed. Results. The use of various adhesive systems to reduce postoperative sensitivity of soft tissues with the formation of a high-quality protective film on the dentin surface that seals the dentinal tubules is of great importance for obtaining qualitative treatment results and increasing its effectiveness. However, various reactive substances (solvents, acetone), which are components of most adhesives, have a strong impact on their quality and significantly reduce the indications for their use. Conclusions. Thus, studying the action mechanisms of adhesives on dental tissues, searching for the formulation of new adhesive systems with a lower solvent content would expand the indications for their use as therapeutic and prophylactic drugs to reduce pain sensitivity of hard dental tissues after preparation. [ABSTRACT FROM AUTHOR]

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Objective This study aims to evaluate the bond strength of polyetheretherketone (PEEK) and polyetherketoneketone (PEKK) materials when used as substructures with composite superstructures, before and after artificial aging. Surface treatments, including sanding and sandblasting, were examined to determine their impact on bond strength and surface topography. Materials and Methods Sixty samples, divided equally between PEEK and PEKK, were prepared. Each group was further divided into three subgroups (n = 10): control, 10,000 thermal cycles, and 30,000 thermal cycles. The samples were subjected to surface treatments using 600-, 800-, and 1,200-grit silicon carbide wet sandpaper, followed by air abrasion with 110 µm alumina particles. Bond strength tests were conducted using an INSTRON-3345 universal testing machine, and failure types were analyzed under a stereomicroscope. Results Sandblasting with 110 µm aluminum oxide (Al 2 O 3) significantly increased the bond strength of both PEEK and PEKK materials compared with sanding. PEEK samples treated with sandblasting showed the highest bond strength (mean = 1.296 MPa), while PEKK samples treated with sanding had the lowest (mean = 0.056 MPa). Thermal cycling reduced bond strength in both materials, with a more pronounced decrease observed in the 30,000 cycle groups. analysis of variance results indicated significant differences in bond strength based on the material, surface treatment, and the interaction between these factors. Conclusion Sandblasting with 110 µm Al 2 O 3 is an effective method for enhancing the bond strength of PEEK and PEKK substructures with composite materials. These findings support the continued use of PEEK and PEKK polymers in dental applications, suggesting that appropriate surface treatments can significantly improve clinical outcomes. [ABSTRACT FROM AUTHOR]

This systematic review aims to evaluate whether the application of antioxidant solutions can enhance the bond strength of resin-based materials to sodium hypochlorite (NaOCl)-treated dentin. This study follows the PICOT strategy: population (sodium hypochlorite-treated dentin), intervention (application of antioxidants), control (distilled water), outcome (bond strength), and type of studies (in vitro studies). The systematic review and meta-analysis were conducted following PRISMA guidelines. Electronic databases were searched for in vitro studies evaluating the effects of antioxidants on bond strength to sodium hypochlorite-treated dentin. Two independent reviewers screened articles, extracted data, and assessed risk of bias. Meta-analyses were performed using a random-effects model to compare standardized mean differences in bond strength between antioxidant pretreatment and control groups. Inclusion criteria consisted of in vitro studies that examined the bond strength of resin-based materials to NaOCl-treated dentin with antioxidant application, while exclusion criteria included studies with incomplete data, those not using a control group, or those that did not directly measure bond strength. From 3041 initial records, 29 studies were included in the qualitative analysis and 25 in the meta-analysis. Ascorbic acid, sodium ascorbate, grape seed extract, green tea, and rosmarinic acid significantly improved bond strength to sodium hypochlorite-treated dentin (p < 0.05). The effectiveness of grape seed extract varied with adhesive system type. Hesperidin, p-toluene sulfonic acid, and sodium thiosulfate did not significantly improve bond strength. Most studies had a high risk of bias. This suggests that the conclusions drawn from these studies should be interpreted with caution, and further research with more robust methodologies may be needed to confirm the findings. In conclusion, this systematic review implies that certain antioxidants can improve bond strength to sodium hypochlorite-treated dentin, with efficacy depending on the specific agent and adhesive system used. Further standardized studies are needed to optimize protocols and confirm these findings. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate dental adhesives containing different concentrations of zinc oxide nanoparticles (ZnO‐NPs) for their use in the treatment of dental fluorosis, observe the interaction of the adhesive on healthy enamel surfaces and with mild and moderate fluorosis, measure the adhesive strength and fluorosis, and determine the phosphorus (P) and calcium (Ca) content on these surfaces, as a reference for the potential use of this adhesive with ZnO‐NPs for dental fluorosis treatment.Transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) were used to characterise the ZnO‐NPs and analyse the weight percentages of P and Ca in the enamel using X‐ray energy dispersive spectroscopy (EDS) and the adhesive strength using a universal mechanical testing machine.FESEM characterisation revealed that the ZnO‐NPs were less than 100 nm in size, with quasi‐spherical and hexagonal prism shapes. The synthesis of the ZnO‐NPs was confirmed by TEM, revealing their hexagonal crystalline structure. The adhesive strength by the universal mechanical testing machine showed that the adhesive with a 3% wt. concentration of ZnO‐NPs was better in the three groups of teeth, showing higher adhesive strength in teeth with mild (15.15 MPa) and moderate (12.76 MPa) fluorosis surfaces, and was even higher than that in healthy teeth (9.65 MPa).EDS analysis showed that teeth with mild and moderate fluorosis had the highest weight percentages of P and Ca, but there were no statistically significant differences compared to healthy teeth and teeth treated with adhesives.Lay description: This study focused on testing a new dental adhesive containing small particles called ZnO nanoparticles (ZnO‐NPs). This study aimed to demonstrate whether this adhesive with ZnO‐NPs could be useful for treating dental fluorosis by improving its adhesion to teeth.One of the first objectives was to determine whether the dental adhesive could adhere better to teeth affected by mild or moderate fluorosis than to healthy teeth by measuring whether the levels of two important elements for healthy teeth, calcium (Ca) and phosphorus (P), were affected by the adhesive.The size and shape of the small particles and teeth with mild or moderate fluorosis were observed using scanning electron microscopy. The nanoparticles were small (< 100 nm) and had specific quasi‐spherical and hexagonal prismatic shapes. More damage to the enamel was observed in teeth with mild or moderate fluorosis than in healthy teeth.The adhesive strength test demonstrated that the dental adhesive with 3% ZnO‐NPs had the best adhesion on all healthy conditions of teeth. It was particularly effective in teeth with mild or moderate fluorosis.Finally, the evaluation of the levels of P and Ca on the enamel showed that teeth with fluorosis had higher levels of these elements, but using the dental adhesive with ZnO‐NPs did not change the levels of these elements significantly because the adhesive avoided greater detachment because of greater adhesion to these surfaces.In conclusion, adding these small particles to dental adhesives could be an option for treating teeth affected by fluorosis. It stuck well and did not affect the levels of the important elements in the teeth. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical efficacy of novel titania-nanoparticle reinforced bonding agent on post-restorative sensitivity in patients. Methods: This triple-blinded, randomized clinical trial included participants (n = 60) having Class- I and II cavitations with a minimum cavity depth of 3mm at Department of Operative Dentistry & Endodontics, School of Dentistry, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad from January 5, 2023, to June 20, 2023. They were randomly assigned into two groups A and B (n = 30). After informed consent, restorative intervention was accomplished using an etch-and-rinse adhesive strategy. In Group-A, titania-nanoparticle-incorporated bonding agent was used for composite restoration, while in Group-B, bonding agent without nanoparticles was used. The primary outcome was assessed using Visual Analogue Scale mean score. Participants were instructed to rate their sensitivity status at follow-ups: 24 hours, one week, and one month. Mann-Whitney U test was employed to compare sensitivity between the two groups. Results: According to results of this trial, a significant difference was observed between two groups after 24 hours (p = 0.004) and one week (p = 0.002). However, no discernible difference was observed after one month (p = 0.643). Conclusion: Post-restorative sensitivity in patients with composite restorations was reduced using titania-reinforced bonding agents as compared to bonding agents without nanoparticles. This shows that inclusion of titania nanoparticles into adhesive dentistry could be beneficial in resolving post-restorative sensitivity occurring with composite restorations. [ABSTRACT FROM AUTHOR]

(1) Background: The in vitro study aimed to investigate mechanical characteristics of resin composites and their suitability in direct restauration of endodontically treated teeth (ETT). (2) Methods: 38 endodontically treated premolars with occlusal access cavities were directly restored using the following resin composites and adhesives: Tetric Evo Ceram® + Syntac classic® (n = 10), Venus Diamond® + iBond Total-Etch® (n = 10), Grandio® + Solobond M® (n = 9), Estelite® Sigma Quick + Bond Force® (n = 9). After thermocycling, the elastic modulus, shear-bond-strength, fracture load (Fmax) and fracture mode distribution were evaluated. Statistical analysis: one-way ANOVA, t-test, Kruskal–Wallis test; p < 0.05. (3) Results: Grandio® showed the highest E-modulus (15,857.9 MPa) which was significant to Venus Diamond® (13,058.83 MPa), Tetric Evo Ceram® (8636.0 MPa) and Estelite® Sigma Quick (7004.58 MPa). The highest shear-bond-strength was observed for Solobond M® (17.28 MPa), followed by iBond® (16.61 MPa), Syntac classic® (16.41 MPa) and Bond Force® (8.37 MPa, p < 0.05). The highest fracture load (Fmax) was estimated for ETT restored with Venus Diamond® (1106.83 N), followed by Estelite® Sigma Quick (1030.1 N), Tetric Evo Ceram® (1029 N) and Grandio® (921 N). Fracture-mode distribution did not show any significant differences. (4) Conclusions: The observed resin composites and adhesives show reliable mechanical characteristics and seem to be suitable for direct restoration of endodontically treated teeth. [ABSTRACT FROM AUTHOR]

Hydrolytically and enzymatically-stable multi-acrylamides have been proposed to increase the long-term durability of dental adhesive interfaces as alternatives to methacrylates. The aim of this study was to investigate the mechanical and biochemical properties of experimental adhesives containing multi-functional acrylamides concerning collagen reinforcement and metalloproteinases (MMP) activity. Multi-functional acrylamides, TMAAEA (Tris[(2-methylaminoacryl) ethylamine) and DEBAAP (N,N-Diethyl-1,3-bis(acrylamido) propane), along with the commercially available DMAM (N,N-dimethylacrylamide) (monofunctional acrylamide) and HEMA (2-Hydroxyethyl methacrylate) (monofunctional methacrylate - control) were tested for stability against enzymatic hydrolysis by cholesterol esterase/pseudocholinesterase (PC/PCE) solutions for up to 30 days. Collagen-derived substrate and gelatin zymography were performed to examine the effect of the compounds on the biological activity of human recombinant and dentin-extracted gelatinases MMP-2 and MMP-9. In situ zymography was carried out by fluorescent collagen degradation combined with confocal microscopy analysis. Hydroxyproline content was measured in collagen derived from dentin extracts though reaction with Ehrlich's reagent p -dimethylaminobenzaldehyde (DMAB), generating a stable chromophore measured at 550 nm. Storage shear modulus of demineralized dentin discs treated with the tested compounds was measured by oscillatory rheometry, in order to investigate potential collagen reinforcement. FT-IR was performed to determine qualitative differences in collagen based on observed changes in amide bands. The results were analyzed by ANOVA/Tukey's test (α = 0.05). Multi-acrylamides survived 30 days of incubation in cholinesterase/pseudo-cholinesterase (PC/PCE) solutions, while HEMA showed approximately 70 % overall degradation. Incubation with multi-acrylamides reduced collagen degradation as evidenced by the reduced hydroxyproline levels and by the 30 % increase inshear storage modulus. Biochemical and zymography assays showed no noticeable inhibition of recombinant and extracted MMPs enzymatic activity. The infra-red spectroscopy results for multi-functional acrylamides treated samples demonstrated shifts of the amide II bonds and marked increase in intensity of the bands 1200 cm-1, which may indicate partial collagen denaturation and some degree of cross-linking of the compounds with collagen, respectively. The multi-acrylamides exhibited not only comparable mechanical properties but also demonstrated significantly enhanced biochemical stability when compared to the widely used methacrylate control. Clinical relevance: These findings highlight the potential of multi-acrylamides to increase the bonding stability to tissues and, ultimately, contribute to the longevity of dental restorations. [ABSTRACT FROM AUTHOR]

Context: Traditional conductive adhesives based on epoxy resin system often encounter problems such as high brittleness and low heat resistance. Therefore, it is particularly important to improve the thermal and mechanical properties of the conductive adhesive. In this study, the effects of SWCNT-Ag and SWCNT fillers on the thermal properties of DGEBA/DETA/Ag conductive adhesive system were studied by using molecular dynamics to construct different cross-linking models. The final results show that the addition of SWCNT and SWCNT-Ag can significantly improve the thermal properties of the conductive adhesive. However, the nanosilver particles on the surface of SWCNT-Ag act as a bridge for the connection between SWCNT and Ag in the conductive adhesive. Therefore, SWCNT-Ag has a more positive impact on the thermal properties of DGEBA/DETA/Ag conductive adhesive system. Methods: In this paper, the influence of SWCNT-Ag on the thermal properties of traditional DGEBA/DETA/Ag conductive adhesive system was studied by using Materials Studio software. The volume shrinkage, glass transition temperature, thermal expansion coefficient, and thermal conductivity of the material were calculated based on COMPASS force field. The thermal conductivity is calculated by using reverse non-equilibrium molecular dynamics method. Finally, it is found that SWCNT-Ag has a positive effect on the thermal properties of the conductive adhesive system by comparing several groups of calculation data. [ABSTRACT FROM AUTHOR]

This study evaluated improvements in the micro-tensile bond strength of a one-bottle adhesive to dentin upon incorporating a thiol compound. Formulations containing 0, 0.1, 0.3 or 0.5% of the thiol were prepared (TH78-0, TH78-0.1, TH78-0.3 and TH78-0.5). Flat dentin surfaces were produced on non-carious extracted human molars using a diamond saw and 600 grit SiC paper. Each surface was subsequently treated with one of the four experimental adhesives or a commercially available adhesive (Scotchbond Universal Adhesive), following the manufacturers' instructions. A resin composite was then incrementally built on the adhesive-treated surfaces and light-cured, after which the bonded specimens were sectioned and subjected to micro-tensile bond strength tests. Bond strengths ranging from 28.7 MPa (for the TH78-0.5) to 45.9 MPa (for the TH78-0.1) were obtained from the experimental specimens, whereas the commercial adhesive showed a strength of 36.9 MPa. A 0.1% thiol concentration therefore increased the baseline bonding of the adhesive and gave the highest strength, with significantly decreased values in the cases of 0.3% and 0.5% concentrations. [ABSTRACT FROM AUTHOR]

Molasses can serve as a natural adhesive for plywood and particleboard. However, several disadvantages remain, including lower dimensional stability and low bonding strength compared to other adhesives. Therefore, modifications are needed to use molasses as an adhesive for plywood. This research aims to improve bio-based molasses (MO) adhesive for plywood using citric acid (CA) adhesive. In addition, this research aims to analyze the effect of adding citric acid and to investigate the optimum hot-pressing temperature to produce the best quality plywood. In the first stage, the molasses and citric acid were combined in a ratio of 100:0, 75:25, 50:50, 25:75, 0:100 w/w%. Then, the second stage focuses on analyzing the influences of pressing temperature based on an optimum first stage. The research demonstrated that the addition of CA altered the gelation time, solid content, viscosity, and pH of the molasses adhesives. In addition, the thermal properties of molasses adhesives were changed after mixing with citric acid. These phenomena indicate changes in characteristics, such as the curing of adhesive. Overall, the characteristics of plywood showed a steady improvement as the CA ratio increased but revealed a significant decline for the 25:75 MO-CA ratio. By raising the pressing temperature from 180°C to 200°C, the quality of plywood was effectively improved. The plywood that was bonded using adhesives with a 50:50 MO-CA ratio exhibited superior mechanical properties and improved dimensional stability compared to the plywood bonded solely with MO. Furthermore, the optimal mechanical and physical properties resulted in plywood bonded with a 50:50 MO-CA ratio when subjected to a pressing temperature of 200°C. The Thermal and FTIR measurements revealed that CA established ester bonds with both the MO and wood veneers. In conclusion, the mechanical characteristics of plywood were improved, while maintaining its excellent dimensional stability. [ABSTRACT FROM AUTHOR]

Currently, the issue of increased dentin sensitivity after operations for hard dental tissue preparation during the therapeutic treatment of the carious process, as well as during orthopedic treatment of various types with non-removable dentures, has retained its relevance. Pain management is the prevention of postoperative complication development and ensures high-quality treatment results. Aim. The purpose of the literature review in this paper was to draw specialists’ attention to the use of low-solvent adhesive systems of various types to manage postoperative sensitivity of hard dental tissues. Materials and methods. More than 30 literature sources focused on studying action mechanisms of known generations of dental adhesive systems and their effects on changes in postoperative sensitivity of dental hard tissues as a result of a high-quality protective film formation on the dentin surface have been analyzed. Results. The use of various adhesive systems to reduce postoperative sensitivity of soft tissues with the formation of a high-quality protective film on the dentin surface that seals the dentinal tubules is of great importance for obtaining qualitative treatment results and increasing its effectiveness. However, various reactive substances (solvents, acetone), which are components of most adhesives, have a strong impact on their quality and significantly reduce the indications for their use. Conclusions. Thus, studying the action mechanisms of adhesives on dental tissues, searching for the formulation of new adhesive systems with a lower solvent content would expand the indications for their use as therapeutic and prophylactic drugs to reduce pain sensitivity of hard dental tissues after preparation.

Objective: This systematic review evaluated how different storage times and conditions affect universal adhesives' bond strength and degree of conversion (DC).Methods: A literature search was conducted in PubMed, Scopus, Web of Science, and Google Scholar databases for articles published from January 1st, 2000, until May 15th, 2022. The researchers comprehensively evaluated the articles using a multi-step process to identify articles relevant to the topic of interest. Quality assessment was performed through the ROBDEMAT tool. Due to the high heterogeneity in the preliminary data, performing a meta-analysis was not feasible.Results: A total of 3169 records were obtained, and after removing duplicates, 2267 remained. Following title and abstract screening, 2253 studies were excluded based on the predetermined exclusion criteria. Of the 14 remaining studies, seven were further excluded due to the use of non-universal adhesives, experimental adhesives, or lack of aging protocols. Ultimately, seven studies were included in this systematic review. All studies focused on bond strength, with only one addressing DC. The Findings showed that aging or different storage conditions generally led to reduced bond strength and DC values in universal adhesives, although exceptions with stable or improved properties were noted.Conclusions: Adhesives with higher pH and those containing methacrylamides, HEMA-free compositions, or hydrolytically stable monomers showed better durability than others. Strict adherence to storage instructions, lower storage temperatures, and immediate recapping of adhesive bottles after use is recommended to maintain adhesive properties. These findings provide insights for optimizing the long-term performance of universal adhesives in clinical settings.

Objective: This study investigated the effect of casein phosphopeptide‑amorphous calcium phosphate (CPP‑ACP) on the shear bond strength (SBS) of a universal adhesive in self-etch mode to demineralized dentin.Methods: Seventy-five dentin specimens were randomly divided into five groups (n=15) as follows: Group 1, intact dentin; Group 2, demineralized dentin receiving no remineralization agent; and Groups 3-5, demineralized dentin receiving CPP-ACP for 30, 90, and 180 seconds, respectively. All groups were bonded by Adper Single Bond Universal adhesive in self-etch mode. After 24 hours, the SBS test was conducted, and failure modes were recorded. The data were analyzed by one-way ANOVA, Tukey post-hoc test, and chi-square test at the significance level of P

Abstract This preregistered ex vivo investigation examined the dentinal hybrid layer formation of a resinous infiltrant (Icon), with reference to both thickness (HLT) and homogeneity when combined with modified tunnel preparation (occlusal cavity only) and internal/external caries infiltration. The adhesives Syntac and Scotchbond MP were used as controls (Groups 1 and 3) or in combination with Icon (Groups 2 and 4). A split-tooth design using healthy third molars from 20 donors resulted in 20 prepared dentine cavities per experimental group. The cavity surfaces (n = 80) were etched (37% H3PO4), rinsed, and air-dried. Rewetting with ethanol was followed by application of the respective primers. After labeling with fluorescent dyes, either Syntac Adhesive/Heliobond or Scotchbond MP Adhesive was used alone or supplemented with Icon. HLT, as evaluated by scanning electron microscopy, did not significantly differ (P > 0.05), and confocal laser scanning microscopy revealed homogeneously mixed/polymerized resin-dentine interdiffusion zones in all groups. Icon can be successfully integrated into an ethanol-wet dentine bonding strategy, and will result in compact and homogeneous hybrid layers of comparable thickness considered equivalent to the non-Icon controls, thus allowing for preservation of the tooth’s marginal ridge and interdental space in the case of internal/external infiltration of proximal caries.

This study evaluated the biocompatibility, bioactivity, porosity, and sealer/dentin interface of Sealer Plus BC (SP), Bio-C Sealer (BIOC), TotalFill BC Sealer (TF), and AH Plus (AHP). Dentin tubes filled with the sealers and empty tubes (control group) were implanted in the subcutaneous tissue of rats for different periods (n = 6 per group/period). Number of inflammatory cells (ICs), capsule thickness, von Kossa reaction, interleukin-6 (IL-6) and osteocalcin (OCN) were evaluated. Porosity and voids in the interface dentin/sealers were assessed by micro-computed tomography. The data were submitted to ANOVA/Tukey's tests (α = 0.05). Greater capsule thickness, ICs and IL-6 immunolabeling cells were observed in AHP. No significant difference in thickness of capsule, ICs, and IL-6- immunolabeling cells was detected between SP and TF, in all periods, and after 30 and 60 days between all groups. At 60 days all groups had reduction in capsule thickness, ICs and IL-6 immunolabeling cells. Von Kossa-positive and birefringent structures were observed in the capsules around the sealers. BIOC, SP, and TF exhibited OCN-immunolabeling cells. All sealers had porosity values below 5%, besides low and similar interface voids. BIOC, SP and TF are biocompatible, bioactive, and have low porosity and voids. The dentin-tube model used is an alternative for evaluating bioceramic materials. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the microleakage of light-cured and self-cured adhesives on enamel surfaces selectively etched with Er, Cr: YSGG laser or 35% phosphoric acid. A total of 60 class V cavities were prepared 1 mm above the cemento-enamel junction (CEJ). The specimens were randomly divided into six groups. Group 1: Clearfil SE Bond with no conditioning, Group 2: Tokuyama Universal Bond with no conditioning, Group 3: Clearfil SE Bond conditioned with 35% phosphoric acid, Group 4: Tokuyama Universal Bond conditioned with 35% phosphoric acid, Group 5: Clearfil SE Bond conditioned with Er, Cr: YSGG laser and Group 6: Tokuyama Universal Bond conditioned with Er, Cr: YSGG laser. Microleakage was evaluated qualitatively (visually) and quantitatively (ImageJ). The data were analyzed using IBM SPSS V23 and submitted to Kruskal–Wallis and Wilcoxon tests. The significance level was set at p < 0.05. In all evaluation methods, the microleakage scores exhibit significant differences (p*<0.001). Group 1 and Group 3 exhibited similar and lower microleakage values than the Group 5. In the occlusal margin, the microleakage values were similar in Group 2, Group 4, and Group 6, whereas in the gingival margin Group 4 showed significantly lower leakage compared to Group 2. Regardless of the etching protocols and adhesive systems used, less microleakage was observed on the occlusal surface than on the gingival surface. Phosphoric acid etching provides better results than laser etching for enamel surface treatment on both occlusal and gingival surfaces. [ABSTRACT FROM AUTHOR]

Tooth wear or non-carious tooth surface loss is commonly seen in daily dental practices. This is particularly eminent with the increase of dental care awareness in an aging population who retain more of their dentition into their golden years. With the paradigm shift to adhesive dentistry, composite resin build up has shown to be one of the most predictable and minimally invasive procedure in restoring the function and aesthetic of patient's dentition. The present article reviews various techniques of additive direct composite build up, aiming to provide dental practitioners with an overview of the clinical steps in managing tooth wear. [ABSTRACT FROM AUTHOR]

A growing antimicrobial crisis has increased demand for antimicrobial materials. It has become increasingly popular to convert polymeric macromolecules into polymeric carbon particles (PCP) in order to achieve highly biocompatible materials with unique properties as a result of the ability to synthesize nanomaterials of the right size and add value to existing stable polymers. This work presents the tuning of PCP for antibacterial application by combining a biocidal polymer with one‐pot solvothermal synthesis. PCP displayed broad‐spectrum antibacterial activity via various mechanisms, including inhibition of bacterial cell walls, ROS generation, and antibiotic resistance. Furthermore, these biocidal PCP were observed to show excitation‐independent near‐white light emission which on the other hand is generally possible due to mixed sizes, doping, and surface effects. As opposed to the parent biocidal polymer, PCP added ROS‐mediated bactericidal activity, increased cytocompatibility, and nanofibers with anti‐adhesive effects and potential of imaging bacterial cells. [ABSTRACT FROM AUTHOR]

Enhancing the durability of the adhesive--dentin interface is regarded as one of the main goals of contemporary adhesive dentistry. This study aimed to evaluate the effect of plasma pretreatment on MMP-2 inhibition and on the immediate and delayed shear bond strength of a universal adhesive used in 'etch-and-rinse' or 'self-etch' mode. Sixty-four decoronated human maxillary premolars were used for the bond strength test, while sixty-four dentin beams (1 mm thick, 2 mm wide, and 6 mm long) were used for the MMP-2 inhibition test. The specimens in each study were divided into four main groups (n=16): Group A: the universal adhesive (G-Premio bond) used in the 'etch-and-rinse' mode. Group B: as Group A but with plasma treatment prior to adhesive application. Group C: the universal adhesive used in 'self-etch' mode. Group D: as Group C but with plasma treatment prior to adhesive application. Each group was further subdivided into two subgroups (I and II) aged for 24 hours or 6 months, respectively. The universal adhesive was applied following the manufacturer's instructions. Nonthermal plasma was applied using a PiezoBrush® PZ3 Handheld Device. A universal composite was then applied in all of the groups. The shear bond strength test was carried out using a universal testing machine, while the MMP-2 concentration was measured using a special ELISA kit. Statistical Analysis: The data were analysed using one-way ANOVA, Tukey's HSD test, or an independent sample t test at a significance level of 0.05. The highest mean value of shear bond strength (SBS) was recorded for Group BII (30.12 ± 2.29 MPa), while the lowest mean value was recorded for Group CII (12.25 ± 0.88 MPa). Significant differences were found between each set of aged subgroups, except for C1/D1, CII/DII, CI/CII and DI/DII. For MMP-2, the highest mean value was recorded for Group AI (0.483 ng/ml), while the lowest mean value was recorded for Group BII (0.086 ng/ml). Significant differences were found between each set of aged subgroups, except for C1/CII. Plasma pretreatment of an etched dentin surface prior to universal adhesive application seems to be a promising protocol for increasing the longevity of bonded composite restorations, as it significantly increased the SBS after six months of ageing. [ABSTRACT FROM AUTHOR]

Purpose: This narrative review aimed to survey the clinical outcomes of laminate veneers (LVs), including their survival and success rates. Study selection: An electronic search of MEDLINE/PubMed, Web of Science, Cochrane Library, and Google Scholar from 2000 to April 2023 was conducted using the keywords "laminate" OR "veneer" OR "porcelain" OR "feldspathic" OR "lithium disilicate" OR "composite resin" OR "zirconia" OR "survival" OR "success." Case reports, case series, reviews, abstracts, in vitro studies, and observational studies were excluded. Five researchers independently evaluated the titles and abstracts of all identified studies. Results: A total of 55 studies were identified. None of the studies met the criteria for zirconia LVs. According to the studies in this review, LVs fabricated with feldspathic porcelain, leucite-reinforced glass ceramics (LRG), and lithium disilicate ceramics (LDS) exhibited satisfactory survival and success rates. Furthermore, hydrofluoric acid etching followed by silane priming of the surface of ceramic LVs is necessary for improved clinical outcomes. The extent of dentin exposure significantly decreases the success rate of ceramic LVs. An appropriate adhesive luting process is required to achieve the long-term success of ceramic LVs. Dentin exposure should be minimized or sealed during tooth preparation to achieve a reliable and durable bond between LVs and abutment teeth. Conclusions: Based on this narrative review of the literature, the use of silica-based ceramic feldspathic porcelain, LRG, and LDS is recommended for LVs. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the effect of the atmospheric pressure plasma treatment as a surface treatment method on the contact angle and shear bond strength (SBS) of zirconia ceramics and the failure mode between the self-adhesive resin luting agent and zirconia. The zirconia specimens were divided into eight groups based on the surface treatment method: alumina blasting, air plasma, argon plasma (AP), Katana cleaner, ozonated water, ozonated water+AP, Katana cleaner+AP, and tap water+AP. The contact angles, SBS, and fracture modes were tested. AP treatment significantly reduced the contact angle (p<0.0001). The combination of AP and other cleaning methods showed a higher bond strength and more mixed fractures. Our findings indicate that using atmospheric pressure plasma with argon gas, combined with other cleaning methods, results in a stronger bond than when using alumina blasting alone. [ABSTRACT FROM AUTHOR]

Multifunctional therapeutics have emerged as a solution to the constraints imposed by drugs with singular or insufficient therapeutic effects. The primary challenge is to integrate diverse pharmacophores within a single-molecule framework. To address this, we introduced DeepSA, a novel edit-based generative framework that utilizes deep simulated annealing for the modification of articaine, a well-known local anesthetic. DeepSA integrates deep neural networks into metaheuristics, effectively constraining molecular space during compound generation. This framework employs a sophisticated objective function that accounts for scaffold preservation, anti-inflammatory properties, and covalent constraints. Through a sequence of local editing to navigate the molecular space, DeepSA successfully identified AT-17 , a derivative exhibiting potent analgesic properties and significant anti-inflammatory activity in various animal models. Mechanistic insights into AT-17 revealed its dual mode of action: selective inhibition of Na V 1.7 and 1.8 channels, contributing to its prolonged local anesthetic effects, and suppression of inflammatory mediators via modulation of the NLRP3 inflammasome pathway. These findings not only highlight the efficacy of AT-17 as a multifunctional drug candidate but also highlight the potential of DeepSA in facilitating AI-enhanced drug discovery, particularly within stringent chemical constraints. DeepSA is a novel molecular generation framework that uses deep-simulated annealing for structural modifications. AT-17 , selected based on DeepSA, shows significant efficacy in relieving oral pain, providing long-acting local anesthesia and anti-inflammation. [Display omitted] [ABSTRACT FROM AUTHOR]

The dental adhesive market is constantly evolving to meet the demands of dentists and patients, but new products and upgrades should be rigorously evaluated before being used in clinical practice. This study investigated the physicomechanical properties and dentin bonding efficacy of a newly upgraded universal adhesive compared to its predecessor. Twenty-four molars were divided into four groups (n = 6/group) based on adhesive (new vs. predecessor) and application mode [self-etch (SE) vs. etch-and-rinse (ER)] for evaluating their dentin microtensile bond strength (μTBS), failure pattern, and bonding interface. Additional thirty-six molars' crowns were perpendicularly sectioned to obtain flat mid-coronal dentin discs. The opposing dentin surfaces of each disc received contrasting treatments (new/predecessor adhesive applied in SE/ER mode), resulting in six interventions. The bonded discs (n = 6/intervention) were used to assess the adhesives' survival probability employing a double-sided μTBS test. The other physicomechanical properties examined were adhesives' oxygen inhibition layer (OIL), viscosity, hardness, elastic modulus, degree of conversion (DC), and in-situ DC. Both adhesive versions showed similar μTBS (P > 0.05), failure pattern (P > 0.05), and survival probability (P > 0.008). ER mode promoted resin tag formation and exhibited a slender adhesive layer for both adhesives. The newer adhesive version showed a thinner adhesive layer in general with narrower OIL (P < 0.001), less viscosity (P < 0.001), higher hardness (P < 0.05), elastic modulus (P < 0.05), DC (P < 0.001), and in-situ DC (P < 0.001). While the newly updated adhesive had superior physicomechanical properties with more fluidity, its dentin bonding efficacy and survival probability were comparable to its predecessor. [ABSTRACT FROM AUTHOR]

Structural connections are one of the most important parts influencing the overall performance of a wooden structure. The way of design of these can lead both to increasing and decreasing internal stresses occurring in the load-carrying elements and total deformations of the structure. Typical mechanical joints in wooden structures are defined as plastic hinges or, at best, semi-rigid. The innovative hybrid proposed in the paper with adhesive added between elements can be much stiffer than a typical connection, which can lead to assuming rigid joint and significant reduction in stresses and deformations of a structure. The research comprised 30 specimens in three groups (10 per each group: reference - without adhesive, hybrid with one-component PUR - polyurethane adhesive and hybrid with one-component PVAc - polyvinyl acetate adhesive) tested on the MTS 809 testing machine up to failure. An innovative idea was to connect elements initially by applying an accurately predicted tightening torque value to bolts. This resulted in obtaining enough clamping pressure between elements for adhesive curing, with none other equipment. The load was applied in parallel-to-grain wood direction. The results showed that utilising hybrid connection caused, both for PUR and PVAc adhesive, a huge increase in stiffness. When comparing to the reference no-adhesive, bolted connection, this was 2365% stiffer (nearly 24 times). Load-carrying capacity was higher too, however, the increase was not that significant and was at the level of 14.4% and 27.1%, for PUR and PVAc adhesives, consecutively. Worth noting is that the hybrid connection could continue to work after adhesive failure with 60% higher stiffness than the reference one and its load-carrying capacity was only 10% lower than the reference. Hybrid connections of this type can potentially serve as structural joints because of the innovative concept of combining components. Steel plates can be covered with adhesive and then inserted between wooden parts. Next, the tightened bolts can work as clamps producing enough pressure for adhesive curing, enabling the joint to be assembled directly on the construction site. Despite the mentioned advantages, before providing the connections' design methods, the idea needs to be tested towards various effects influencing wooden structures. Incorporating numerical modelling can be extremely important too. [ABSTRACT FROM AUTHOR]

To evaluate and compare the effect of calcium hydroxide [Ca(OH)2] and 2-hydroxyisocaproic acid (HICA) on the microhardness of root dentine. Fifty-one matured maxillary central incisors with straight root and type I canal configuration were decoronated to a standardized length of 16 mm. The root canals were cleaned and shaped using rotary instruments up to size F5. The tooth samples were then randomly assigned into three groups (n = 17) based on the intracanal medicament placed. Group A: control group with no intracanal medicament, Group B: root canals placed with Ca(OH)2, and Group C: root canals placed with HICA. After 1 week, the intracanal medicaments placed within the root canals were removed and the canals were dried. Subsequently, the specimens were split longitudinally into two halves and subjected to the Vickers microhardness test with indentations made at the coronal, middle, and apical-third root regions. The data were analyzed using one-way ANOVA and Tukey's post hoc tests. The control group showed significantly highest microhardness value (P < 0.001), followed by HICA and finally, Ca(OH)2 at the coronal, middle, and apical-third root regions, respectively. Nonetheless, there were no statistically significant differences in microhardness values across different root regions within each group. HICA was found to have a significantly lesser reduction in root dentine microhardness which could be a potential alternative to Ca(OH)2. Nevertheless, future studies are warranted to verify the present outcomes in the clinical setting. [ABSTRACT FROM AUTHOR]

Glass fiber-reinforced polymer (GFRP) anchor bolts are a new type of high-performance nonmetallic anchor with significantly higher tensile strength, a lighter weight, better corrosion resistance, and a lower cost than steel bars. Therefore, exploring the durability and bonding performance of GFRP anchor systems is of great importance for the structural design of protective engineering, especially in coastal environments. However, insufficient research has been conducted on the durability of GFRP resin bolts in seawater conditions, with no universal standard on the pullout testing of GFRP bolts. To study the durability and bonding performance of GFRP resin bolts, durability experiments were conducted in this work using artificial seawater, and the pullout tests were conducted using a large-scale concrete platform with different compressive strengths (21.2, 40.8, and 61.3 MPa). The results of the durability experiments indicated that the strength variations of the GFRP rods and epoxy resin materials in artificial seawater environments were less than 5%. Subsequently, indoor pullout tests using steel tubes filled with epoxy resin were conducted, and the test results indicated a critical anchor length value. Pullout tests of the GFRP resin bolts embedded in large-scale concrete blocks were also conducted with different strengths. According to the test results, all GFRP resin bolts embedded in the three concrete blocks with different compressive strengths exhibited rod fracture failure. The failure mode was not controlled via the compressive strength of the concrete blocks due to the high bonding strength between the resin and the rod, as well as between the resin and the concrete. Therefore, this GFRP resin anchor system could fully utilize the tensile strength of GFRP rods. This research offers significant practical value in verifying the safety and reliability of GFRP resin bolts in corrosive marine service environments, and it contributes to the application and development of GFRP materials in the engineering field, serving as a valuable reference for the structural design and further study of GFRP bolts. [ABSTRACT FROM AUTHOR]

[Display omitted] Antifouling coatings play a crucial role in preventing the adhesion of marine organisms, bacteria, and blood, making them a primary strategy for combating biofouling in the marine industry. However, conventional antifouling coatings suffer from drawbacks such as high toxicity, limited abrasion resistance, and unstable polymer degradation rates, which can have adverse effects on the environment, economy, and human health. Thus, there is an urgent need for the development of sustainable and nontoxic antifouling coatings. This review first presents four major antifouling strategies: traditional coatings based on wettability, traditional coatings with protective structures, nontoxic coatings based on main chain degradable polymers, and nontoxic coatings combining main chain degradation with branch chain hydrolysis polymers. Second, the review provides a comprehensive overview of antifouling coatings with diverse functionalities, including antibacterial, anti-protein, anti-blood, anti-incrusting, adhesive, self-healing, and corrosion-resistant properties. Then, the application of antifouling coatings in marine environments and the medical field is thoroughly explored. Additionally, the review addresses the current challenges encountered by antifouling coatings. Finally, a forward-looking perspective is presented, envisioning future advancements in this field. By addressing these aspects, this review aims to stimulate further development and innovation in the realm of antifouling coatings. [ABSTRACT FROM AUTHOR]

Infants are exceptionally fragile and physically vulnerable. Continuous monitoring of their vital characteristics and physiological parameters is vital for assessing their exact health status. The progressive achievements of bioelectrical, biophysical, biochemical and hybrid soft monitoring technologies in infant are discussed. We offer insights into the remaining challenges and translational hurdles of soft electronics for clinical-grade infant monitoring from the benchtop to the bedside. [Display omitted] Infants are exceptionally fragile and physically vulnerable who need special healthcare. Continuous monitoring of vital information of infants is essential for understanding their health status. Whereas modern infant health monitoring is carried out with dedicated facilities in controlled hospital settings, they are associated with several issues such as potential iatrogenic injuries, barriers for skin-to-skin parental bonding, and even complications during basic clinical tasks. Recently, soft electronics have become an accessory and mobile infant monitoring platform with remarkable advantages over existing technologies. This review comprehensively summarizes the research advances on soft electronics for advanced infant monitoring. We first introduce the physiological characteristics from anatomy, diseases, and treatments of infants. In accordance with these characteristics, we discuss the progressive achievements of soft bioelectrical, biophysical, biochemical, and hybrid monitoring technologies for infants. In addition, we offer insights into the remaining challenges and future directions of a soft electronics based intelligent system for clinical-grade infant monitoring from sensor design, data processing, power supply, and digital interactions in the era of Internet of Things. Finally, we highlight the translational challenges to be considered in bringing soft electronics for infant monitoring from the benchtop to the bedside. [ABSTRACT FROM AUTHOR]

Background: The prevalence of Candida glabrata healthcare‐associated infections is on the rise worldwide and in Lebanon, Candida glabrata infections are difficult to treat as a result of their resistance to azole antifungals and their ability to form biofilms. Objectives: The first objective of this study was to quantify biofilm biomass in the most virulent C. glabrata isolates detected in a Lebanese hospital. In addition, other pathogenicity attributes were evaluated. The second objective was to identify the mechanisms of azole resistance in those isolates. Methods: A mouse model of disseminated systemic infection was developed to evaluate the degree of virulence of 41 azole‐resistant C. glabrata collected from a Lebanese hospital. The most virulent isolates were further evaluated alongside an isolate having attenuated virulence and a reference strain for comparative purposes. A DNA‐sequencing approach was adopted to detect single nucleotide polymorphisms (SNPs) leading to amino acid changes in proteins involved in azole resistance and biofilm formation. This genomic approach was supported by several phenotypic assays. Results: All chosen virulent isolates exhibited increased adhesion and biofilm biomass compared to the isolate having attenuated virulence. The amino acid substitutions D679E and I739N detected in the subtelomeric silencer Sir3 are potentially involved— in increased adhesion. In all isolates, amino acid substitutions were detected in the ATP‐binding cassette transporters Cdr1 and Pdh1 and their transcriptional regulator Pdr1. Conclusions: In summary, increased adhesion led to stable biofilm formation since mutated Sir3 could de‐repress adhesins, while decreased azole susceptibility could result from mutations in Cdr1, Pdh1 and Pdr1. [ABSTRACT FROM AUTHOR]

Bisphenol A glycidyl methacrylate (Bis-GMA) is of great importance for dental materials as the preferred monomer. However, the presence of bisphenol-A (BPA) core in Bis-GMA structure causes potential concerns since it is associated with endocrine diseases, developmental abnormalities, and cancer lesions. Therefore, it is desirable to develop an alternative replacement for Bis-GMA and explore the intrinsic relationship between monomer structure and resin properties. Here, the betulin maleic diester derivative (MABet) was synthesized by a facile esterification reaction using plant-derived betulin and maleic anhydride as raw materials. Its chemical structure was confirmed by 1H and 13C NMR spectra, FT-IR spectra, and HR-MS, respectively. The as-synthesized MABet was then used as polymerizable comonomer to partially or completely substitute Bis-GMA in a 50:50 Bis-GMA: TEGDMA resin (5B5T) to formulate dental restorative resins. These were then determined for the viscosity behavior, light transmittance, real-time degree of conversion, residual monomers, mechanical performance, cytotoxicity, and antibacterial activity against Streptococcus mutans (S. mutans) in detail. Among all experimental resins, increasing the MABet concentration to 50 wt% made the resultant 5MABet5T resin have a maximum in viscosity and appear dark yellowish after polymerization. In contrast, the 1MABet4B5T resin with 10 wt% MABet possessed comparable shear viscosity and polymerization conversion (46.6 ± 1.0% in 60 s), higher flexural and compressive strength (89.7 ± 7.8 MPa; 345.5 ± 14.4 MPa) to those of the 5B5T control (48.5 ± 0.6%; 65.7 ± 6.7 MPa; 223.8 ± 57.1 MPa). This optimal resin also had significantly lower S. mutans colony counts (0.35 ×108 CFU/mL) than 5B5T (7.6 ×108 CFU/mL) without affecting cytocompatibility. Introducing plant-derived polymerizable MABet monomer into dental restorative resins is an effective strategy for producing antibacterial dental materials with superior physicochemical property. [Display omitted] • Plant-derived betulin is used as the raw bio-based diols to synthesize MABet. • The MABet concentration in dental resins affected their physicochemical properties. • The 1MABet4B5T resin with 10 wt% MABet exhibited stronger antibacterial activity. [ABSTRACT FROM AUTHOR]

The current study aimed to evaluate the effects of different combinations of chemical and mechanical challenges on the failure load, failure mode and composition of the resulting fracture surfaces of resin-composite restorations. Three resin composites were used to fill dentin disks (2 mm inner diameter, 5 mm outer diameter, and 2 mm thick) made from bovine incisor roots. The model restorations, half of which were preconditioned with a low-pH buffer (48 h under pH 4.5), were subjected to diametral compression with either a monotonically increasing load (fast fracture) or a cyclic load with a continuously increasing amplitude (accelerated fatigue). The load or number of cycles to failure was noted. SEM was performed on the fracture surfaces to determine the proportions of dentin, adhesive, and resin composite. Both cyclic fatigue and acid preconditioning significantly reduced the failure load and increased the proportion of interfacial failure in almost all the cases, with cyclic fatigue having a more pronounced effect. Cyclic fatigue also increased the amount of adhesive/hybrid layer present on the fracture surfaces, but the effect of acid preconditioning on the composition of the fracture surfaces varied among the resin composites. The adhesive or hybrid layer was found to be the least resistant against the chemomechanical challenges among the components forming the model restoration. Increasing such resistance of the tooth-restoration interface, or its ability to combat the bacterial actions that lead to secondary caries following interfacial debonding, can enhance the longevity of resin-composite restorations. • Resin-composite restorations modeled using dentin-composite discs. • Oral cavity conditions mimicked using accelerated fatigue and chemical preconditioning. • SEM analysis showed adhesive/hybrid layer prominent on fracture surfaces. • Cyclic fatigue had greater impact than preconditioning on degradation at interface. • Findings correlated with long-term clinical resin-dentin bond degradation studies. [ABSTRACT FROM AUTHOR]

To determine whether water sorption and solubility of a recently introduced self-adhesive cement is comparable to two clinically tested resin composite cements after thermal aging, and if this is affected by the curing mode. Whether water sorption is correlated with color difference and biaxial flexural strength was also investigated. Water sorption and solubility of three resin composite cements {RelyX Universal (RUV), (Panavia V5 (PV5), Panavia SA plus (PSA)} were measured after thermal aging. Disk-shaped specimens were either light-cured or autopolymerized (n = 15 per group). Color difference ΔE 00 and biaxial flexural strength were also obtained. Sorption was highest for RUV (auto: 54.9 ± 9.0 µg/mm3, light: 49.7 ± 4.9 µg/mm3), followed by PSA (auto: 37.7 ± 1.4 µg/mm3, light: 34.5 ± 1.1 µg/mm3) and PV5 (auto: 21.7 ± 0.7 µg/mm3, light: 22.1 ± 0.4 µg/mm3). Light-curing reduced solubility values, particularly for RUV (from 60.7 ± 20.8 µg/mm3 to 6.4 ± 0.8 µg/mm3). Color differences of ΔE 00 > 1.8 (considered clinically not acceptable) were noted after aging for RUV and PSA. Sorption and ΔE 00 values after aging were correlated linearly (R2 = 0.970). Biaxial flexural strength values were highest for PV5 (light: 153.4 ± 15.9 MPa; auto: 133.2 ± 18.0 MPa) and lowest for RUV (light: 99.3 ± 12.8 MPa; auto: 35.1 ± 8.3 MPa). Light-curing has beneficial effects on sorption, color stability, and biaxial flexural strength of resin composite cements. Cements containing 2-hydroxymethacrylate such as RUV and PSA are more prone to water sorption and color changes. • Water sorption and solubility of three resin composite cements were evaluated. • Light-curing decreased water sorption and solubility and increased strength. • Water sorption was linearly correlated with color difference ΔE 00. • Water sorption was linearly correlated with strength depending on curing mode. [ABSTRACT FROM AUTHOR]

Background: This study investigated effects of rapid high-intensity light-curing (3 s) on increasing transdentinal temperature and cell viability. Methods: A total of 40 dentin discs (0.5 mm) obtained from human molars were prepared, included in artificial pulp chambers (4.5 × 5 mm), and subjected to four light-curing protocols (n = 5), with a Valo Grand light curing unit: (i) 10 s protocol with a moderate intensity of 1000 mW/cm2 (Valo-10 s); (ii) 3 s protocol with a high intensity of 3200 mW/cm2 (Valo-3 s); (iii) adhesive system + Filtek Bulk-Fill Flow bulk-fill composite resin in 10 s (FBF-10 s); (iv) adhesive system + Tetric PowerFlow bulk-fill composite resin in 3 s (TPF-3 s). Transdentinal temperature changes were recorded with a type K thermocouple. Cell viability was assessed using the MTT assay. Data were analyzed using one-way ANOVA and Tukey tests for comparison between experimental groups (p < 0.05). Results: The 3 s high-intensity light-curing protocol generated a higher temperature than the 10 s moderate-intensity standard (p < 0.001). The Valo-10 s and Valo-3 s groups demonstrated greater cell viability than the FBF-10s and TPF-3 s groups and statistical differences were observed between the Valo-3 s and FBF-10 s groups (p = 0.023) and Valo-3 s and TPF-3 s (p = 0.025), with a potential cytotoxic effect for the FBF-10 s and TPF-3 s groups. Conclusions: The 3 s rapid high-intensity light-curing protocol of bulk-fill composite resins caused a temperature increase greater than 10 s and showed cell viability similar to and comparable to the standard protocol. [ABSTRACT FROM AUTHOR]

Introduction: The extensive use of nanoparticles underscores the importance of developing sustainable synthesis methods. There is a growing demand for green synthesis, which prioritises clean, safe, and environmentally friendly methods devoid of high temperature, pressure, energy consumption, and toxic chemicals. Aim: To produce copper sulfate nanoparticles through the utilisation of Citrus sinensis extract and assess their antibacterial efficacy against Streptococcus mutans, Staphylococcus aureus and Enterococcus faecalis. This addresses the requirement for innovative and environmentally friendly antimicrobial agents for dental purposes. Materials and Methods: This in-vitro study was conducted at the Department of Conservative Dentistry and Endodontics at Saveetha Dental College, located in Chennai, Tamil Nadu, India, during the timeframe of April 2023 to June 2023 following the acquisition of ethical clearance from the Scientific Review Board Committee. Utilising Citrus sinensis extract, a green synthesis method was employed to synthesise copper sulfate nanoparticles. Characterisation procedures included Fourier-transform Infrared Spectroscopy (FTIR) analysis, Scanning Electron Microscopy (SEM) imaging, Energy Dispersive X-ray Analysis (EDAX) analysis, and antibacterial testing. The antibacterial effectiveness of the nanoparticles was evaluated against Streptococcus mutans, Staphylococcus aureus and Enterococcus faecalis using the agar well diffusion method. The data were subjected to statistical analysis using Statistical Package for Social Sciences (SPSS) version 23.0 to assess antibacterial effectiveness. Analysis of Variance (ANOVA) was employed to analyse the Zone of Inhibition (ZOI) regarding antibacterial efficacy. Results: The copper sulfate nanoparticles, synthesised through a green approach, displayed a spherical morphology as affirmed by SEM and exhibited characteristic peaks in FTIR spectra. EDAX analysis confirmed the elemental composition of the nanoparticles. Notably, the nanoparticles showcased the most substantial antibacterial activity against Enterococcus faecalis followed by Staphylococcus aureus, and the least activity was seen against Streptococcus mutans. Conclusion: Copper sulfate nanoparticles synthesised through Citrus sinensis mediation show promising antibacterial efficacy against Enterococcus faecalis, highlighting their potential for dental applications. However, further investigations are necessary to assess their cytotoxicity, evaluate their clinical viability, and explore broader applications in antimicrobial contexts. [ABSTRACT FROM AUTHOR]

Cell deformation and changes in mechanical properties, such as adhesion, elasticity modulus, and height, are some of the most significant signs of cancer. This paper investigates the mechanical parameters of normal and cancerous cells in the breast and lungs. The lung's normal cell studied is MRC-5, and the cancerous ones include A-549, COR-L105, and CALU-6. MCF-10A is the normal breast cell studied, and MDA-MB-468, MDA-MB-231, and ZR-75-1 are cancerous. The mechanical specifications and cellular topography were obtained using nanoindentation by the atomic force microscope (AFM). The elasticity modulus and adhesion amounts for at least 96 indents were computed by mathematical averaging for each cell line in two different modes. The results indicate that cancer decreases the cells' elasticity modulus by one-tenth in the lung and lower than one-third in breast cells. Cancer cells are up to several hundred times more adhesive than normal cells. In addition, a cancerous cell's height is greater than normal cells. This study's elastic modules are compared to the other references. Overall, the results are compatible. [ABSTRACT FROM AUTHOR]

Computer-aided design and computer-aided manufacturing (CAD/CAM) techniques are based on either subtractive (milling prefabricated blocks) or additive (3D printing) methods, and both are used for obtaining dentistry materials. Our in vitro study aimed to investigate the behavior of human gingival fibroblasts exposed to methacrylate (MA)-based CAD/CAM milled samples in comparison with that of MA-based 3D-printed samples to better elucidate the mechanisms of cell adaptability and survival. The proliferation of human gingival fibroblasts was measured after 2 and 24 h of incubation in the presence of these samples using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the membrane integrity was assessed through the lactate dehydrogenase release. The level of reactive oxygen species, expression of autophagy-related protein LC3B-I, and detection of GSH and caspase 3/7 were evaluated by fluorescence staining. The MMP-2 levels were measured using a Milliplex MAP kit. The incubation with MA-based 3D-printed samples significantly reduced the viability, by 16% and 28% from control after 2 and 24 h, respectively. There was a 25% and 55% decrease in the GSH level from control after 24 h of incubation with the CAD/CAM milled and 3D-printed samples, respectively. In addition, higher levels of LC3B-I and MMP-2 were obtained after 24 h of incubation with the MA-based 3D samples compared to the CAD/CAM milled ones. Therefore, our results outline that the MA-CAD/CAM milled samples displayed good biocompatibility during 24-h exposure, while MA-3D resins are proper for short-term utilization (less than 24 h). [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) have been identified as agents that disintegrate the collagen structures of dental hybrid layers, resulting in reduced restorative bond strength. Multiple MMP inhibitors (MMPIs) are known to counteract this degenerative mechanism, thereby preserving bond strength and promoting the longevity of resin-based restorations. Additionally, literature suggests that certain MMPI materials possess antimicrobial/anticariogenic properties, potentially reducing the risk of secondary caries development. Therefore, this review article aims to narrate on the integration of matrix metalloproteinase inhibitors into adhesive systems and their impact on bond strength. [ABSTRACT FROM AUTHOR]