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Zahra Jowkar,1 Zahra Fattah,1 Saeedreza Ghanbarian,2 Fereshteh Shafiei1 1Oral and Dental Disease Research Center, Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran; 2Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, IranCorrespondence: Fereshteh Shafiei Tel +98-71-36263193Fax +98-71-36280804Email shafief@sums.ac.irAim: This study was conducted to evaluate the effects of three nanoparticle solutions used as dentin pretreatments on the microshear bond strength (μSBS) of a conventional glass ionomer cement (GIC) to dentin.Materials and Methods: Ninety intact human molars were used after sectioning their occlusal surfaces to expose flat dentin surfaces. The specimens were randomly assigned to nine groups (n = 10). Group A was the control group (without using the cavity disinfectant). In groups B, C, D, and E, the prepared dentin surfaces were treated with 1 cc 2% chlorhexidine (CHX), 0.1% silver nanoparticle (SNP), 0.1% titanium dioxide nanoparticle (TNP), and 0.1% zinc oxide nanoparticle (ZNP) solutions for 1 minute, respectively, before applying the conditioner. CHX, SNPs, TNPs, and ZNPs were applied for 1 minute after applying the conditioner in groups F, G, H, and I, respectively. The specimens were restored with a conventional GIC and underwent μSBS testing after 24 hours. The data were analyzed using the one-way analysis of variance and Tukey’s test (p=0.05).Results: The applications of the nanoparticles (SNP, TNP, and ZNP) after the conditioner were associated with significantly greater μSBS values compared to that of the control group (p values < 0.05). Significantly higher μSBS values were observed when TNP or ZNP was applied after the conditioner compared to their applications before the conditioner (p values < 0.05). The highest μSBS values were observed when TNP was applied after the conditioner.Conclusion: Dentin pretreatment with the nanoparticles after applying the conditioner enhanced the bond strength of the GIC to dentin compared with the control group. The best results were obtained for the TNPs applied after the conditioner.Keywords: glass ionomer cement, microshear bond strength, nanoparticles

Zahra Jowkar,1 Seyed Ahmadreza Hamidi,2 Fereshteh Shafiei,1 Yasamin Ghahramani3 1Oral and Dental Disease Research Center, Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran; 2Department of Operative Dentistry, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran; 3Department of Endodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, IranCorrespondence: Fereshteh Shafiei Tel +98 71-36263193Email shafief@sums.ac.irAim: This study was conducted to evaluate the effect of three nanoparticle solutions used as final root canal irrigants on the fracture resistance of endodontically treated roots.Materials and Methods: Sixty intact single-rooted premolar teeth were used after removing the crowns below the cementum–enamel junction to standardize the length of the remaining roots to 13 mm. After instrumenting the roots using ProTaper Universal rotary instruments up to size F4, the roots were randomly divided into six groups (n=10) according to the final irrigating solutions: Group 1: normal saline; Group 2: 2% chlorhexidine (CHX); Group 3: 17% EDTA+2.5% NaOCl; Group 4: 17% EDTA+0.1% silver nanoparticle (SNP) solution; Group 5: 17% EDTA+0.1% titanium dioxide nanoparticle (TNP) solution; Group 6: 17% EDTA+0.1% zinc oxide nanoparticle (ZNP) solution. After filling the root canals with gutta-percha and AH Plus sealer, the fracture resistance (FR) values were measured. The data were subjected to the one-way analysis of variance and the Tamhane post hoc test (p=0.05).Results: EDTA + NaOCl had the lowest FR value, followed by normal saline and CHX (p values < 0.05). No significant difference was found between the FR of roots irrigated with CHX and normal saline (p > 0.05). The application of nanoparticles (SNP, TNP, and ZNP) was associated with a significantly greater FR than that of other irrigation solutions (p values < 0.05).Conclusion: The final irrigation of root canals with nanoparticles enhanced the fracture resistance of the endodontically treated roots. The lowest FR value was observed for NaOCl.Keywords: fracture resistance, nanoparticles, root canal irrigants

Statement of problem: Secondary dental caries is a common clinical finding in composite restoration. The development of a bactericidal dental adhesive provides a promising method to reduce the risk of secondary caries. Objectives: This study aimed to assess the antibacterial activity of silver (Ag) and titanium dioxide (TiO2) nanoparticles incorporated into an experimental dentin bonding agent formulation. Materials and Methods: Ag and TiO2 nanoparticles at 0.05, 0.1, 0.2, 0.5, and 1 wt% concentrations were incorporated into the adhesives. The suspensions were sonicated to ensure homogenous dispersion of nanoparticles in the adhesive system. Formulation was composed of acetone, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]propane (Bis-GMA), 1,6-bis-[2-methacryloyloxyethyl carbonyl amino]-2,4,4-trimethylhexane (UDMA), trimethylolpropane trimethacrylate (TMPTMA), 2-hydroxyethyl methacrylate (HEMA), and photoinitiator, with polyvinylpyrrolidone (PVP) as the stabilizer. We counted the colony-forming units (CFU%) of two cariogenic bacteria, Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus), that were exposed to the powdered light cured adhesive specimens. The effects of various concentrations of each nanoparticle were compared by one-way ANOVA, followed by the post hoc Bonferroni test. Results: All samples exhibited definite antibacterial activity (P

A novel double network (DN) hydrogel nanocomposite with good compressive strength has been prepared by using Carboxymethyl Cellulose-g-Acrylic acid-Iron Oxides Nanoparticles (CMC-g-AA-IONs) as the primary network and polyacrylamide as the secondary network. The structure of the synthesized DN hydrogel nanocomposite was investigated by Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), and mechanical strength measurement. The synthesized DN hydrogel showed high mechanical strength (σ of 0.238 MPa), despite the water content of 90%. Its biocompatibility effect on sensitive nerve cells was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) test. The results showed that the DN hydrogel nanocomposite has no cytotoxicity on these cells and did not cause any disturbance or inhibit their growth and proliferation. [ABSTRACT FROM AUTHOR]

Aim: To assess the effect of acid‐etching duration time on the compressive strength, microstructure and shear bond strength of All‐Bond Universal adhesive to MTA‐Angelus (AMTA), and Biodentine (BD). Methodology: Forty‐eight cylindrical specimens (4 mm in diameter, 6 mm in height) of AMTA in four groups and 48 specimens of BD in four groups (n = 12) were prepared and stored for 72 h. The control groups were unetched whilst the three experimental groups were acid‐etched for 5, 10 and 15 s, respectively, followed by compressive strength testing. The effect of the various acid‐etching times on surface micromorphology was evaluated under a scanning electron microscope. Similar groups were bonded using All‐Bond Universal and Aelite Flo and shear bond strength was tested. Data were analysed using two‐way ANOVA and Tukey tests. Results: 10‐s and 15‐s acid‐etching reduced the compressive strength of AMTA and BD (P < 0.001), while 5‐s etching did not (P ≤ 0.86). In all the groups, BD had greater compressive strength compared to AMTA. Contrary to BD, the three etched AMTA groups had significantly higher shear bond strength compared to the control group (P < 0.001), with no significant differences between them. The etched groups of AMTA had shear bond strengths comparable to all the BD groups. Scanning electron microscope observations indicated variable surface morphologies such as remnant crystals and cracking/eroding in all our groups of AMTA; though these differences were less prominent for BD. Conclusions: Shortening the acid‐etching time to 5 s resulted in a beneficial effect in terms of resin bonding for AMTA while preventing the detrimental effect of 10‐s and 15‐s etching on the compressive strength of AMTA and BD. However, the three etching times had no effect on resin–BD bond. [ABSTRACT FROM AUTHOR]

The morphologies of the copper deposits obtained by pulsating overpotential regime with prolonged pulse and pause durations from the solution of 0.15 M CuSO4 in 0.50 M H2SO4 at overpotentials lower, higher and belonging to the plateau of limiting diffusion current density were compared with those obtained by the same electrodeposition regime from solutions of 0.075 and 0.30 M CuSO4 in 0.50 M H2SO4 and 0.15 M CuSO4 in 0.25 and 1.00 M H2SO4 at overpotentials outside the plateau of limiting diffusion current density. These samples were characterized by scanning electron microscopic (SEM) analysis and the cathodic polarization characteristics from solutions compared. Increasing the Cu(II) concentration led to an increase in the limiting diffusion current density. Decreasing the H2SO4 concentration shifts both beginning and the end of the plateau of the limiting diffusion current density towards higher electrodeposition overpotentials. Also, electrodeposition in solutions of 0.15 M CuSO4 in 0.25 and 1.00 M H2SO4 led to the formation of morphological forms of copper deposits characteristic for electrodeposition of copper from higher CuSO4 or lower H2SO4 in solution at some higher overpotentials.

This study was undertaken to investigate whether using a protein cross-linker, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), improves bonding stability of fiber posts to root dentin using three resin cements. Sixty human maxillary central incisor roots were randomly divided into six groups after endodontic treatment, according to the cements used with and without EDC pretreatment. In the etch-and-rinse group, 0.3 M EDC aqueous solution was applied on acid-etched root dentin prior to Excite DSC/Variolink II for post cementation. In the self-etch and self-adhesive groups, EDC was used on EDTA-conditioned root space prior to application of ED Primer Il/Panavia F2.0 and Clearfil SA, respectively. After microslicing the root dentin, a push-out bond strength (BS) test was performed immediately or after one-year of water storage for each group. Data were analyzed using three-way analysis of variance and Tukey tests (α=0.05). A significant effect of cement type, time, EDC, and Time x Cement and Time x EDC interactions were observed (p≤0.001). EDC pretreatment did not affect immediate bonding of the three cements (p>0.05k Aging significantly reduced the BS in all the groups (p≤0.001), but EDC groups exhibited a higher BS compared with the respective control groups (p<0.001>. Despite the significant effect of aging on decreasing the BS of fiber post to radicular dentin, EDC could diminish this effect for the three tested cements. [ABSTRACT FROM AUTHOR]

Statement of Problem: The use of tooth bleaching agents has been very popular treatment in dentistry. The bleaching agents have an inherent potential to impair surface properties of existing composite resin restorations. Purpose: This study evaluated the effect of a combined bleaching regimen on the surface microhardness of a Silorane-based and a sealed methacrylate-based composite. Materials and Method: Forty-five specimens of methacrylate-based composite (Ice) and 18 specimens of Silorane composite (Filtek Silorane, 3M ESPE; USA) were prepared and randomly divided into 5 (1-5) and 2 (6-7) groups (n=9), respectively. After 8-week aging, groups 1 and 6 were remained with no treatment. In groups 2, 4 and 5, the specimens were covered by a surface sealant and light cured. In groups 3, 4, 5 and 7, the specimens were bleached with hydrogen peroxide 40% and then carbamide peroxide 20% for seven days. In group 5, after bleaching, the sealant was removed by polishing. Surface microhardness was measured and the data were analyzed using one-way ANOVA and Tukey tests (α=0.05). Results: The microhardness values of groups 2 to 4 were significantly lower than that of group 1 (p <0.05). There was no significant difference among groups 1, 5, 6 and 7 (p> 0.05). Conclusion: The combined bleaching regimen used in this study had a substantial negative effect on methacrylate and sealed methacrylate composites but not on Silorane composite. Polishing following the bleaching on the sealed composite yielded a hardness value similar to that of unsealed methacrylate composite (control). [ABSTRACT FROM AUTHOR]

Several fluorine-substituted hydroxyapatite ceramics with the general chemical formula Ca5(PO4)3(OH)1-xFx (0≤x≤1), where x=0.0 (hydroxyapatite; HA), x=0.41 (fluorhydroxyapatite; FHA1) and x=0.69 (fluorhydroxyapatite; FHA2) and x=0.98 (fluorapatite; FA), were synthesised via pH-cycling method. The powders were characterised by using scanning electron microscope, transmission electron microscopy (TEM), Fourier transform infra-red (FTIR), X-ray diffraction (XRD) and F-selective electrode. The TEM micrographs showed that the increasing of fluoride ion concentration will cause a reduction in the aspect ratio of the produced crystallites. The XRD analysis of the calcined powders showed that all of the synthesised powders were pure and their XRD patterns were similar together. Eventually, the FTIR results suggest that the fluorine has substituted instead of hydroxyl groups in the fluoridated hydroxyapatite samples. [ABSTRACT FROM AUTHOR]

This in vitro study evaluated the effect of an oxalate desensitizer (OX) on the marginal microleakage of resin composite restorations bonded by two three-step and two two-step etch and rinse adhesives. Class V cavities were prepared on the buccal surfaces of 126 extracted premolars at the cementoenamel junction and randomly divided into nine groups of 14 each. In the control groups (1-4), four adhesives were applied, respectively, including Adper Scotchbond Multi-Purpose (SBMP), Optibond FL (OBFL), One-Step Plus (OS) and Excite (EX). In the experimental groups (5-8), the same adhesives, in combination with OX (BisBlock), were applied. And, in one group, OX was applied without any adhesive, as the negative control group (9). All the groups were restored with a resin composite. After 24 hours of storage in distilled water and thermocycling, the samples were placed in 1% methylene blue dye solution. The dye penetration was evaluated using a stereomicroscope. The data were analyzed using non-parametric tests. The OX application, in combination with OBFL and EX, resulted in significantly increasing microleakage at the gingival margins (p<0.05), while it had no effect on OS and SBMP (p>0.05). At the occlusal margins, no significant difference in microleakage was observed after OX application for each of four adhesives (p>0.05). [ABSTRACT FROM AUTHOR]

This clinical study evaluated the clinical performance of cuspal coverage with combined composite-amalgam restorations in endodontically-treated maxillary premolars over a three-year period. Thirty-six maxillary premolars, each with a Class II cavity in 36 patients ranging in age between 28 and 52 years, were selected after endodontic treatment. After reduction of the buccal and palatal cusps, internal coverage and veneering of the reduced buccal cusp was performed with composite. The remaining cavity and reduced palatal cusp were restored with high-copper amalgam. The restorations were evaluated at baseline and in one-, two- and three-year recalls with USPHS criteria. Changes in characteristics of the restorations were analyzed with the Cochran Q-test at a significance level of p<0.05. Most of the restorations received an overall score of alpha, except two restorations, which showed a slight discrepancy at the composite-amalgam interface after one year (p>0.05). Four restorations exhibited slight discoloration of the composite veneering after three years (p<0.05). No restoration exhibited fracture after three years. It was concluded that combined composite-amalgam cusp coverage of endodontically-treated maxillary premolars showed acceptable clinical performance after three years. [ABSTRACT FROM AUTHOR]

The potential advantage of magnetic resonance imaging (MRI) has been limited by artifacts due to the presence of metallic materials. For quantitative evaluation of the magnitude of artifacts from dental casting alloys and implant aterials in MR imaging, 11 dental casting or implant materials were imaged by means of 1.5 T MRI apparatus with three different sequences. Mean and standard deviation of water signal intensity (SI) around the sample in the region of interest (1200 mm2) were determined, and the coefficient of variation was compared for evaluation of the homogeneity of the SI. A variety of artifacts with different magnitudes was observed. Only one of the samples, composed mainly of Pd, In, and Sb, showed no artifacts in all imaging sequences. We concluded that selection of specific dental casting alloys according to their elemental compositions could minimize the metal artifacts in MRI; however, titanium alloys currently pose a problem with respect to causing MRI artifacts. [ABSTRACT FROM AUTHOR]

Aims: To compare the effects of repeated use of two one-bottle adhesives with that of two all- in- one adhesives (with acetone solvent) on bond strength to dentin. Materials and Methods: A flat dentin surface was prepared on 120 bovine incisors using 600- grit abrasive pape. The teeth were randomly assigned into 12 equal groups. The four adhesive systems [Prime and Bond NT (P&B NT), One-Step Plus (OS), iBond (iB), and G-Bond (GB)] were used at baseline, after the lid of the container had been opened 30 times, and after it had been opened 60 times. Before each use of the adhesives, the lids of the containers were left open for 1 min. The resin composites were applied on the dentin in a cylindrical split mold. After thermocycling, shear bond strength test was performed with a universal testing machine at 1 mm/min. We used Kruskal-Wallis and Dunn tests for statistical analysis. Results: There was no statistically significant difference among bond strength (MPa) of the groups of P&B NT (31.9 ± 4.6, 31.8 ± 6.5, 26.1 ± 6.7) and OS (33.2 ± 5.1, 30.9 ± 7, 29.3 ± 5.9), respectively (P > 0.05). The mean of the bond strength of iB and GB after 60 times (15.3 ± 4.1 and 12.2 ± 3.9, respectively) was significantly lower than that of iB and GB at baseline (23.5 ± 4.8 and 22.2 ± 4.5, respectively) (P < 0.05). Conclusions: Repeated use (60 times) of the all-in-one adhesive led to a decline in the dentin bond strength. To avoid this problem it would be advisable to have containers with smaller amounts of adhesive or perhaps those with only a singe dose.

We derive an analytic expression for the height correlation function of a homogeneous, isotropic rough surface based on the inverse wave scattering method of Kirchhoff theory. The expression directly relates the height correlation function to diffuse scattered intensity along a linear path at fixed polar angle. We test the solution by measuring the angular distribution of light scattered from rough silicon surfaces and comparing extracted height correlation functions to those derived from atomic force microscopy (AFM). The results agree closely with AFM over a wider range of roughness parameters than previous formulations of the inverse scattering problem, while relying less on large-angle scatter data. Our expression thus provides an accurate analytical equation for the height correlation function of a wide range of surfaces based on measurements using a simple, fast experimental procedure. [ABSTRACT FROM AUTHOR]

Statement of Problem: Application of fluoride and fissure sealant has an important cariostatic effect. The impact of topical fluoride, especially APF (Acidulated Phospheted Fluoride) gel on the restorative materials has been studied. Purpose: To assess the effect of repeated application of APF (1.23%) on the surface roughness of two sealant materials. Methods and Material: In this experimental study, 135 specimens of two sealant materials were prepared, using Aluminum cylindrical molds in three groups of 45 including: unfilled resin sealant (Clinpro), glass ionomer sealant (Triages) and glass ionomer sealant with covering of GC varnish. Then, these three groups were divided into three sub groups of 15 as follows: Group 1, 4, 7 (control): No treatment. Group 2, 8, 5: Single application using APF Group 3, 6, 9: Four times application using APF The APF was applied on the experimental specimen every time for 4 minutes. Then, the samples were stored in the distilled water. Finally, the surface roughness of the sealants was measured using Profilometer. The statistical analysis was performed by Kruskal-Wallis and Dunn tests. Results: Resin sealant exhibited no surface roughness changes following fluoride gel application (single or four applications). APF produced a statistically significant increase in the surface roughness of glass ionomer with and without varnish on them. Repeated application of APF on the surface glass ionomer specimen significantly increased their surface roughness. Conclusion: The result of the present study revealed that APF gel application significantly increases the surface roughness of glass ionomer sealants, without any effect on the resin sealant. [ABSTRACT FROM AUTHOR]

Objectives: The cervical resorption following intracoronal bleaching necessitates the application of impermeable cervical barriers. This study aimed to evaluate the effect of two bleaching agents on the compressive strength (CS) and shear bond strength (SBS) of two self-adhesive resins, TheraCem and Vertise Flow, to composite resin restorative material. Materials and Methods: Two hundred sixteen specimens from TheraCem and Vertise Flow were prepared in special molds and treated in three groups: nonbleached (control); sodium perborate-hydrogen peroxide (SP-HP) (sodium perborate +3% hydrogen peroxide); and HP gel (35% hydrogen peroxide gel). The CS of 72 specimens in the three groups was tested using a universal testing machine. For SBS test, 144 specimens from TheraCem and Vertise Flow in the three groups were bonded to Z250 composite using Single Bond Universal adhesive in self-etch and etch-and-rinse modes. SBS was measured using universal testing machine. Data were analyzed using two-way ANOVA and Tukey tests for CS and three-way ANOVA and Tukey tests for SBS. Results: Vertise Flow showed higher CS than TheraCem ( p < 0.001), while none of the bleaching agents deteriorated its CS. HP gel significantly lowered the CS of TheraCem ( p = 0.001). Bleaching agents increased the SBS of Vertise Flow while the SBS of TheraCem was not significantly affected. For both resin barriers, SBS was higher in the etch-and-rinse mode ( p < 0.05), except in nonbleached Vertise Flow ( p = 0.091). Conclusions: HP gel deleteriously affected the CS of only TheraCem during nonvital bleaching. The etch-and-rinse mode was preferred in terms of SBS for resin barriers., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Fereshteh Shafiei et al.)

Aim: To investigate the effects of Epigallocatechin gallate (EGCG) and curcumin, as a final irrigant on the fracture resistance of irradiated root that obturated with an epoxy resin sealer., Methodology: Eighty mandibular premolars were randomly divided into non-irradiated (NIR) and irradiated (IR) groups. The teeth were irradiated at 2 Gy per fraction, 5 times a week for a total dose of 60 Gy over 6 weeks. All specimens were decoronated, remaining 13±1 mm root length. Two groups were subdivided into four groups (n = 10): 1) non-instrumented; the intact root served as control. The other roots were instrumented with a pro-taper NiTi rotary system. The final irrigation used was 17% EDTA, followed by three irrigation solution groups; 2) 2.5% NaOCl, 3) 0.02% EGCG, and 4) 0.1% curcumin. Root canals were filled with gutta-percha and AH plus. All specimens were embedded in self-curing acrylic resin and loaded vertically at 1 mm/min until fracture occurred. Also, sealer penetration was assessed by confocal laser scanning microscopy (CLSM). The data were evaluated statistically using two-way ANOVA and Tukey test (α = 0.05)., Results: In irradiated roots, fracture resistance of EGCG and curcumin groups did not differ from non-instrumented roots, but they were higher than the NaOCl group (P = 0.006). However, NaOCl, EGCG, and curcumin in irradiated roots had comparable strength that was higher than in the non-instrumented group (p<0.001). Difference between irradiated and non-irradiated roots was observed only for NaOCl and non-instrumented groups (P≤0.004). In irradiated roots, a higher sealer penetration was observed in EGCG and curcumin groups compared to NaOCl., Conclusion: EGCG and curcumin could be promising final irrigants to reverse the adverse effect of radiotherapy on the strength of irradiated roots obturated with AH Plus sealer., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Tavangar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Exosomes are one type of nanosized membrane vesicles with an endocytic origin. They are secreted by almost all cell types and play diverse functional roles. It is essential for research purposes to differentiate exosomes from microvesicles and isolate them from other components in a fluid sample or cell culture medium. Exosomes are important mediators in cell-cell communication. They deliver their cargos, such as mRNA transcripts, microRNA, lipids, cytosolic and membrane proteins and enzymes, to target cells with or without physical connections between cells. They are highly heterogeneous in size, and their biological functions can vary depending on the cell type, their ability to interact with recipient cells and transport their contents, and the environment in which they are produced. This review summarized the recent progress in exosome isolation and characterization techniques. Moreover, we review the therapeutic approaches, biological functions of exosomes in disease progression, tumour metastasis regulation, immune regulation and some ongoing clinical trials., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Objective: Sodium hypochlorite solution (NaOCl) is an effective canal irrigant but interferes with the mechanical features of dentin and the bonding capability of adhesives when restoring endodontically treated teeth. This study evaluated whether access cavity resin sealing before using canal irrigant would augment the resistance of endodontically treated anterior teeth against fracture., Methods: Sixty maxillary incisors underwent endodontic treatment in five groups (n = 12). Irrigation with 5.25% NaOCl and 17% ethylenediaminetetraacetic acid (EDTA) was performed in all groups except for Group 5. After root canal obturation, in Group 1, the access cavity was kept unrestored. In Group 2, immediate restoration after obturation was achieved. For Group 3, delayed restoration after 1 week was provided. In Group 4 (pre-sealed), before canal irrigation, the dentin surface of access cavities was sealed using self-adhesive composite resin (Vertise Flow) and then restored after obturation. In Group 5, which was saline irrigated, immediate restoration was performed. After storage and thermal cycling for 5000 cycles at 5°C-55°C with a dwell time of 15 s and a transfer time of 5 s, teeth were statically loaded by a universal testing machine until a fracture occurred. Data were collected as the fracture resistance (FR) and analyzed using the one-way analysis of variance and Tukey's tests., Results: FR significantly differed between all groups (p < 0.001). The lowest FR was recorded in the unrestored group (284 ± 86 N), which was not statistically different from the immediately restored group (p = 0.065). The pre-sealed group exhibited the highest FR value (810 ± 127 N, p ≤ 0.02 vs. other groups). The FR of the saline-irrigated and delayed restored groups was almost similar (p = 0.13)., Conclusions: NaOCl/EDTA irrigation resulted in an adverse effect on FR. Delayed restoration could reduce this adverse effect. Access cavity pre-sealing with flowable composites led to a higher FR than conventional methods and may be considered an effective step during treatment procedures., (© 2024 The Author(s). Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Background: The main disadvantage of silver diamine fluoride (SDF) is its persistent dark coloring. The aim of this study was to cover this discoloration on affected primary tooth dentin with different materials and subsequently measure their shear bond strength (SBS)., Materials and Methods: In this in vitro study total of 60 primary teeth were demineralized and randomly divided into five groups ( n = 12). The tooth surfaces were treated with 38% SDF, and restorative cylinders were built on the dentin as follows: (1) phosphoric acid etching + GLUMA Universal Adhesive (GUA; etch-and-rinse mode) + composite resin (CR); (2) GUA (self-etch mode) + CR; (3) resin-modified glass ionomer (RMGI; Fuji II); (4) Surefil One (self-adhesive CR); and (5) TheraCem (self-adhesive resin cement) + CR. After restoration, the specimens were tested for SBS. Failure mode was determined by digital analysis and scanning electron microscopy. Data were analyzed by one-way analysis of variance and Tukey's honest significant difference post hoc test. P <0.05 indicated statistical significance., Results: Group 1 had significantly higher mean SBS ( P < 0.05) compared to Groups 2-5, while Group 5 had the least SBS ( P < 0.001). Mean SBS differences between Groups 2 and 3 were not significant ( P = 0.328). Group 4 had lower mean SBS than Groups 1 ( P < 0.001) and 2 ( P = 0.17). Most groups showed adhesive failure., Conclusion: CR associated with the universal adhesive in etch-and-rinse mode had much higher SBS than the other groups; therefore, we recommend it to cover the dark discoloration generated by SDF., Competing Interests: The authors of this manuscript declare that they have no conflicts of interest, real or perceived, financial or non-financial in this article., (Copyright: © 2024 Dental Research Journal.)

This study evaluated the fracture resistance of endodontically treated maxillary premolars restored with a new self-adhesive composite hybrid material (Surefil one [SO]) using different protocols. A total of 72 maxillary premolars were divided into 6 groups (n = 12). The control group included intact teeth, and the other 5 groups included teeth in which disto-occlusal cavities were prepared and endodontic treatment was performed. The prepared cavities were assigned to groups that were based on the restorative procedures: bulk-fill group, universal adhesive plus conventional bulk-fill composite resin plus a layer of conventional composite resin; SO-SC group, self-cured SO; SO-LC group, light-cured SO; SO-UA group, universal adhesive plus SO; or SO-core group, a 4.0-mm layer of SO covered by a layer of conventional composite resin. Specimens in each group underwent thermocycling and load cycling to test the fracture strength and fracture mode. The results were analyzed using analysis of variance and the Tukey test (α = 0.05). The SO-core group showed the highest mean (SD) fracture resistance, 959.9 (171.8) N, among the restored groups. The SO-core group did not differ significantly from the control group (P > 0.05) but did show significantly higher strength than all other test groups (P < 0.05) except SO-SC (P = 0.364). No significant differences were found between the bulk-fill, SO-SC, SO-LC, and SO-UA groups (P > 0.05). The SO-core group showed the highest number of unrestorable fractures, while the main fracture mode for the other groups was restorable fracture. Although the use of SO as a core material restored the fracture strength of endodontically treated premolars to the level of intact teeth, it also resulted in a higher incidence of unrestorable fractures. The SO-SC group demonstrated a high fracture resistance comparable to that of the SO-core group and had a greater tendency to experience restorable fractures., Competing Interests: No conflicts of interest reported.

Arbuscular mycorrhizal fungi (AMF) are one of the environment-friendly organisms that enhance plant performance. AMF affect the herbivorous insect community by indirectly modifying host plant nutrient uptake, growth, and defense, also known as priming. In the current study, under greenhouse conditions, the effects of inoculating tomato seedlings with four species of AMF, i.e., Funneliformis mosseae, Rhizophagus intraradices, Rhizophagus irregularis, and Glomus iranicus, were studied in relation to tomato plant growth parameters, plant defense enzymes, and total phenol content, and additionally, the life table of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) feeding on these plants was determined. The results demonstrated that the growth parameters of tomato plants, including plant height, stem diameter, number of leaves, root volume, leaf surface area, weight of the root, and aerial organs (containing the leaves and stem), were greater and larger in the AMF-inoculated plants compared to the non-inoculated plants. Furthermore, there were higher defense enzyme activities, including peroxidase, phenylalanine ammonia lyase and polyphenol oxidase, and also higher total phenol contents in the AMF-inoculated plants. The whitefly life table characteristics were decreased in the group feeding on the AMF-inoculated plants. All together, the AMF colonization made the tomato plants more resistant against B. tabaci by improving plant growth and increasing defense enzymes. The degree of priming observed here suggests the potential of AMF to have expansive applications, including their implementation in sustainable agriculture., (© 2024. Sociedade Entomológica do Brasil.)

Studies have provided evidence for the effectiveness of intensive short-term dynamic psychotherapy (ISTDP) in treating medically unexplained symptoms (MUS). This study aimed to examine the effectiveness of ISTDP on individuals living with irritable bowel syndrome (IBS) in terms of, emotion regulation (ER) abilities, defense mechanisms, quality of life (QOL), and IBS symptoms. A total of 30 patients diagnosed with IBS were recruited and randomly assigned to either the intervention ( n  = 15) or control ( n  = 15) group. Pre- and post-treatment assessments were conducted, along with a follow-up assessment after ten weeks. Repeated measures analyses of variance were employed to analyze the data. The findings revealed that ISTDP led to significant improvements in ER, defense mechanisms, and QOL, as well as a reduction in the severity and frequency of IBS symptoms. These results provide further support for the efficacy of ISTDP as a treatment modality for individuals with IBS., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Shafiei, Dehghani, Lavasani, Manouchehri and Mokhtare.)

Objectives: This study aimed to synthesize and characterize mesoporous zinc oxide nanoparticles (ZnO NPs) and also to evaluate the cytotoxicity of mesoporous ZnO NPs on L929 mouse fibroblast cell lines using 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay., Materials and Methods: The synthesized mesoporous ZnO NPs were extensively characterized using X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) analysis, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectra (EDAX), Fourier-transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). The cytotoxicity of mesoporous ZnO NPs was assessed by MTT assay. The study groups for cytotoxicity assay were normal saline, 0.1% calcined mesoporous ZnO NP solution, 1% calcined mesoporous ZnO NP solution, 0.1% noncalcined mesoporous ZnO NP solution, 1% noncalcined mesoporous ZnO NP solution, 0.1% ZnO NP solution, 1% ZnO NP solution, 2% chlorhexidine, and phosphate-buffered saline (PBS). The percentages of mean ± standard deviation of viable cells were analyzed., Results: Characterization of mesoporous ZnO NPs revealed that all the particles were in a more or less spherical shape with a wide particle size distribution of 70-100 nm. TEM image showed the uniformed and aggregated ZnO NPs with a typical size of 10-15 nm. BET analysis showed a mesoporous structure for the prepared mesoporous ZnO NPs. According to the MTT assay, chlorhexidine had the lowest cell viability percentage. Cell viability percentages of 0.1% mesoporous ZnO NP solutions (calcined and noncalcined) were statistically, significantly higher than 0.1% ZnO NP solution (p < .05). Cell viability percentages of 0.1% calcined and noncalcined mesoporous ZnO NP solutions and 0.1% ZnO NP solution were statistically, significantly higher than the 1% solutions (p < .05)., Conclusion: Mesoporous ZnO NPs exhibited less cytotoxicity against L929 mouse fibroblast cell lines compared to CHX and ZnO NPs, hence are safe to use., (© 2024 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Introduction: Overweight and obesity are common problems among teenagers regardless of ethnicity, race, and socio-economic status. Therefore, this study aims to explore the social and environmental factors impacting adolescents motivation for weight control in Gilan province, Iran., Methodology: Following a qualitative design, a content analysis approach was used to analyze the data. A total of 79 interviews were conducted with Adolescents (n = 23), Friends and Peers (n = 15), Parents (n = 12), Managers (n = 16), and Health care providers (n = 13), regarding adolescents obesity during 2019. MAXQDA V.10 software was used for our analysis., Findings: The main categories of environmental and social factors affecting adolescents motivation for weight control were external factors (the relative success of weight control intervention programs, the lack of environmental and social support, and the lack of family support for teenagers) that each one had some subcategories, and internal factors (competence, relatedness, and autonomy)., Conclusion: This study demonstrated the necessity of identifying environmental and social factors that are effective in reducing adolescents' motivation for weight loss. These factors are so influential that teenagers can't overcome them without receiving support from their environment and the government health-related policies. So, it seems that we need integrated multisectoral approaches and we suggest that health policymakers develop practical policies to control adolescents obesity by focusing on factors that have been mentioned in this study., (© 2024. The Author(s).)

Background: Worldwide, bladder cancer (BC) has been regarded as the tenth most common cancer with more than 573 000 new cases in 2020. This research presents a systematic review and meta-analysis of studies examining the quality of life (QOL) among patients with BC., Methods: The study was designed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 11 articles were extracted from a literature search conducted through electronic databases including PubMed, EMBASE, Scopus and Web of Science from the onset of January 2000 to June 2022. A random-effects model was applied to estimate the pooled QOL in patients with BC., Results: We included 11 primary studies in the final meta-analysis. Based on random effect analysis, total score of QOL was 53.92 (95% CI: 47.84 to 60) representing a moderate level of QOL among patients. Based on the analysis, it was found that physical items with a score of 49.82 (95% CI: 45.8 to 53.84) had a lower score in comparison with mental items at a score of 52 (95% CI: 49.54 to 54.47). In addition, the item of role limitations due to physical health with a score of 46.26 (95% CI: 20.11 to 72.41), and social functioning with a score of 46.25 (95% CI: 18.85 to 73.66), respectively, had the lowest QOL in patients with BC., Conclusion: Generally, the QOL among patients with BC was in a moderate condition, which can be improved through determining the influencing factors on QOL as a crucial strategy to define future treatment procedures in an effective manner., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The shortage of skilled nurses is a major concern for health systems worldwide. This may be partly due to the hesitancy of some nurses to enter or remain in the nursing career. This shortage consequently reduces the quality of standard patient care, increases patients' length of stay in a hospital, increases medical costs, and results in patients' dissatisfaction. This study aimed to explore hesitancy among senior undergraduate nursing students to pursue a career in nursing., Methods: This qualitative study adopted a thematic analysis approach. The population comprised senior undergraduate nursing students at Isfahan University of Medical Sciences, Iran, who indicated that they were hesitant to pursue a career in nursing. The study sampling was performed from May 2021 till February 2022 and continued until data saturation. Twenty-four interviews were conducted with the selected students. The attributes related to hesitancy among senior undergraduate nursing students to pursue a career in nursing were extracted as themes and sub-themes., Results: Four themes were identified: academic idiosyncrasies, individual characteristics, poor nursing market regulations (sub-themes: nursing as a tough and intense career, and unfavorable employment contracts), and the peculiarities of the workplace (sub-themes: conflict within work environment, and barriers to professional nursing practice)., Conclusions: The findings of this study showed that senior undergraduate nursing students weigh their future career options from various academic, personal, professional, and work environment dimensions. The findings provide new insights for decision makers to design and implement innovative strategies to promote retention in nursing careers. We recommend to provide academic counseling for all students and applicants of nursing before they enter the nursing education. Furthermore, we suggest to improve study and work environments, and to implement incentive programs to enhance enthusiasm of nursing students for pursuing a nursing career., (© 2024. The Author(s).)

On the basis of comments we received from readers, we made some changes in the original version of our article about our study and re-analyzed the data. In this corrected version, we found an inverse significant association between adherence to the Mediterranean diet and risk of depression in cohort studies (overall hazard ratio, 0.81; 95% confidence interval, 0.70-0.94). In addition, combining 8 cross-sectional studies that examined the association between adherence to the Mediterranean diet and depression, we found a significant inverse association (overall odds ratio, 0.81; 95% confidence interval, 0.71-0.92)., (© The Author(s) 2023. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

It has been shown that irradiation can cause structural changes in dentin that may reduce the bond strength of adhesives to dentin. Applying cross-linking or antioxidant agents may help reverse this detrimental effect and improve adhesion to dentin. This in vitro study aimed to evaluate the effects of epigallocatechin-3-gallate (EGCG) pretreatment and the time of adhesive bonding (24 hours vs 1 month) on the shear bond strength (SBS) of All-Bond Universal (ABU) to irradiated dentin using etch-and-rinse (ER) and self-etching (SE) modes. Flat dentin surfaces prepared from 96 extracted intact human molars were divided into 8 groups (n = 12) and bonded with ABU. In the control (CO) groups (CO/ER and CO/SE), bonding was performed on nonirradiated dentin; in the irradiated (IR) groups (IR/ER and IR/SE), bonding was performed on irradiated dentin; in the irradiated pretreated groups (IR/EGCG/ER and IR/EGCG/SE), irradiated dentin received a 0.1% EGCG pretreatment before bonding; and in the irradiated delayed bonding (DL) groups (IR/DL/ER and IR/DL/SE), bonding on irradiated dentin was performed 1 month after completion of radiotherapy. The irradiation protocol consisted of a total dose of 60 Gy with 2-Gy exposure applied 5 days per week for a period of 6 weeks. After bonding procedures were completed, the specimens were stored in 100% humidity at 37°C for 24 hours and then the SBS was tested in a universal testing machine. Data were analyzed using 1-way analysis of variance and Tukey tests. There was a statistically significant difference among the 8 groups (P < 0.001). Irradiation diminished the SBS in the IR/ER and IR/SE groups compared with their controls (P < 0.001). Pretreatment with EGCG significantly increased the SBS in the IR/EGCG/ER group only (P < 0.001). The difference between the IR/ER and IR/DL/ER groups was not statistically significant, and the difference between the IR/SE and IR/DL/SE groups was marginally significant (P = 0.056). Pretreatment with EGCG after acid etching restored the SBS of ABU to irradiated dentin, resulting in an adhesive performance equivalent to that observed with nonirradiated dentin. A 1-month delay between irradiation and bonding did not improve the SBS., Competing Interests: No conflicts of interest reported.

Objective: This study evaluated the effect of two natural antioxidants on the compromised bond strength of a resin-modified glass ionomer (RMGI) to the sodium hypochlorite (NaOCl)-affected pulp chamber dentin., Methods: Forty-two sound third molars were split into halves. The exposed pulp chamber dentin was ground to provide the flat dentin surfaces and divided into seven groups (n = 12), according to the solutions used for immersion: (1) Control, distilled water; (2) NaOCl, 5.25% NaOCl for 20 min; (3) NaOCl/Ethylenediaminetetraacetic acid (EDTA); 5.25% NaOCl for 20 min + 17% EDTA for 1 min; (4) NaOCl/TA, 5.25% NaOCl + 10% tanic acid (TA) for 5 min; (5) NaOCl/EDTA/TA, 5.25% NaOCl + 17% EDTA + 10% TA for 5 min; (6) NaOCl/PA, 5.25% NaOCl+ 10% proanthocyanidin for 5 min; and (7) NaOCl/EDTA/PA, 5.25% NaOCl+ 17% EDTA + 10% PA for 5 min. The RMGI was bonded on the treated dentin using a Tygon tube. After 24 h of storage, microshear bond strength (µSBS) was tested. Data in MPa were submitted to one-way analysis of variance and Tamhane test., Results: NaOCl significantly decreased the µSBS; NaOCl/EDTA and NaOCl/TA significantly increased the µSBS, higher than the control group (p < .05); and in the NaOCl/EDTA/TA group, the increased bond strength was at the level of the control group (p > .05). NaOCl/PA and NaOCl/EDTA/PA and NaOCl groups had comparable µSBS., Conclusion: TA could be suggested to provide effective bonding of RMGI and immediate sealing of the pulp chamber dentin after NaOCl irrigation., (© 2022 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Objective: Given the importance of preserving caries-affected dentin (CAD) in conservative dentistry, the shear bond strength (SBS) of different resin cements to CAD has been investigated. Here, we aimed to compare the SBS and remineralizing effect of a calcium silicate (TheraCem) and conventional self-adhesive cement (Panavia SA) on the SBS of CAD., Materials and Methods: Forty-eight extracted third molars (24 sound and 24 CAD) were used. In each group, 12 teeth were prepared for bonding to TheraCem or Panavia SA. After removal of the enamel and caries, resin composite cylinders were luted on the prepared dentin. After 28 days of storage in the artificial saliva, SBS was measured and the failure mode analysis was investigated. The images of fractured sections were analyzed using scanning electron microscopy and energy-dispersive X-ray to evaluate the Ca/P weight ratio., Results: SBS of CAD and sound dentin was not different when cemented with TheraCem (9.56 ± 4.51 vs. 9.17 ± 2.76, p = .806), but the CAD showed significantly lower SBS to Panavia SA (9.4 ± 2.36 vs. 7.39 ± 2.18, p = .015). The Ca/P ratio in CAD was significantly higher when bonded to both TheraCem and Panavia-SA than that of the controls (p = .001); however, this ratio was not different for those bonded to TheraCem compared to Panavia SA., Conclusions: Based on our results, TheraCem as a calcium silicate cement shows better SBS to attach the restoration to CAD as compared to Panavia SA. Obliteration and mineralization of the dentinal tubules in TheraCem were also higher than in Panavia SA. However, their ability to improve the amount of the Ca/P ratio in CAD was similar., (© 2022 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Understanding light-matter interaction at the nanoscale by observation of fine details of electromagnetic fields is achieved by bringing nanoscale probes into the nearfield of light sources, capturing information that is lost in the far field. Although metal coated probes are often used for nearfield microscopy, they strongly perturb the electromagnetic fields under study. Here, through experiment and simulation, we detail light collection by uncoated fiber probes, which minimize such perturbation. Second-harmonic light from intensely-irradiated sub-wavelength sub-surface features was imaged to avoid otherwise dominating fundamental light background, yielding clear nearfield details through a 50 nm aperture uncoated probe with ∼23 nm optical resolution. Simulations show how a metallic coating distorts optical nearfields and limits optical coupling into the probe in comparison to an uncoated probe., (Copyright © 2022. Published by Elsevier B.V.)

Purpose: To evaluate the influence of tannic acid and quercetin on the immediate microshear bond strength (μSBS) of two resin cements to dentin after internal bleaching., Materials and Methods: The access cavity in eighty extracted maxillary incisors was internally bleached except the control groups. The labial surfaces were ground to expose a flat dentin surface. The specimens were randomly divided into eight groups (n=10) as follows: 1) Control/Dou; Doulink without bleaching, 2) Bl/Dou; Bleaching+Doulink, 3) Bl+Ta/ Dou; Bleaching+Tannic acid+Doulink, 4) Bl+Qu/Dou;Bleaching+Quercetin+Doulink, 5) Control/ PSA; Panavia SA without bleaching, 6) Bl/PSA;Bleaching+Panavia SA, 7) Bl+Ta/ PSA; Bleaching+Tannic acid+Panavia SA, 8) Bl+Qu+PSA; Bleaching+Quercetin+Panavia SA. After 24 hours, the μSBS of the specimens was tested and the obtained data were analyzed with two-way ANOVA and Tamhane test (p⟨0.05)., Results: The µSBS of Doulink groups were higher than the PSA groups (p⟨0.001). The μSBS of Bl+Ta/Dou and Bl+Qu/ Dou groups did not differ from Bl/Dou (p⟩0.05). The μSBS of Bl+Ta/PSA group was statistically significantly higher than the Bl/PSA group (p⟨0.001). There was no significant difference between µSBS of Bl+Qu/PSA and Bl/PSA groups (p=0.39)., Conclusions: TA partially reversed the negative influence of internal bleaching on the µSBS of Panavia SA while quercetin did not increase the bond strength of both resin cements., (Copyright© 2022 Dennis Barber Ltd.)