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This study aimed to investigate the one-year bond strengths to dentin of one-bottle etch-and-rinse adhesive systems applied under different moisture conditions. Class V cavities were prepared in bovine incisors and randomly allocated (n = 8) according to the type of adhesive system used – SB (Adper™ Single Bond 2); PB (Prime & Bond 2.1); and XPB (XP Bond) – and the moisture condition kept in the cavity – moist, over-wet, and over-dry. Filtek™ Z250 was used for teeth restoration. Specimens for microtensile bond strength (µTBS) test were obtained and stored in water for 24 h or 1 year, and submitted to mechanical testing. Data were analyzed using t-tests, ANOVA and the Holm–Sidak post hoc test (α = 0.05). Weibull analysis was used to verify the reliability of specimens. The type of adhesive and the moisture condition of the substrate affected the µTBS. At 24 h, SB performed better under the moist and over-wet conditions. At 1 year, SB, PB, and XPB showed the greatest percentage reduction at the moist (∼38%), over-wet (100%), and over-dry (100%) conditions, respectively. The reliability of adhesives was affected by the variable factors tested. In conclusion, the solvent composition of adhesives and the moisture condition of the substrate play an important role in the bond strength and bonding stability of resin-based restorations, as well as on the reliability of the adhesive interfaces over time. [ABSTRACT FROM AUTHOR]

Objective. The aim of the present study was to characterize a novel resin-based monoblock endodontic obturation system consisting of a polymeric cone and a resin-based endodontic sealer. Methods. The preliminary tests performed for the experimental cone were as follows: cohesive strength, dimensional stability, standardization of the diameter and taper, calcium ion release, and radiopacity, for the characterization of the experimental sealer, film thickness and flow tests were performed. Tests were performed according to the American National Standards Institute/American Dental Association (ANSI/ADA) Standards Nos. 57 and 78. The experimental cone was compared to gutta-percha, whereas the experimental sealer was compared to AH Plus. Data were analyzed by Student's t-test (α = 0.05). Results. The experimental cone had superior values for cohesive strength and dimensional stability compared to gutta-percha. Regarding calcium ion release, the experimental system continued to release calcium ions after 30 days. Film thickness was similar for both endodontic sealers; conversely, the experimental resin-based sealer achieved higher values for flow compared to AH Plus. Conclusion. The experimental resin-based monoblock obturation system fully met the requirements of the ANSI/ADA Standard No. 78 and the ANSI/ADA Standard No. 57, except for radiopacity. Considering this, further studies are still needed to evaluate other radiopacifiers and the effect of their incorporation on the physicochemical properties of this novel resin-based monoblock endodontic obturation system. [ABSTRACT FROM AUTHOR]

Objectives: A systematic review was conducted to determine whether the etch-and-rinse or self-etching mode is the best protocol for dentin and enamel adhesion by universal adhesives. Data: This report followed the PRISMA Statement. A total of 10 articles were included in the meta-analysis. Sources: Two reviewers performed a literature search up to October 2014 in eight databases: PubMed, Web of Science, Scopus, BBO, SciELO, LILACS, IBECS and The Cochrane Library. Study selection: In vitro studies evaluating the bond strength of universal adhesives to dentin and/or enamel by the etch-and-rinse and self-etch strategies were eligible to be selected. Statistical analyses were conducted using RevMan 5.1 (The Cochrane Collaboration, Copenhagen, Denmark). A global comparison was performed with random-effects models at a significance level of p < 0.05. Results:The analysis of dentin micro-tensile bond strength showed no statistically significant difference between the etch-and-rinse and self-etch strategies for mild universal adhesives (p≥0.05). However, for the ultra-mild All-Bond Universal adhesive, the etch-and-rinse strategy was significantly different than the self-etch mode in terms of dentin micro-tensile bond strength, as well as in the global analysis of enamel micro-tensile and micro-shear bond strength (p≤0.05). Conclusions: The enamel bond strength of universal adhesives is improved with prior phosphoric acid etching. However, this effect was not evident for dentin with the use of mild universal adhesives with the etch-and-rinse strategy. Clinical significance: Selective enamel etching prior to the application of a mild universal adhesive is an advisable strategy for optimizing bonding. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of three experimental primers prepared with synthesized phosphorous and sulfur monomers (HEMA-P, ETMA and the mixture of HEMA-P/ETMA) on bonding to nickel–chromium (NiCr), silver–palladium (AgPd) and silver–gold (AgAu) metal alloys. The specimens were treated with experimental primers: HEMA-P, ETMA, HEMA-P/ETMA and Alloy Primer (Kuraray Noritake Dental Inc., Okayama, Japan) was used as commercial reference. Resin cement cylinders were built-up after application of tested primers on different alloy surfaces. Samples were stored in distilled water at 37 °C for 24 h before being subjected to shear bond tests using a mechanical testing machine. Shear bond strength (SBS) was recorded in MPa. Failure modes were classified under magnification as adhesive and mixed failure. Data were submitted to a two-way ANOVA and Student–Newman–Keuls׳ test. The statistically highest shear bond strength was observed with commercial primer to the AgPd alloy while the lowest value was shown with commercially available primers and experimental HEMA-P/ETMA to the NiCr alloy ( p <0.05). There was a predominance of adhesive failure, with the exception of commercially available primer, for which mixed failures were predominant. It could be concluded that formulations of metal primers containing HEMA-P or ETMA primers should be considered for use in the bonding protocol of NiCr alloys. [ABSTRACT FROM AUTHOR]

The global healthcare crisis with the COVID-19 pandemic has placed a significant overwhelming demand for intubation procedures and the need for reliable and accessible video laryngoscopes. The purpose of this scoping and technological review is to provide a comprehensive overview of the current state of the art, covering the period from 2007 to 2022, pertaining to the manufacturing process, characteristics, and validation of video laryngoscopes produced using additive manufacturing techniques. Following the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR), an exhaustive search was conducted across nine prominent databases (PubMed, Web of Science, Scopus, Cochrane, Prospero, Scielo, Embase, Lilacs, Virtual Health Libraries-VHL) and four patent databases (EPO/ESPACENET, WIPO/PATENTSCOPE, National Institute of Industrial Property (INPI), Google Patents). The main materials utilized for the impression, as well as the physical characteristics of the device are introduced at first. Crucial aspects to facilitate proper visualization of the anatomical structures during endotracheal intubation as the optimal angulation of the blade, the mechanical resistance of the device, traction force on the jaw, intubation time, and the experimental methods employed to validate its performance were reviewed in terms of their recent advances. [ABSTRACT FROM AUTHOR]

The radiological protection has the purpose of safeguarding the physical well-being of the user, preventing exposure to detrimental levels of ionizing radiation. This study introduces a novel, cost-effective category of lead-free elastomeric material designed for radiation shielding. The filler compounds utilized are notably lighter than conventional lead-based materials, enhancing user ergonomics during application. They comprise of a blend of barium sulfate combined or not with magnesium oxide with addition-cure liquid silicone rubber. To ensure the effectiveness of the radiation shielding, X-ray transmission measurements were performed for the different thicknesses of the materials and the results compared with Monte Carlo simulations. Additionally, the physical properties of the new materials, such as density, homogeneity, tensile strength, viscosity, and wettability, were also evaluated. The findings indicate that both materials fulfill the requirement for application in radiation protection garments. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the incorporation of halloysite nanotubes (HNTs) loaded with one of two calcium sources (i.e., calcium hydroxide/CaOH2 or beta-tricalcium phosphate/β-TCP) on the physicochemical and biological properties of an experimental resin-based dual-cured endodontic sealer. Materials and methods: HNTs were encapsulated with CaOH2 or β-TCP at 10 wt.%. HNTs containing CaOH2 or β-TCP were added into the experimental sealers at 50 wt.%. The control sealers were the calcium-free HNT-modified resin-based experimental sealer and AH Plus™, a commercially available endodontic sealer. Degree of conversion, setting time, flow, film thickness, radiopacity, dimensional stability, and calcium ions release were determined. Antibiofilm properties and cytocompatibility of the formulated sealers and commercial control were also evaluated. One and two-way ANOVA analysis followed by Tukey's post hoc test was conducted to evaluate the effect of the independent variable on the evaluated properties. Results: FTIR confirmed the encapsulation of calcium sources into HNTs. Regarding flow and film thickness, the values obtained from these sealers were in accordance with the specifications provided by ISO 6876. For radiopacity, AH Plus™ achieved the highest radiopacity (p<0.05). Among the experimental formulations, all experimental HNT-containing compositions exhibited values below 3 mm Al. The experimental sealers showed greater dimensional changes when compared to the commercial (AH Plus™) control. The release of calcium ions was observed for the HNT_CaOH2 and HNT_β-TCP sealers without statistical differences. Experimental sealers containing HNT_CaOH2 and HNT_β-TCP significantly reduced the CFU/mL count and showed cell compatibility. Conclusions: The findings of this study demonstrate that the incorporation of HNT_CaOH2 or HNT_β-TCP into resin-based experimental sealers promoted antimicrobial effects and gradual calcium release without impairing cytocompatibility or physicochemical properties of the sealers. Still, an adjustment to reach the minimal radiopacity established by ISO 6876 is needed. Clinical relevance: The experimental resin-based sealers seemed to be an alternative for endodontics. The incorporation of calcium sources exerts promising antimicrobial effects while displaying low cell toxicity. [ABSTRACT FROM AUTHOR]

Keywords: Nanocellulose; biological pretreatment; cellulase; eucalyptus; ; ; ; EN Nanocellulose biological pretreatment cellulase eucalyptus ZH 9363 9372 10 11/21/22 20221220 NES 221220 Introduction The global demand for cellulose nanofibers (CNF) and other cellulosic nanomaterials overcame 10,000 tons in 2018 and this demand is expected to increase to more than 70,000 tons by 2030 (Santmarti, Tammelin, and Lee [33]). In the present study, CNF were extracted from a bleached hardwood pulp using enzymatic hydrolysis as a pretreatment for subsequent mechanical fibrillation. In a comparison between unhydrolyzed pulps, that bleached pulp presented a higher crystallinity index than the unbleached one, which indicates that the bleaching sequence applied by our supplier partly removed some amorphous components, like hemicelluloses and lignin (De Campos et al. [10]). In general, compared to the unhydrolyzed CNF, it is clear that the CNF extracted from the unbleached pulp presented smaller decreases in diameter (around 75%) than those from bleached pulp, which showed decreases of almost 65%. [Extracted from the article]

Objectives Resin adhesives (RA) have been applied between resin composite (RC) increments, but there is no consensus on the impact of this technique on the properties of the final restoration. This study evaluated the effect of the presence of RA between RC layers on physical properties, translucency and long-term color stability of the restorative material. Methods Scotchbond™ Multi-Purpose (bond, 3M ESPE) and Adper™ Single Bond 2 (3M ESPE) were used as RA, and Filtek™ Z350 (3M ESPE) as RC. Specimens containing RA were prepared by applying 3 layers of the adhesive between 4 increments of RC; adhesive-free specimens were also used (control). Tests of water sorption and solubility, mechanical performance (microtensile cohesive strength, flexural strength, and flexural modulus, after immediate and long-term water storage), and translucency and color stability (after immediate and 1, 7, 90, and 180 days of water or wine storage) were performed. Scanning electron microscopy (SEM) images were also taken from the fractured specimens (flexural strength test). Data were analyzed using ANOVA and Tukey test ( p < 0.05). Results Scotchbond (SBMP) showed lower water sorption and solubility than the control ( p < 0.001), and an overall similar ( p ≥ 0.198, immediate tests) or higher ( p ≤ 0.019, long-term tests) mechanical performance. SBMP exhibited a rougher cross-sectional surface compared to the other groups. Translucency remained unaltered after 180 days of storage ( p ≥ 0.313), except for single bond that had increased translucency with wine storage ( p < 0.045). After 180 days, all groups changed color ( p ≤ 0.002), although more intensively when immersed in wine. Significance The presence of RA within RC increments increased the physical stability of the material, being this effect more evident by using the hydrophobic unfilled adhesive resin (SBMP). This study is the first to show positive results from the use of resin adhesives as modeler liquid of resin composite, which is common in clinical practice. [ABSTRACT FROM AUTHOR]

The sealing and bonding characteristics of luting cements may be affected by the application of desensitizers containing ingredients that induce chemical interaction with dentin organic matrix. This study evaluated the effect of different desensitizers on the immediate and long-term shear bond strength (SBS) of a self-adhesive resin cement (SARC) to dentin. Healthy bovine dentin specimens were used for the study. Gluma® Desensitizer, Desensibilize Nano P®, and Soothe® desensitizer were used in study groups, while the control group did not receive any treatment. Next, SARC (RelyXTM U200) in cylindrical mold was applied to the sample surface. All specimens were stored at 37 °C for 24 h or six months and tested for SBS. Additionally, water contact angle was measured using an optical tensiometer. Results were analyzed by analysis of variance and Student-t tests (p ˂ 0.05). Application of the different types of desensitizers had no significant influence on immediate or long-term SBS of SARC to dentin (p > 0.05). Differences for water contact angle were not statistically significant among the tested groups (p = 0.450). Within the limitations of the present study, it can be concluded that the application of the different types of desensitizers had no significant influence on the SBS of a SARC to dentin. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate and compare the effectiveness of two treatments for dentin hypersensitivity in vivo during 90 days of follow-up.Materials and Methods: The sample consisted of 117 teeth (13 patients) that were divided into three groups: control with carbomer 940 gel (n = 32) (placebo treatment), 2% sodium fluoride gel (n = 31) and low-level infrared diode laser (n = 54). Prior to the desensitizing treatment, the dentin hypersensitivity status of each tooth was assessed by an evaporative stimulus; the patient's response was evaluated using the Visual Analogue Scale (VAS) and by counting the Exposure Time to Air Blast (ETAB) with a dental air syringe. Re-evaluations of the treatments occurred after 5 min, 7, 15, 30 and 90 days. The statistical analysis was performed using the Kruskal-Wallis test, Friedman test, one-way ANOVA, Tukey's test and Spearman's rank correlation (α = 5%).Results: No significant differences were observed among the low-level laser, 2% topical fluoride and carbomer 940 gel applications. When the methods of evaluation (VAS and ETAB) were compared, there was no difference among the groups with respect to the values for every period of evaluation (p < 0.001), verifying that the scores obtained with the VAS decreased at the same proportion as the remaining time of ETAB increased.Conclusions: This study showed that both tested therapies were efficacious in controlling painful symptoms associated with dentin hypersensitivity over the entire 90-day follow-up period. The treatments were able to reduce the painful symptoms caused by dentin hypersensitivity, including placebo. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome originated by the new coronavirus (SARS-CoV-2) that emerged in late 2019, known to be a highly transmissible and pathogenic disease, has caused the COVID-19 global pandemic outbreak. Thus, diagnostic devices that help epidemiological public safety measures to reduce undetected cases and isolation of infected patients, in addition to significantly help to control the population's immune response to vaccine, are required. To address the negative issues of clinical research, we developed a Diagnostic on a Chip platform based on a disposable electrochemical biosensor containing laser-induced graphene and a protein (SARS-CoV-2 specific antigen) for the detection of SARS-CoV-2 antibodies. The biosensors were produced via direct laser writing using a CO2 infrared laser cutting machine on commercial polyimide sheets. The presence of specific antibodies reacting with the protein and the K3[Fe(CN)6] redox indicator produced characteristic and concentration-dependent electrochemical signals, with mean current values of 9.6757 and 8.1812 µA for reactive and non-reactive samples, respectively, proving the effectiveness of testing in clinical samples of serum from patients. Thus, the platform is being expanded to be measured in a portable microcontrolled potentiostat to be applied as a fast and reliable monitoring and mapping tool, aiming to assess the vaccinal immune response of the population. [ABSTRACT FROM AUTHOR]

We aimed to develop an alginate hydrogel (AH) modified with nano-/microfibers of titanium dioxide (nfTD) and hydroxyapatite (nfHY) and evaluated its biological and chemical properties. Nano-/microfibers of nfTD and nfHY were combined with AH, and its chemical properties were evaluated by FTIR spectroscopy, X-ray diffraction, energy dispersive X-Ray analysis, and the cytocompatibility by the WST-1 assay. The results demonstrate that the association of nfTD and nfHY nano-/microfibers to AH did not modified the chemical characteristics of the scaffold and that the association was not cytotoxic. In the first 3 h of culture with NIH/3T3 cells nfHY AH scaffolds showed a slight increase in cell viability when compared to AH alone or associated with nfTD. However, an increase in cell viability was observed in 24 h when nfTD was associated with AH scaffold. In conclusion our study demonstrates that the combination of nfHY and nfTD nano-/microfibers in AH scaffold maintains the chemical characteristics of alginate and that this association is cytocompatible. Additionally the combination of nfHY with AH favored cell viability in a short term, and the addition of nfTD increased cell viability in a long term. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of functionalizing a dental adhesive resin with YbF3/SiO2 fillers for use as radiopacifiers. Particles of YbF3/SiO2 were obtained with the high-energy mechanical milling method and characterized by both physical and chemical methods. After characterization, the particles were sieved and silanized prior to being incorporated into an adhesive resin. The stability of the particle suspension was then evaluated. After light activation, the radiopacity, degree of conversion, flexural strength and elastic modulus were determined. The dental adhesive resins with 10 and 15 wt% of filler provided satisfactory radiopacity, while flexural strength and elastic modulus were not affected. The degree of conversion was statistically lower than that of the control (p<0.05). The method used for incorporating the tested ytterbium fluoride/silicon dioxide particles at concentrations of 10 and 15 wt% was shown to be feasible for the development of a radiopaque dental adhesive system. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the whiteness index (WID) and surface roughness (Ra) of bovine enamel after simulated tooth brushing with different commercial and experimental whitening dentifrices. Materials and Methods: Cylindrical enamel bovine specimens were acid etched, stained, and divided in nine groups (n = 8): Colgate® Optic White®, Crest® Baking Soda and Peroxide, Arm and Hammer® Advanced White™ Extreme Whitening, Rembrandt® Deeply White® + Peroxide, Close up® White Attraction Natural Glow, Hinode Prowhite, and experimental dentifrice containing papain (PP), bromelain (PB), or papain and bromelain (PPB). Ra and WID were obtained initially and after 600, 1200, and 3,600 cycles of simulated tooth brushing. Data were analyzed using two‐way analysis of variance test (α = 0.05). Results: Ra was significantly influenced by both dentifrice (p = 0.043) and period of tooth‐brushing simulation (p < 0.001). Except for PP and PPB, all groups showed a statistically significant increase in Ra after simulated tooth brushing. After staining and brushing, none of the materials tested increased the initial WID. Conclusions: The effect of commercial whitening dentifrices may be related to their high abrasiveness. Experimental formulations tested provided a similar effect without undesired wear of enamel. Whitening dentifrices only act through an abrasive effect rather than bleaching the tooth structures. When used, special care must be taken for avoid undesired wear of enamel. Experimental dentifrices provided similar removal of extrinsic stains without undesired abrasiveness; however, this effect may be due to the use of less aggressive abrasives in their formulations. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Advancements in additive manufacturing for video laryngoscopes: a comprehensive scoping and technological review" published in the journal Systematic Reviews. The correction addresses a typographical error in the name of one of the authors, Dr. Neftali Lenin Villarreal Carreno, which was mistakenly published as "Neftali Lenin Villareal Carreno." The correction has been made to the original article. The authors of the article are Ana Cristina Beitia Kraemer Moraes, Chiara das Dores do Nascimento, Everton Granemann Souza, Mauricio Beitia Kraemer, Mauricio Moraes, Neftali Lenin Villarreal Carreno, Evandro Piva, and Rafael Guerra Lund. [Extracted from the article]

A new biofilm of cellulose coated with hydroxyapatite particles have been prepared using a simple, fast and low temperature process based on a microwave-assisted hydrothermal synthesis. The cellulose used as matrix of the biocomposite was extracted from banana stems residues. The hydroxyapatite coating was performed using calcium nitrate tetrahydrate, phosphoric acid, and 1,2-ethylenediamine dispersed in a cellulose/water solution, with posterior microwave-assisted hydrothermal synthesis, for 5 min at 140°C. The chemical, structural, thermal, and morphological properties of the composites were investigated by X-ray diffraction, infrared spectroscopy, thermogravimetry and field emission scanning electron microscopy. Results showed that the methodology was effective to produce high quality composites, with good thermal stability. Cell viability tests indicated that the cellulose/Hap films were not cytotoxic. [ABSTRACT FROM AUTHOR]

To evaluate the bleaching ability, the effect on enamel surface and cytotoxicity of novel tooth-whitening formulations containing papain, ficin, or bromelain. Forty bovine dental discs (6 cm ×4 cm) were pigmentated and randomly allocated into the following groups (n = 10): Group 1, 20 wt% carbamide peroxide (control); group 2, 1% papain-based whitening; group 3, 1% ficin-based whitening; and group 4, 1% bromelain-based whitening. The whitening gels were prepared and applied on the enamel three times per day once a week, for 4 weeks. Color measurement was obtained by CIEDE2000. Enamel Knoop microhardness and roughness were evaluated. The WST-1 assay was used to evaluate the cell viability of mouse fibroblast cells (L929). Data were statistically analyzed by one-way analysis of variance (ANOVA) and Student Newman Keuls's post hoc test at α = 0.05 significance level. Bromelain, ficin-based, and carbamide peroxide bleaching gels showed a similar color change (p < 0.001). Higher enamel hardness decrease and higher enamel roughness were caused by the carbamide peroxide (p < 0.05). The experimental whitening gels did not affect cell viability. Tooth bleaching gels containing bromelain, papain, or ficin have substantial clinical potential to be used in the development of peroxide-free tooth whitening gels. [ABSTRACT FROM AUTHOR]

• Photoinitiator system affected the biocompatibility of an adhesive resin. • Photoinitiation system is critical for development of new materials. • Improved biocompatibility was observed with the pair CQ + TBA. The aim of this study was to evaluate the effect of different photoinitiator systems on the cell viability and physico-chemical properties of an experimental adhesive resin of a two-step self-etch adhesive system. Eight photoinitiators and coinitiators were evaluated, camphorquinone (CQ); ethyl-dimethylamino benzoate (EDAB); diphenyliodonium hexafluorophosphate (DPIHFP); 1,3-benzodioxole (BDO); piperonyl alcohol (AP); 1,3-diethyl-2-thiobarbituric acid (TBA); bisphenyl phosphinic oxide (BAPO); and diphenyl phosphinic oxide (TPO). Seven experimental adhesive resins (Bis-GMA:TEGDMA – 1:1 by wt%) were formulated by varying the initiation systems: R CQ+EDAB (control), R CQ+EDAB+DPHFP , R CQ+BDO , R CQ+AP , R CQ+TBA , R BAPO and R TPO. The cell viability of the different photoinitiators in their isolated form and after being incorporated into the adhesive resins was evaluated using the MTT assay. The degree of conversion within the hybrid layer (DC in situ) was evaluated by micro-Raman spectroscopy; the polymerization kinetics, by FTIR spectroscopy. The water sorption (Wsp) and solubility (Wsl) were calculated by using percentage of gain and loss of mass. Data were analyzed using One-way ANOVA and Kruskal-Wallis tests (α = 0.05). When evaluated in their isolated form, the DPIHFP was considered cytotoxic in all concentrations evaluated. When incorporated into and adhesive resin, R CQ+TBA presented higher cell viability values than control and the highest values of DC in situ (p < 0.05). Additionally, the use of CQ + TBA showed a higher cell viability when compared with the conventional CQ + EDAB system. The pair CQ + TBA could be potentially useful in the development of materials with improved biocompatibility. [ABSTRACT FROM AUTHOR]

This work aimed to examine the effect of unreacted substances of four universal adhesives on cell viability, taking into account different sample preparation protocols. The protocols for sample preparation were as follows: P1: Disc-shaped specimens made of the adhesive material itself; P2: filter paper disc impregnated with the adhesive system; P3: bovine dentin disc impregnated with the adhesive system. The UHPLC/Q-TOF-MS spectroscopy was utilized to detect the type and quantity of unreacted substances released. The cell viability of the universal adhesives was evaluated considering the sample preparation protocol, as well as the different concentrations of each compound detected by the UHPLC/Q-TOF-MS spectroscopy in their isolated form. The WST-1 assay was employed to assess cell viability. From the extraction media, HEMA, BisGMA, CQ, EDAB, TPO, and UDMA were identified. When evaluated in P1, significantly higher amounts of CQ were detected in all of the universal adhesives (p<0.001). The sample preparation protocol was found to significantly influence cell viability (p<0.001). Notably, all universal adhesives exhibited a cytotoxic effect only when using the P1 protocol. Among the analyzed substances, CQ was identified as the most cytotoxic component (p<0.05). It was observed that disc-shaped specimens made with the material itself resulted in an overestimation of the cell viability outcomes for the universal adhesives. • Camphorquinone was shown to be the most cytotoxic component eluted. • Dimensions of the samples had a significant influence on the cell viability results. • Cell viability of dental materials should be performed in an as-used state. [ABSTRACT FROM AUTHOR]

• The adhesive systems lost their bonding ability with progressively storage time. • Apparently, HEMA-free adhesives produce materials with higher shelf-life stability. • Shelf-life simulation should be considered as routine for adhesive systems evaluation. To evaluate the micro-tensile bond strength to dentin (μTBS), the degree of conversion (DC) and nanoleakage expression (NL) of eight dental adhesives considering their expiry date (as-received, half-life and or end of shelf-life) after shelf-life simulation. Five universal adhesives (Single Bond Universal, SBU; Tetric Bond Universal, TBU; OneCoat Universal, OCU; OptiBond Universal, OBU; and Prime&Bond Elect, P&B), two two-step self-etch adhesives (Clearfil SE, CSE; and AdheSE, ASE) and one two-step etch-and-rinse adhesive (Adper Singlebond 2, ASB) were evaluated. Shelf-life was simulated by storing the materials in an acclimatization chamber for different periods of time. The μTBS was tested in accordance with ISO/TS 11,405. DC was evaluated by means of FTIR spectroscopy. NL was evaluated after ammoniacal silver challenge. The significance level of α = 0.05 was used for all statistical analyses. The μTBS to dentin of TBU, P&B, ASE, and ASB adhesive systems remained stable throughout the shelf-life periods evaluated, while for SBU, OCU, OBU, and CSE, decreased significantly after evaluation in the 'half-life' or 'end of shelf-life' condition (p < 0.05). Except for P&B, ASE and OBU, the degree of conversion significantly decreased after the shelf-life simulation (p < 0.05). OCU, ASE, and CSE showed significantly increased percentage of silver deposition within the adhesive layer (p < 0.05). Storing conditions and progressively longer storage time affect the performance of universal adhesives systems. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the efficacy of using rhBMP-2 (recombinant human morphogenetic protein-2) in the treatment of patients with cleft lip and palate defects (CLPD). Seven databases were screened: PubMed (Medline), Lilacs, Ibecs, Web of Science, BBO, Scopus, and The Cochrane Library. Clinical trials that evaluated the use of bioactive treatment with rhBMP-2 in the treatment of patients with CLPD were included. Statistical analyses were performed by comparing the standardized mean difference of bone formation volume and bone filling percentage (p = 0.05). Ten studies compared the use of rhBMP-2 and iliac crest bone graft (ICBG). The global analysis for bone formation volume and bone filling percentage showed that bioactive materials were similar to ICBG with a standardized mean difference of respectively 0.07 (95% CI - 0.41 to 0.56) and 0.24 (95% CI - 0.32 to 0.80). The available literature suggested that use of rhBMP-2 presented similar bone formation results to those of ICBG in secondary alveolar bone grafting for patients with CLPD. [ABSTRACT FROM AUTHOR]

Introduction. Mineral Trioxide Aggregate (MTA) is a tricalcium-based silicate, dicalcium silicate matrix. Despite its good biologic properties, some clinicians still claim to have difficulties in handling MTA after its preparation due to its sandy consistency. The aim of the present study was to evaluate the physicochemical properties and cytotoxicity of MTA Repair HP (Angelus, Londrina, PR, Brazil) compared with MTA Angelus (Angelus, Londrina, PR, Brazil). Materials and Method. The properties assessed were particle size, setting time, flow, film thickness, radiopacity, water solubility, compressive strength, and cytotoxicity. Statistical analysis was performed considering p < 0.05 as statistically significant. Results. For radiopacity, water absorption and solubility MTA Repair HP were statistically similar to MTA Angelus. The MTA Angelus had statistically different film thickness values, higher than MTA Repair HP (p < 0.05). Besides, MTA Angelus showed a lower and statistically different compressive strength after 28 days than MTA Repair HP (p<0.05). Additionally, MTA Repair HP set more slowly (p < 0.05). Relative to cell viability, MTA Repair HP was statistically similar to MTA Angelus after 24 and 48 h in cell viability. Conclusions. The MTA Repair HP presented similar cell viability, lower film thickness, higher flow, setting time, and compressive strength values after 28 days than MTA Angelus. In general, the MTA Repair HP presented physicochemical and biological properties similar to the MTA Angelus. [ABSTRACT FROM AUTHOR]

Abstract: Background: The use of bioactive proteins, such as rhBMP‐2, may improve bone regeneration in oral and maxillofacial surgery. Purpose: Analyze the effect of using bioactive proteins for bone regeneration in implant‐based rehabilitation. Materials and Methods: Seven databases were screened. Only clinical trials that evaluated the use of heterologous sources of bioactive proteins for bone formation prior to implant‐based rehabilitation were included. Statistical analyses were carried out using a random‐effects model by comparing the standardized mean difference between groups for bone formation, and risk ratio for implant survival (P ≤ .05). Results: Seventeen studies were included in the qualitative analysis, and 16 in the meta‐analysis. For sinus floor augmentation, bone grafts showed higher amounts of residual bone graft particles than bioactive treatments (P ≤ .05). While for alveolar ridge augmentation bioactive treatments showed a higher level of bone formation than control groups (P ≤ .05). At 3 years of follow‐up, no statistically significant differences were observed for implant survival (P > .05). Conclusions: Bioactive proteins may improve bone formation in alveolar ridge augmentation, and reduce residual bone grafts in sinus floor augmentation. Further studies are needed to evaluate the long‐term effect of using bioactive treatments for implant‐based rehabilitation. [ABSTRACT FROM AUTHOR]

This study evaluate the effect of nanoparticles (Bi 2 O 3 - bismuth oxide; YbF 3 - ytterbium trifluoride; SiO 2 - silicon dioxide) on radiopacity (R), translucency parameter (TP), degree of conversion (DC), bond strength to dentin (µTBS), and quality of the adhesive interface of experimental two-step, etch-and-rinse adhesive systems. The R was evaluated using an x-ray equipment. TP was verified in five replications and DC was performed in triplicate. The µTBS was evaluated in specimens stored in distilled water after 24 h, 6, 12 and 24 months. The bonded interfaces were qualitatively examined by scanning electron microscopy (SEM), and using x-ray energy dispersive spectroscopy (EDS) for elemental analysis. Data were statistically analyzed at α = 0.05. YbF 3 resulted in statistically greater R when compared with all the other groups ( p = 0.024), which did not differ from each other. Bi 2 O 3 was the adhesive with lowest TP. For DC, the YbF 3 and C showed similar results ( p = 0.627). Similar µTBS was obtained between groups. The addition of nanoparticles affected the chemical-mechanical properties. The incorporation of YbF 3 could be considered a promising approach for the development of radiopaque dental adhesives. [ABSTRACT FROM AUTHOR]

This study evaluated the biocompatibility and antibiofilm effects on Streptococcus mutans of an experimental self-etching adhesive system formulated with a natural vegetable product. The cytotoxicity of Clearfil Protect Bond (CPB), Clearfil SE Bond (CSEB), Adper SE Plus (AP), an experimental adhesive containing Butia capitata oil (EA) and an oil-free experimental adhesive as control (CA) was tested on 3T3/NIH mouse fibroblasts. Genotoxicity was indicated by micronuclei formation, and cell alterations were analyzed using light microscopy. To evaluate the effect of the adhesives on S. mutans biofilm, biomass samples were collected for dry weight and bacterial viability analyses, and the pH of the culture media was determined daily as an indicator of biofilm acidogenicity. The CA primer and EA uncured bond adhesive were the least toxic. No statistical difference was observed between EA and the untreated control, and EA showed similar effect to CPB. These findings suggest EA is biocompatible and presents activity against S. mutans biofilm. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the morphological bone response in animal experiments by applying hydroxyapatite grafts in critical and non-critical size bone defects. Current report followed the guidelines established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Animal experiments were selected by assessing repair of bone defects with hydroxyapatite as bone graft and with blood clot only as control. Eight articles were identified in specialized literature and included in the meta-analysis. Statistical analysis was carried out with a random-effect model (p = 0.05). Subgroup analyses were further performed to investigate bone repair in critical and non-critical bone defects. Comprehensive analysis of bone repair outcome showed a statistically significant difference between hydroxyapatite and blood clot control (p < 0.05). Subgroup analyses showed statistically significant difference for critical bone defects (p < 0.05). No statistically significant difference was reported in non-critical bone defects (p > 0.05). Although animal studies revealed a high risk of bias and results should be interpreted with caution, the literature suggests that non-critical bone defects may heal spontaneously and without the need of a bone graft. Conversely, when critical-size defects are present, the use of hydroxyapatite bone graft improves the bone repair process. [ABSTRACT FROM AUTHOR]

to evaluate the different bonding strategies for repairing aged resin composite restorations. The review was reported according to PRISMA Statement and registered in the Open Science Framework (DOI:10.17605/OSF.IO/WZTGS). Two reviewers performed a literature search across Embase (758), Pubmed (1244), Scopus (4300), The Cochrane library (128) and Web of Science (2538) databases. The risk of bias was assessed according to random sequence generation, blinding of outcome assessment, incomplete outcome data, selective reporting, coefficient of variation and other bias. Forty-four in vitro studies with different repair strategies on aged resin composite substrates were included from 1990 up to July 2022 which evaluated superficial treatment using shear, flexural, tensile, and bond strength tests. Most frequent treatments were diamond bur, air abrasion. Meta-analysis showed an overall effect significant to diamond bur (shear test; p = 0.02), air abrasion (shear; p = 0.009; flexural, p = 0.003; tensile; p = 0.004 tests), and to phosphoric acid (tensile test, p < 0.00001). Within the limitations of this study, strategies for improving bond to aged composites may consider better bond using air abrasion or diamond burs, and surface etching with phosphoric followed by application of adhesive system. • Surface treatment on composite resin that results in significant bonding. • Repair of composite resin restorations with aged substrate. • Improved surface treatments and bonding agents to repair aged resin. • Retentions in aiding adhesion between aged composite resin and a repair. [ABSTRACT FROM AUTHOR]

[Display omitted] • Antioxidants may act as polymerization inhibitors of resin formulations. • Incorporation of quercetin increased the yellowing index of the resin blend. • Incorporation of Gallic acid may reduce the mechanical strength of the resin. • Ascorbic acid did not function as a polymerization inhibitor. This study aimed to evaluate the physico-mechanical and biological properties of experimental adhesive resins modified with different antioxidants as radical polymerization inhibitors. The adhesive resins were formulated by mixing BIS-GMA, TEGDMA and HEMA (mass ratio of 50/25/25 wt%) and a tertiary initiation system (CQ + EDAB + DPHIHF – molar concentration of 1 %, 2 % and 1 %, respectively) together. Different antioxidants were added (1 mol%) to aliquots of the experimental resin, as follows: BHT (Butylated hydroxytoluene); HQ (hydroquinone); QC (quercetin); GA (gallic acid); and AA (ascorbic acid). An unmodified resin was used as control. The resin adhesives were tested with regard to sensitivity to ambient light, degree of conversion, cohesive strength, yellowing index, color stability; in addition, translucence and cytotoxicity (MTT assay) were analyzed. The data were analyzed using ANOVA and Tukey post-hoc tests (α = 5 %). The control and AA-based adhesive failed in the sensitivity to ambient light test. Adhesives modified with BHT and AA showed lower DC than the others. Color was considerably changed for the QC-containing adhesive. The presence of QC in the adhesive resulted in a higher yellowing index. When compared with the control, the addition of GA resulted in a reduction of the cohesive strength of the materials. All adhesives demonstrated similar cell viability and translucency. The use of alternative antioxidants as polymerization inhibitors rather than the synthetic types traditionally used showed potential application for the formulation of novel dental adhesive resins without significant impairment of the biological and physico-mechanical performance of the material. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to synthesize and characterize biodegradable polymer-based matrices loaded with CaO nanoparticles for osteomyelitis treatment and bone tissue engineering. Materials and methods: Poly(ε-caprolactone) (PCL) and PCL/gelatin (1:1, w/ w) solutions containing CaO nanoparticles were electrospun into fibrous matrices. Scanning (SEM) and transmission (TEM) electron microscopy, Fourier transformed infrared (FTIR), energy dispersive X-ray spectroscopy (EDS), contact angle (CA), tensile testing, and antibacterial activity (agar diffusion assay) against Staphylococcus aureus were performed. Osteoprecursor cell (MC3T3-E1) response (i.e., viability and alkaline phosphatase expression/ALP) and infiltration into the matrices were evaluated. Results: CaO nanoparticles were successfully incorporated into the fibers, with the median fiber diameter decreasing after CaO incorporation. The CA decreased with the addition of CaO, and the presence of gelatin made the matrix very hydrophilic (CA = 0°). Increasing CaO concentrations progressively reduced the mechanical properties ( p ≤ 0.030). CaO-loaded matrices did not display consistent antibacterial activity. MC3T3-E1 cell viability demonstrated the highest levels for CaO-loaded matrices containing gelatin after 7 days in culture. An increased ALP expression was consistently seen for PCL/CaO matrices when compared to PCL and gelatin-containing counterparts. Conclusions: Despite inconsistent antibacterial activity, CaO nanoparticles can be effectively loaded into PCL or PCL/gelatin fibers without negatively affecting the overall performance of the matrices. More importantly, CaO incorporation enhanced cell viability as well as differentiation capacity, as demonstrated by an increased ALP expression. Clinical significance: CaO-loaded electrospun matrices show potential for applications in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Objectives This study systematically review the literature to assess the effectiveness of antibacterial monomers incorporated into dental adhesive systems against major oral bacteria; as well as the research advances and the future prospects of this technology. Methods The following seven databases were screened: MedLine (PubMed), Lilacs, Ibecs, Web of Science, Scopus, Scielo , and The Cochrane Library . Furthermore, the online system Questel Orbit (Paris, France) was accessed to obtain patent data. The inclusion criteria were articles and patents that investigated the antimicrobial activity of antibacterial monomers in dental adhesive systems. Only documents written in English, Spanish or Portuguese were included. Results After screening, 33 studies and eight patents fulfiled all the criteria and were included. Antibacterial agents, such as QA, MDPB, DMAHM and DMADDM were found in patents, which claimed their incorporation into adhesive compositions, dental cements, composite resins. MDPB was the only antimicrobial monomer incorporated into a commercially available adhesive system, Clearfil Protect Bond™ (Kuraray Co. Ltd., Japan). All studies reported the inclusion of antimicrobial monomers in adhesive systems to be an effective dental treatment strategy. Significance There are potential areas to be explored with antibacterial monomers for dentistry, and their use could have important implications for future more conservative dental treatments. Although there is evidence of antibacterial activity from in vitro studies, clinical studies must be conducted to confirm the effectiveness of these materials in the prevention of dental pathologies. [ABSTRACT FROM AUTHOR]

This study investigated the effect of different monomeric systems and inorganic fillers on the physical properties of experimental resin adhesives and on the immediate and 6-month bond strength to dentin. Two, 2-step self-etch adhesive systems were prepared: two primers (constituted of GDMA-P, ethanol, water, and HEMA or PEG(400)-UDMA) and two adhesives (constituted of Bis-GMA, TEGDMA, and HEMA or PEG(400)-UDMA). Next, the adhesives were allocated into three groups according to filler incorporated: unfilled (control), silica (SiO 2 ), or ytterbium trifluoride (YbF 3 ). Degree of conversion (DC, after 30 and 60 s of light-activation), water sorption (WS) and solubility (SL), and flexural strength ( σ ) and modulus ( E f ) tests were performed for all adhesives. A microtensile bond strength (µTBS) test to dentin was evaluated after 24 h (immediate) and 6 months (6-month) of water storage using a universal testing machine (DL500, EMIC). Data were analyzed using statistical tests ( α =5%). The adhesives showed similar DC at a same light exposure time, although light-activation for 60 s improved conversion of monomers. The unfilled HEMA-containing adhesive showed higher WS, SL, σ and E f compared to others. The incorporation of fillers into the adhesives did not affect negatively the immediate µTBS results; however, after 6 months the presence of SiO 2 impaired in complete premature failures, and the presence of YbF 3 reduced the µTBS in the PEG(400)-UDMA-based group. The unfilled HEMA-containing group also reduced bond strength after 6 months of water storage. In conclusion, depending on the resin matrix composition, YbF 3 seems to be a good option for reinforcing adhesive systems. [ABSTRACT FROM AUTHOR]

Objectives This study reports on the synthesis, materials characterization, antimicrobial capacity, and cytocompatibility of novel ZnO-loaded membranes for guided tissue/bone regeneration (GTR/GBR). Methods Poly(ɛ-caprolactone) (PCL) and PCL/gelatin (PCL/GEL) were dissolved in hexafluoropropanol and loaded with ZnO at distinct concentrations: 0 (control), 5, 15, and 30 wt.%. Electrospinning was performed using optimized parameters and the fibers were characterized via scanning and transmission electron microscopies (SEM/TEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), contact angle (CA), mechanical testing, antimicrobial activity against periodontopathogens, and cytotoxicity test using human dental pulp stem cells (hDPSCs). Data were analyzed using ANOVA and Tukey ( α = 5%). Results ZnO nanoparticles were successfully incorporated into the overall submicron fibers, which showed fairly good morphology and microstructure. Upon ZnO nanoparticles’ incorporation, the PCL and PCL/GEL fibers became thicker and thinner, respectively. All GEL-containing membranes showed lower CA than the PCL-based membranes, which were highly hydrophobic. Overall, the mechanical properties of the membranes were reduced upon ZnO incorporation, except for PCL-based membranes containing ZnO at the 30 wt.% concentration. The presence of GEL enhanced the stretching ability of membranes under wet conditions. All ZnO-containing membranes displayed antibacterial activity against the bacteria tested, which was generally more pronounced with increased ZnO content. All membranes synthesized in this study demonstrated satisfactory cytocompatibility, although the presence of 30 wt.% ZnO led to decreased viability. Significance Collectively, this study suggests that PCL- and PCL/GEL-based membranes containing a low content of ZnO nanoparticles can potentially function as a biologically safe antimicrobial GTR/GBR membrane. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to synthesize an alternative acidic monomer (polypropylene glycol phosphate methacrylate - Poly-P) to constitute experimental two-step selfetch adhesive systems and also to evaluate its influence on the pH and microshear bond strength (µSBS) to enamel. Methods: Primers containing Poly-P (10, 15, 30 or 50 wt.%), HEMA, ethanol, and water were prepared and allocated in subgroups according to a buffered or non-buffered pH. One experimental control and one commercial (Clearfill™ SE Bond) references were used. mSBS protocol was performed at human enamel, followed by mechanical testing. Scanning electron microscopy (SEM) was performed after each primer application. Data was analysed by one-way Kruskal-Wallis and Student-Newman-Keuls tests (p < 0.05) and by linear regression predictive models. Results: As greater the Poly-P content, the lower the primer's pH. Buffered groups showed lower μSBS values than non-buffered groups. Groups with Poly-P content equal or higher than 30 wt.% showed similar mSBS results when compared to the controls. SEM images demonstrated that primers with high Poly-P content etched enamel with prisms exposure. Conclusions: The pH of the primer was directly influenced by the concentration of acidic monomer, which directly affected the adhesion to enamel. Both the acidity and the type of acid-functional monomer present in the adhesive influenced the bond strength results. Conclusions: The pH of the primer was directly influenced by the concentration of acidic monomer, which directly affected the adhesion to enamel. Both the acidity and the type of acid-functional monomer present in the adhesive influenced the bond strength results. Clinical significance: Poly-P synthesis was easy and effective, and considering the good bond strength results obtained, this acid-functional monomer may be potentially used in the formulation of self-etch dental adhesive systems. [ABSTRACT FROM AUTHOR]

In this study, we investigate seed oil from the fruit of Butia capitata , a native palm from South America, as feedstock for fatty acid methyl ester synthesis. Determination of the fatty acid profile, saponification index, acidity index, iodine index, viscosity index, flash point and levels of calcium, magnesium, sodium and potassium demonstrate that it is a suitable starting material for biofuel according to the requirements of Brazilian, American and European agencies and that it has the typical characteristics for use with fossil fuel and the possibility of application in diesel-based engines without drastic performance changes. [ABSTRACT FROM AUTHOR]

Objectives This study evaluated the performance of phenylbis (2,4,6-trimethylbenzoyl)-phosphine oxide (BAPO) as an alternative photoinitiator in the polymerization kinetics (PK), flexural strength (σ) and elastic modulus (E) of a model dental resin. Methods A monomer mixture based on Bis-GMA and TEGDMA was used as model dental resin. Initially a screening was performed to evaluate BAPO concentrations (0.125, 0.25, 0.50, 1, 2, and 4mol%). Photoinitiator systems were formed with the combination of camphorquinone (CQ), ethyl-dimethylamino benzoate (EDAB), diphenyliodonium hexafluorophosphate (DPIHFP), and BAPO. Groups with unitary photoinitiator systems (BAPO and CQ), binary (BAPO+EDAB, BAPO+DPIHFP and CQ+EDAB), ternary (BAPO+CQ+EDAB, BAPO+CQ+DPIHFP, BAPO+EDAB+DPIHFP and CQ+EDAB+DPIHFP) and quaternary (BAPO+CQ+EDAB+DPIHFP) were formulated for evaluation. Real-time Fourier transform infrared spectroscopy was used to investigate the PK and test mini-bending to evaluate σ and E. Results When only CQ was used, a slow polymerization reaction was observed and a lower monomer conversion. When only BAPO was used as photoinitiator an increase in the polymerization rate was observed and conversion was higher than CQ+EDAB. The ternary system (BAPO+EDAB+DPIHFP) showed the highest polymerization and conversion rate, in short photo-activation time. Significance BAPO it is a potential photoinitiator for the photopolymerization of dental materials. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the effect of phosphoric acid concentration on microshear bond strength (μSBS) of an etch-and-rinse adhesive system to demineralized irradiated enamel. Background data: Er:YAG laser irradiation may increase acid resistance of enamel; however, its use is associated with reduced bonding effectiveness. Materials and methods: Three experimental etching agents and one bonding agent were fabricated. Enamel pretreatment was tested in two levels (bur and laser) and phosphoric acid was tested in four levels (control and at 35, 45, or 55%). Commercially available phosphoric acid and a bonding agent were used as control. Enamel samples were submitted to a pH-cycling model to induce demineralization. Half of the exposed demineralized enamel area was prepared with diamond bur and half was prepared with an Er:YAG laser (λ=2.94 μm, 300 mJ, 2 Hz). Specimens were randomly allocated to receive different acid etching concentrations and either the experimental or the commercial adhesive system. Microshear bond strength and the adhesive remnant index (ARI) scores were determined. μSBS's data were evaluated by two way analysis of variance (ANOVA) and Tukey's test. Kruskal-Wallis followed by Dunn's method and Mann-Whitney test were used for ARI comparisons (α=5%). Results: For μSBS, no significant difference among the groups was found, either for phosphoric acid concentration or surface preparation. For ARI scores, statistically higher resin retention was found for lased groups ( p<0.001). Conclusions: The increase of phosphoric acid concentration did not impair bond strength regardless of surface preparation; however, increased retention was found when demineralized enamel was prepared with laser. [ABSTRACT FROM AUTHOR]

Because of the need for more effective and less harmful antifungal therapies, and interest in the synthesis of new carboximidamides, the goal of this study was to determine the antifungal and anti-enzyme activities of some new pyrazole carboximidamides and their cytotoxicity. For this purpose, tests were performed to evaluate: minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC); production of proteinases and phospholipase, and cytotoxicity of the extracts. Data were analyzed by ANOVA and Tukey Tests (α = 5%). The results were: MIC and MFC ≥ 62.5 μg/mL (C. albicans, C. parapsilosis, C. famata, C. glabrata, and Rhodotorula mucillaginosa) and MIC and MFC ≥ 15.6 μg/mL (C. lipolytica). The values of proteinase and phospholipase (Pz) of C. albicans before and after exposure to the compounds were: 0.6 (±0.024) and 0.2 (±0.022) and 0.9 (±0.074) and 0.3 (±0.04), respectively. These proteinase results were not significant (p = 0.69), but those of phospholipase were (p = 0.01), and 15.6 μg/mL was the most effective concentration. The cytotoxicity means were similar among the tests (p = 0.32). These compounds could be useful as templates for further development through modification or derivatization to design more potent antifungal agents. Data from this study provide evidence that these new pyrazole formulations could be an alternative source for the treatment of fungal infections caused by Candida. However, a specific study on the safety and efficacy of these in vivo and clinical trials is still needed, in order to evaluate the practical relevance of the in vitro results. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The aim of this study was to evaluate the calcium release, pH, flow, solubility, water absorption, setting and working time of three experimental root canal sealers based on mineral trioxide aggregate (MTA) and two forms of calcium phosphates (CaP). Methods: The materials were composed of a base and a catalyst pastes mixed in a 1:1. The base paste was made by 60% bismuth oxide and 40% butyl ethylene glycol disalicylate. Three different catalyst pastes were formulated containing 60% MTA or 40% MTA+20% CaP (hydroxyapatite HA or dibasic calcium phosphate dehydrate DCPD), 39% Resimpol 8% and 1% titanium dioxide. MTA Fillapex was used as control. The release of calcium and hydroxyl ions, solubility and water absorption were measured on regular intervals for 28 days. The working time and flow were tested according to ISO 6876:2001 and the setting time according to ASTM C266. The data were analyzed using 1-way ANOVA with Tukey's test (p <.01). Results: All the cements showed basifying activity and released calcium ions. MTA Fillapex showed the highest values of flow (p <.01) and working/setting times (p <.01) and the smallest values of solubility (p <.01) and water absorption (p <.01). Significance: All experimental materials showed satisfactory physical–chemical properties to be used as endodontic sealers in clinical practice. [Copyright &y& Elsevier]

This study evaluated the performance of different bonding tests on the bond strength of three adhesive systems to dentin. Forty-eight bovine incisors were used in the study, which were allocated in two groups according to the bond strength test performed: microtensile (µTBS) or microshear (µSBS). Also, each group was divided in three subgroups according to the adhesive system applied: Single Bond (SB), Prime & Bond (PB) and XP Bond (XPB) (n=8). The teeth were prepared according to each bond strength test protocol, and then the specimens were tested in an universal testing machine (EMIC). The data were submitted to two-way ANOVA (bond strength test and adhesive system type factors) and Tukey's post hoc test (α=0.05). The µTBS results were higher for all the adhesives when compared to the µSBS ones. Within the µTBS results, SB showed higher bond strength than PB and XPB, which showed similar adhesive performance among each other; within the µSBS results, all the adhesives presented similar bond strength values to dentin. The µTBS test detected differences between the adhesive systems evaluated; in contrast, the µSBS test was less discriminating in evaluating the adhesive performance of the materials tested. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study is to evaluate the hypothesis that replacing 2-hydroxyethyl methacrylate (HEMA) for surfactant dimethacrylates (SD) does not affect the immediate and long-term microtensile bond strength (μTBS) of experimental two-step self-etch HEMA-free adhesive systems applied on dentin. Materials and methods: Five experimental HEMA-free two-step self-etching systems containing different SD (ethoxylated bisphenol A diglycidyl dimethacrylate (Bis-EMA 10, B10), Bis-EMA 30 (B30), poly-ethyleneglycol (400) dimethacrylate (PEG 400, P400), PEG 1000 (P1000), and PEG 400 urethane dimethacrylate (UDMA) (UP400)) and a HEMA-containing system (control) (HA) were formulated. Specimens were subjected to the μTBS test after 24 h and 6 and 12 months of storage. Data (in megapascals) were analyzed by Kruskal-Wallis and Dunn tests ( α = 0.05). Results: Medians of the μTBS data after 24 h of storage are: HA = 57.2, B10 = 26.2, B30 = 24.0, P400 = 32.6, P1000 = 37.3, and UP400 = 57.9; after 6 months are: HA = 47.9, B10 = 18.5, B30 = 7.8, P400 = 16.1, P1000 = 14.6, and UP400 = 51.6; and after 12 months are: HA = 31.2, B10 = 15.2, B30 = 9.0, P400 = 9.1, P1000 = 13.3, and UP400 = 35.7. Between the HEMA-free groups, the adhesive system formulated with PEG 400 UDMA produced similar μTBS to the HEMA-containing group. Also, the storage of specimens decreased the μTBS ( p < 0.05). Conclusion: Replacing HEMA for PEG 400 UDMA in an adhesive system formulation generated a satisfactory μTBS to dentin. Clinical relevance: Surfactant dimethacrylates have a potential use in the development of HEMA-free self-etching adhesive systems, which are more chemically stable. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to investigate the cytotoxicity and 1-year dentin bond stability of solvated etch-and-rinse dental adhesives based on tetrahydrofuran (THF), acetone, or ethanol, containing water or not. Materials and methods: Seven primers were prepared using the following solvents: THF, acetone, ethanol, water, THF/water, acetone/water, and ethanol/water. Bovine dentin was used, and specimens for microtensile bond strength (μTBS) test were prepared. Specimens were tested after storage in distilled water for 24 h or 1 year. Cytotoxicity of the solvents was evaluated in 3T3/NIH mouse fibroblasts using a colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after exposure for 24 h. Results: No significant differences were detected among solvents after storage for 24 h, except for the water-based group, which showed the lowest μTBS values. After storage for 1 year, the THF-based adhesive system resulted in more stable bonds. Yet, THF showed an intermediate cytotoxicity when compared with the other solvents, being less toxic than phosphate monomer and similar to 2-hydroxyethyl methacrylate. Conclusion: THF seems to be a suitable solvent for adhesive systems. Clinical relevance: THF is a promising solvent that can be used to improve dentin bond stability. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: The purpose of this study was to evaluate the reactivity and polymerization kinetics behavior of a model dental adhesive resin with water-soluble initiator systems. Methods: A monomer blend based on Bis-GMA, TEGDMA and HEMA was used as a model dental adhesive resin, which was polymerized using a thioxanthone type (QTX) as a photoinitiator. Binary and ternary photoinitiator systems were formulated using 1mol% of each initiator. The co-initiators used in this study were ethyl 4-dimethylaminobenzoate (EDAB), diphenyliodonium hexafluorophosphate (DPIHFP), 1,3-diethyl-2-thiobarbituric acid (BARB), p-toluenesulfinic acid and sodium salt hydrate (SULF). Absorption spectra of the initiators were measured using a UV–Vis spectrophotometer, and the photon absorption energy (PAE) was calculated. The binary system camphorquinone (CQ)/amine was used as a reference group (control). Twelve groups were tested in triplicate. Fourier-transform infrared spectroscopy (FTIR) was used to investigate the polymerization reaction during the photoactivation period to obtain the degree of conversion (DC) and maximum polymerization rate (R p max) profile of the model resin. Results: In the analyzed absorption profiles, the absorption spectrum of QTX is almost entirely localized in the UV region, whereas that of CQ is in the visible range. With respect to binary systems, CQ+EDAB exhibited higher DC and values. In formulations that contained ternary initiator systems, the group CQ+QTX+EDAB was the only one of the investigated experimental groups that exhibited an value greater than that of CQ+EDAB. The groups QTX+EDAB+DPIHFP and QTX+DPIHFP+SULF exhibited values similar to those of CQ+EDAB with respect to the final DC; however, they also exhibited lower reactivity. Significance: Water-soluble initiator systems should be considered as alternatives to the widely used CQ/amine system in dentin adhesive formulations. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the influence of an iodonium salt on the immediate and long-term microtensile bond strength to dentin of an experimental dental two-step, self-etching adhesive system. A model dental adhesive resin was formulated using bisphenol A glicidyl dimethacrylate (Bis-GMA), triethylene glicol dimethacrylate (TEGDMA), and hydroxyethyl methacrylate (HEMA), which was polymerized using four combinations of photo-initiators and coinitiators. A group using only camphorquinone (CQ), two binary systems (CQ and ethyl 4-dimethylamine benzoate (CQ+EDAB), CQ and diphenyliodonium hexafluorphosphate (CQ+DPIHFP)) and a ternary system (CQ+EDAB+DPIHFP) was investigated. Clearfil SE Bond (CSEB) was used as a commercial reference. Bond strength to bovine dentin was assessed through microtensile bond tests measured in MPa in a universal testing machine. The beam specimens were stored in distilled water at 37°C for 24h and 1 year. Two-way ANOVA and Student–Newman–Keuls'' post-hoc tests were used to compare means of groups (α=5%) and failure modes classified under magnification. After 24h, the ternary system showed a bond strength similar to that of the binary system CQ+EDAB and the commercial material. After 1 year of storage, the μTBS values of the group CQ+EDAB+DPIHFP showed a bond strength significantly higher (p<0.05) than those of the CQ, CQ+DPIHFP, and CQ+EDAB groups and no difference from that of the CSEB group. The ternary photo-initiator system with iodonium salt maintained increased bond strength to dentin of model self-etching adhesive systems after 1 year of aging. [Copyright &y& Elsevier]

Carbon nanostructures and nanocomposites display versatile allotropic morphologies, physico-chemical properties and have a wide range of applications in mechanics, electronics, biotechnology, structural material, chemical processing, and energy management. In this study we report the synthesis, characterization, and biotechnological application of cobalt magnetic nanoparticles, with diameter approximately 15-40 nm, embedded in carbon structure (Co/C-MN). A single-step chemical process was used in the synthesis of the Co/C-MN. The Co/C-MN has presented superparamagnetic behavior at room temperature an essential property for immunoseparation assays carried out here. To stimulate interactions between proteins and Co/C-MN, this nanocomposite was functionalized with acrylic acid (AA). We have showed the bonding of different proteins onto Co/C-AA surface using immunofluorescence assay. A Co/C-AA coated with monoclonal antibody anti-pathogenic Leptospira spp. was able to capture leptospires, suggesting that it could be useful in immunoseparation assays. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of zinc methacrylate (ZM) on the inhibition of matrix metalloproteinase 2 (MMP-2) and the ultimate tensile strength (UTS) of an experimental polymer. Enzymes secreted from mouse gingival tissues were analyzed by gelatin zymography in buffers containing 5 mM CaCl (Tris-CaCl) in 50 mM Tris-HCl buffer with various concentrations of ZM (0.5, 1, 2, 4, 8, and 16 mM). The matrix metalloproteinases present in the conditioned media were characterized by immunoprecipitation. The polymer UTS evaluation was performed in eight groups with various concentrations of ZM (0, 0.5, 1, 2.5, 5, 10, 20, and 30 wt.%), in a mechanical testing machine. MMP-2 (62 kDa) was detected in the zymographic assays and inhibited by ZM in all tested concentrations. UTS data were submitted to one-way ANOVA and Tukey's test ( α = 0.05), and no significant differences were observed among groups, except in the polymer containing 30% ZM, presenting a significantly lower value when compared with the control group ( p < 0.05). The results suggest that ZM inhibits MMP-2 expression in all concentrations tested, while small concentrations did not affect the ultimate tensile strength of the polymer. Zinc methacrylate is a metalloproteinase inhibitor that can be copolymerized with other methacrylate monomers. Yet, the addition of ZM did not affect the resin bond strength. Thus, in vivo tests should be performed to evaluate the performance of this material. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of different concentrations of triethylene glycol dimethacrylate (TEGDMA) on the inhibition of matrix metalloproteinase 2 (MMP-2). Mouse gingival explants were cultured overnight in DMEM and the expression of secreted enzymes was analyzed by gelatin zymography in buffers containing 5 mM CaCl (Tris-CaCl) in 50 mM Tris-HCl buffer with the addition of TEGDMA at different concentrations (0.62%, 1.25%, 2.5%, or 5.0% (v/v)). The gelatinolytic proteinase present in the conditioned media was characterized as matrix metalloproteinase by means of specific chemical inhibition. The matrix metalloproteinases present in the conditioned media were characterized as MMP-2 by immunoprecipitation. The eletrophoretic bands were scanned and the transmittance values were analyzed. Data was plotted and submitted to linear regression to investigate MMP-2 inhibition as a function of TEGDMA concentration. Three major bands were detected in the zymographic assays. These bands were characterized as MMP-2. Zymogene (72 kDa), intermediate (66 kDa) and active forms of MMP-2 (62 kDa) were inhibited by TEGDMA in a dose-dependent way. These findings suggest that TEGDMA could inhibit MMP-2 expression even at small concentrations. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated the effect of the concentration of acidic functional monomer on the dentin bond stability of a model two-step, self-etch adhesive system. Six self-etch primers were formulated using hydroxyethyl methacrylate (HEMA), 1,3-glycerol dimethacrylate phosphate (GDMA-P), ethanol and water. Different mass concentrations of GDMA-P were tested: 0, 15, 30, 50, 70 or 100% (primers labeled P0–100). The pH of the solutions was measured. The bonding resin was composed of (di)methacrylates. Bond strength to bovine dentin was assessed through a microtensile bond test. The beam specimens were stored in distilled water, at 37°C, for 24h, 6 months or 1 year. Data were statistically analyzed and failure modes classified under magnification. The increase in acidic monomer concentration was associated with an exponential decrease in pH (R 2 =0.999; P<0.001). All specimens debonded prematurely for the primers P 0, P 70 and P 100. After 24h, the bond strengths for P 50>P 30=P 15. After 6 months and 1 year, P 50=P 30>P 15. The bond strength after 6 months was similar to 24h for P 15 and P 50, but significantly lower after 1 year. P 30 showed no differences in bond strength over the 1-year storage period. A predominance of mixed failures was detected for all primers at 24h. After 6 months, P 30 and P 50 showed a predominance of adhesive failures. After 1 year, the predominant failure mode for all primers was cohesive within dentin. In conclusion, a mass fraction of 50% of phosphate monomer is a limit to be added to self-etch primers; a more stable longevity of the bonds was obtained with the primer with 30% of phosphate methacrylate. [Copyright &y& Elsevier]

This study evaluated the performance of composite restorations placed with two matrix and wedge systems 4 years after placement. In a split-mouth design, 23 patients were selected and received at least two class II restorations, one with metallic matrix and wooden wedge and the other with polyester matrix and reflective wedge. One dentist placed the 109 restorations, and all cavities were restored using Single Bond and P-60 (3M ESPE) according to the manufacturer's instructions. Polymerization was performed through occlusal (metallic matrices) or through the reflective wedge (polyester matrices). Restorations were evaluated and categorized as alpha (A), bravo (B), charlie (C), and delta (D; modified United States Public Health System criteria) at baseline and 4 years after placement. Both clinical aspects and interproximal radiographs were considered in the evaluation. Data were analyzed with Mann-Whitney and Friedman tests ( α = 0.05). Fifteen subjects (78 teeth/102 proximal surfaces) were reassessed after 4 years. Considering comparisons within matrices in different evaluation time points, no significant differences were observed ( p > 0.05). Comparing 4-year to baseline results, the quality of marginal adaptation (40% and 40.4 %, score A), marginal staining (31.3% and 28.8%, score A), and roughness (56% and 46.2%, score A) decreased for metallic and translucent matrices, respectively ( p < 0.05), while color match (9.6%, score A), occlusal contacts (75%, score A), and proximal contacts (71.7%, score A) also decreased in quality for translucent matrices ( p < 0.001). Although the matrix and wedge systems evaluated showed similar clinical performance, there was clinical quality loss after 4 years, with most of the restorations being still acceptable, and no intervention was necessary. [ABSTRACT FROM AUTHOR]

In this study the influence of water concentration in self-etching (SE) primers on their aggressiveness and bond strength to ground enamel was investigated. Five experimental primers with 0, 5, 10, 20, or 40 wt% of water were formulated, using Clearfil SE Bond® (CSEB) as a commercial reference. Primers were applied to bovine incisors following application of bonding resin and composite restoration. Bond strength was evaluated through shear testing and data were statistically analyzed (5%). The etching aggressiveness was evaluated by SEM. Water concentration significantly affected bond strength and etching aggressiveness. The highest bond strength value (MPa) was found for the primer containing 20% of water (24.7), followed by CSEB (23.8). Groups containing 5% (20.5) and 10% (20.2) of water showed an intermediate performance, while the lowest values were observed for the 0% (17.3) and 40% (16.7) groups. SEM analysis showed increasing aggressiveness for increased water content. [ABSTRACT FROM AUTHOR]