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Fabiano Augusto Dos Santos Janisch,1 Milagros Falcon Aguilar,2 Flávio Henrique Baggio Aguiar,2 Fabiana Mantovani Gomes França,1 Roberta Tarkany Basting,1 Waldemir Francisco Vieira-Junior2 1Department of Restorative Dentistry, Faculdade São Leopoldo Mandic, Campinas, SP, Brazil; 2Department of Restorative Dentistry, Faculdade de Odontologia de Piracicaba, Universidade Estadual de Campinas, Piracicaba, SP, BrazilCorrespondence: Waldemir Francisco Vieira-Junior, Faculdade de Odontologia de Piracicaba, Universidade, Estadual de Campinas, Av. Limeira, 901 – Areião, Piracicaba, SP, Brazil, Tel +55 (19) 21065220, Email waljr@unicamp.brObjective: This study aimed to evaluate the in vitro effects of coffee exposure on the color and roughness of conventional and bulk-fill resin composites, with and without surface pre-reacted glass-ionomer (S-PRG) filler.Methodology: Forty-eight cylindrical samples (Ø 6 mm × 2 mm) were prepared and categorized as follows (n = 12 per group): conventional nano-hybrid (Tetric N-Ceram, Ivoclar); nano-hybrid with S-PRG filler (Beautifil II, Shofu); bulk-fill (Tetric N-Ceram Bulk Fill, Ivoclar); and bulk-fill with S-PRG filler (Beautifil Bulk Restorative, Shofu). The samples were assessed for surface roughness (Ra, μm), color coordinates (CIE Lab), and overall color change (ΔEab, ΔE00). Measurements were taken at baseline and after 7 days of coffee immersion (pH = 4.95). Data were analyzed using generalized linear models, Kruskal–Wallis, Dunn, and paired Wilcoxon tests (α = 0.05).Results: After the coffee exposure, all resin composites exhibited a significant decrease in L&ast; (towards black), an increase in a&ast; (towards red), an increase in b&ast; (towards yellow), and a higher Vita color score (p < 0.05). Tetric N-Ceram demonstrated the lowest roughness values post-exposure; however, a significant increase in roughness over time was observed only for Tetric N-Ceram Bulk Fill (p < 0.05). For ΔEab, Beautifil Bulk Restorative and Tetric N-Ceram showed higher values compared to Beautifil II. For ΔE00, a significant difference was noted between Beautifil Bulk Restorative and Beautifil II (p < 0.05).Conclusion: Resin composites with S-PRG fillers exhibited similar pigmentation dynamics to conventional composite but showed greater surface roughness after exposure to coffee. Considering the S-PRG materials, the bulk-fill version is more susceptible to staining.Keywords: composite resins, coffee, color, surface properties

Physical and mechanical properties of high-viscosity bulk-fill resin composites submitted to additional polymerization for semi-direct use were evaluated. Filtek Z350 XT, Aura Bulk Fill, Beautifil Bulk Restorative, Filtek One Bulk Fill Restorative, and Tetric N-Ceram Bulk Fill were submitted to additional polymerization to evaluate sorption, solubility, surface microhardness, surface roughness before and after simulated brushing, color stability after coffee staining, flexural strength, elastic modulus, and modulus of resilience. Filtek Z350 XT and Filtek One Bulk Fill Restorative showed higher sorption values, while Aura Bulk Fill showed higher solubility (p<0.0001). Microhardness values were significantly higher for Filtek Z350 XT (p<0.0001). Roughness increased after wear for all resins (p<0.05). All resins exhibited staining, with significantly higher ΔEab, ΔE00, and ΔWID values observed for Beautifil Bulk Restorative (p<0.0001). Flexural strength values were higher for Filtek Z350 XT and Filtek One Bulk Fill Restorative in comparison with the others (p<0.0001). Filtek One Bulk-Fill had higher elastic modulus and modulus of resilience values (p<0.0001). Physical and mechanical properties varied according to the composition. None of the bulk-fill resins showed surface microhardness and roughness properties after brushing similar to or superior to those of the conventional type. Color stability after staining depended on resin composition, with Beautifil Bulk Restorative showing more intense staining., (©Operative Dentistry, 2025.)

The color and the surface roughness of aesthetic restorations are related to the clinical sucess and longevity of these treatments. Aim: This study evaluated the influence of finishing and polishing systems, and storage media on the surface roughness and color stability of aesthetic restorative composites. Materials and Method: Cylindrical specimens (n=10) were prepared and treated according to: 1. Type of composite resin (nanofilled- Filtek Z350XT, suprananofilled- Estelite Omega, nanohybrid- Empress Direct); 2. Type of finishing and polishing systems (no polishing, aluminum oxide discs or abrasive rubber polishers); and 3. Type of immersion medium (water or coffee, 3 h/day/30 days). Surface roughness (Ra - μm) and color stability (L, ΔEab, and ΔE00) were evaluated at baseline (after polishing) and final time (after immersion). Data were subjected to Kruskal-Wallis, Mann-Whitney, Wilcoxon, and Student-Newman-Keuls tests (α=0.05). Results: Nanohybrid (p<0.001) and suprananofilled composite resins (p=0.004) showed an increase in Ra after polishing, regardless the finishing and polishing system. After immersion in coffee, the nanofilled composite had the highest roughness values (p=0.032). L values increased for all resins after polishing (p<0.05). Suprananofilled composites had the greatest color stability with the lowest values of ΔEab and ΔE00. Conclusions: Finishing and polishing systems had an impact on the surface roughness and color stability of all aesthetic resins, and their effectiveness depended on the type of composite resin., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article, (SAIO.)

Purpose: To evaluate color change in ceramic veneers luted to enamel with light-cured, dual-cured resin luting agents, or heated resin composites, as well as to evaluate microhardness and diametral tensile strength of these luting agents., Methods: For color analysis, 0.5 mm-thick leucite-reinforced glass ceramic veneers (IPS Empress CAD) were cemented onto 40 bovine dental blocks (n= 10) using RelyX Ultimate (RU) or RelyX Veneer (RV) resin-based luting agents, or Gradia Direct (GD) and Palfique Lx5 (P) heated resin composites. After luting, the specimens were subjected to thermocycling (10,000 cycles). Color analysis was performed before and after thermocycling (L*, a*, b*, ΔEab, ΔE₀₀). For the microhardness (Knoop) and diametral tensile strength tests, specimens (Ø 6 x 2 mm) were made (RU, RV, GD, and P). The specimens were subdivided into eight groups (n=10) and light-cured through different ceramic sheets (thicknesses of 0.5 mm or 1.5 mm). Knoop microhardness was performed on the top surface in a microhardness tester, and diametral tensile strength on a universal testing machine. Data were submitted to statistical analysis, using two-way ANOVA, Tukey, and Kruskal-Wallis tests (α= 0.05)., Results: For the general color alteration, there was no statistically significant difference between the luting materials (ΔEab, P= 0.57; ΔE₀₀, P= 0.50). There was no interaction between luting agent and thermocycling, for L* (P= 0.87), a* (P= 0.97) and b* (P= 0.95) values. Thermocycling significantly affected only the L* values (P= 0.047), which increased after the cycles. For microhardness, there was a statistically significant difference considering luting agents and ceramic thickness (P< 0.001). GD heated resin composite presented significantly lower microhardness values than all other materials, at both ceramic thicknesses. At a thickness of 1.5 mm, RU cement had higher microhardness values than RV and P materials. Diametral tensile strength was significantly influenced by luting agent (P= 0.01), but not by ceramic thickness (P= 0.55). Diametral tensile strength of GD resin composite was higher than that of the RU, but neither of these two materials differed from RV and P., Clinical Significance: Heated resin composite, used as luting agents, showed similar color stability to light-cured and dual-cure resin cements, however its microhardness was affected by ceramic thickness., Competing Interests: The authors declared no conflicts of interest., (Copyright©American Journal of Dentistry.)

Over the past few years, insects have been used as samplers of vertebrate diversity by assessing the ingested-derived DNA (iDNA), and dung beetles have been shown to be a good mammal sampler given their broad feeding preference, wide distribution and easy sampling. Here, we tested and optimized the use of iDNA from dung beetles to assess the mammal community by evaluating if some biological and methodological aspects affect the use of dung beetles as mammal species samplers. We collected 403 dung beetles from 60 pitfall traps. iDNA from each dung beetle was sequenced by metabarcoding using two mini-barcodes (12SrRNA and 16SrRNA). We assessed whether dung beetles with different traits related to feeding, nesting and body size differed in the number of mammal species found in their iDNA. We also tested differences among four killing solutions in preserving the iDNA and compared the effectiveness of each mini barcode to recover mammals. We identified a total of 50 mammal OTUs (operational taxonomic unit), including terrestrial and arboreal species from 10 different orders. We found that at least one mammal-matching sequence was obtained from 70% of the dung beetle specimens. The number of mammal OTUs obtained did not vary with dung beetle traits as well as between the killing solutions. The 16SrRNA mini-barcode recovered a higher number of mammal OTUs than 12SrRNA, although both sets were partly non-overlapping. Thus, the complete mammal diversity may not be achieved by using only one of them. This study refines the methodology for routine assessment of tropical mammal communities via dung beetle 'samplers' and its universal applicability independently of the species traits of local beetle communities., (© 2024 John Wiley & Sons Ltd.)

Background: To evaluate the effect of different finishing and polishing systems on the surface roughness and color changes of bis-acryl (Protemp 4 - 3M ESPE- St. Paul, USA; Structur 3 - Voco, Cuxhaven, Germany) and chemically activated acrylic materials (Duralay - Reliance, SP, Brazil)., Material and Methods: Specimens (10 x 2 mm) thick were prepared for each material. The specimens were subjected to polishing and finishing procedures with aluminum oxide discs (Diamond Master - FGM, Joinville, Santa Catarina, Brazil) and spiral rubber disks (Sof-Lex - 3M ESPE, Germany). The control did not receive any polishing and finishing procedures. Surface roughness and color measurement values were obtained after the finishing and polishing procedures and immediately after 30 days of storage in water, coffee, and red wine. Data for each material were analyzed by One-Way ANOVA ( p <0.05)., Results: The polishing with aluminum oxide discs was able to affect the initial surface roughness values of chemically activated acrylic material ( p <0.05). After immersion in staining solutions, lower ∆E values were only observed for the bis-acryl composite resins compared to the control group ( p <0.05)., Conclusions: The finishing and polishing systems influenced the surface roughness and color stability of the materials tested. The chemically activated acrylic resin showed lower surface roughness and higher color stability than the bis-acryl materials. Key words: Acrylic resin, bis-acryl resin, provisional restoration., Competing Interests: The authors deny any conflicts of interest relevant to this study., (Copyright: © 2024 Medicina Oral S.L.)

Glass ceramics are widely used to manufacture esthetic veneers, inlays, onlays, and crowns. Although the clinical survival rates ofglass-ceramic restorations arefavorable,fractures or chips are common. Certain cases can be repaired with direct composite., Aim: The aim of this study was to investigate the interaction effect of different designs and surface treatments on the load-to-failure of lithium disilicate glass-ceramic repaired with nanofilled composite., Materials and Method: Lithium-disilicate glass-ceramic slabs (IPS e.max Press, Ivoclar Vivadent) with three different designs of the top surface (flat, single plateau, or doubleplateau) (n=U) received 'no treatment', '5% HF etching', or "AI2O3 sandblasting". HF-etched and sandblasted slabs also received silane and universal one-step adhesive application. All slabs were incrementally repaired with nanofilled composite (Filtek Z350, 3M ESPE) up to6 mm above the highest ceramic top plateau. Specimens were stored in artificial saliva at 37 °C for 21 days and then subjected to 1,000 thermocycles between 5 and 55 °C. The interface composite-ceramic of each specimen was tensile tested until failure in a universal testing machine and the mode of failure was determined under a stereomicroscope. The ceramic surface morphology of one representative tested specimen from each subgroup (design/surface treatment) was observed through scanning electron microscopy (SEM)., Results: Regardless of ceramic design, the absence of surface treatment resulted in significantly lower load-to-failure values. No significant differences in load-to-failure values were observed between HF-etched and sandblasted specimens for the flat design; however, HF etching resulted in significantly higher load-to-failure values than sandblasting for both single plateau and double plateau designs. The majority (60%) of HF-etched specimens with single plateau or double plateau presented mixed failures. SEM photomicrographs showed that HF-etched specimens had smoother surfaces than sandblasted specimens., Conclusion: The surface treatment of a defective lithium disilicate glass-ceramic restoration has more influence than its macroscopic design on the retention of the composite repair. HF etching seems to provide higher bond strength to the composite repair., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article., (Copyright© 2024 Sociedad Argentina de Investigación Odontológica.)

Atrazine (ATZ) is the third most sold herbicide in Brazil, occupying the seventh position between most widely used pesticides. Due to its easy outflow, low reactivity and solubility, moderate adsorption to organic matter and clay, and long soil persistence, residual herbicide can be identified after long periods following application, and its usage has been prohibited in diverse countries. Amphibians are important bioindicators to assess impact of pesticide like atrazine, due to having a partial aquatic life cycle. This study had as objective to assess the response of bullfrog ( Lithobates catesbeianus ) tadpoles when exposed to this herbicide. Animals were exposed for a total of 168h to following concentrations: negative control, 40 μg/L, 200 μg/L, 2000 μg/L, 20000 μg/L of ATZ. Analysis of swimming activity was performed, and biochemical profile was assessed by analysis of blood and plasma glucose levels, urea, creatinine, cholesterol, HDL, triglycerides, glutamic pyruvic transaminase (GPT), alkaline phosphatase (AP), calcium, total proteins, phenol, peroxidase and polyphenol oxidase activity. Results exhibited malnutrition, anemia, likely muscle mass loss, and hepatic damage, indicating that ATZ can lead to an increase in energy to maintain homeostasis for animal survival.

Purpose: To evaluate the impact of simplified or multi-step polishing techniques on the roughness, color, and susceptibility to staining of different resin composites., Methods: Discs (Ø6 mm x 2 mm) were obtained from different resin composites [nanofilled (Z350XT), suprananofilled (Estelite Omega), and nanohybrid (Forma)]. The specimens (n= 15) were submitted to a simplified protocol using abrasive discs (Sof-Lex) and spiral discs (Diacomp Plus Twist), or a multi-step protocol using abrasive discs (Sof-Lex), abrasive points (Jiffy), silicon carbide brush and felt disc with diamond pastes (Diamond Polish). The specimens were evaluated initially for roughness (Ra) and color (CIEL*a*b*, CIEDE 2000), after completing the polishing protocol, and after exposure to a coffee solution (pH= 5.01). The data were analyzed according to the variables, using generalized linear models, and the Friedman, Nemenyi, Kruskal-Wallis, Dunn, and Mann-Whitney tests (α= 0.05)., Results: The nanohybrid resin composite showed an increase in Ra following use of both polishing methods (P= 0.038). Both techniques promoted an increase in L* values after polishing; however, the general color changes (ΔEab and ΔE₀₀) were greater after the multi-step polishing (P< 0.05). After immersion in coffee, the multi-step polished groups of the nanohybrid and suprananofilled resin composite showed higher L* values than the simplified polishing groups (P= 0.023), and the nanofilled resin composite showed higher ΔEab and ΔE₀₀ values than the other resin composites, regardless of the polishing technique (P< 0.05)., Clinical Significance: The choice of the resin composite had a greater effect on roughness, color stability and susceptibility to staining than the polishing technique. However, luminosity after coffee staining was higher with the multi-step polishing technique., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.

Based on its mechanical properties, PEEK (polyether-ether-ketone) might be useful in restorative procedures. In oral rehabilitation, its viability has been studied mainly for prostheses and dental implants., Aim: The aim of this study was to evaluate the fit accuracy of dental implant bars made of either PEEK or cobalt-chrome submitted to cycling mechanics., Materials and Method: This was an experimental in vitro study, where units were treated with two implants and mini-abutments, joined by cobalt-chrome or polyether-ether-ketone PEEK bars. A total 20 bars were prepared (n=10 per group) and subjected to mechanical cycling tests (1 million cycles on the distal cantilever of the bar in the vertical direction, 120N and sinusoidal loading, at a frequency of 2Hz). The fit at the abutment/implant interface was measured before and after cycling, and the counter-torque of the vertical screw of the mini abutments was measured after cycling, using a digital torquemeter. Data were analyzed by three-way ANOVA and Tukey's test at 5% significance level., Results: No statistically significant interaction was found among the three factors considered (bar material, implant positioning and mechanical cycling) (p = 0.592). No significant difference was identified in the interaction between bar material and implant positioning (p = 0.321), or between implant positioning and mechanical cycling (p = 0.503). The association between bar material and mechanical cycling was statistically significant (p = 0.007), with the cobalt-chrome bar resulting in greater misfit with mechanical cycling. There was no difference in counter-torque values between groups., Conclusions: The PEEK bar provided better fit of the mini abutments to the implants, even after mechanical cycling. The counter-torque of the screws was similar in all scenarios considered., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article.

During the manufacture of ceramic restorations there is an important step of finishing and polishing and the effects of different types of these procedures on the surface characteristics of ceramics are not known for sure., Aim: To evaluate the effects of various surface treatments and immersion in coloring substances on the roughness, microhardness, and color stability of CAD-CAM monolithic ceramics., Materials and Method: The ceramics used were lithium disilicate reinforced with zirconium dioxide (Suprinity), lithium disilicate (E.max) or leucite (Empress). They were subjected to two surface treatments: glazing (group G) (n=20) or mechanical polishing (group P) (n=20). Then they were divided into two subgroups (n=10) to be treated with the staining substance (coffee or water). Roughness, microhardness and color were measured before and after treatment. Data were subjected to analysis of variance and multiple comparisons were performed with Tukey tests at 5% significance level., Results: Roughness was lower in all tested ceramics after polishing than after glazing. Microhardness was the same for polished and glazed E.max, higher in glazed than polished Empress, and higher in polished than glazed Suprinity. Analysis of the effects of glazing and polishing on the individual ceramics showed that the ΔE2000 and ΔWID data of the E.max ceramic subjected to polishing showed greater change. Mechanical polishing is a good option for surface treatment of monolithic ceramics., Conclusion: Glazing was inferior and less satisfactory than polishing. Glazing generates changes that can lead to color instability., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article.

Purpose: To evaluate the effect of different varnishes on dentin permeability to erosive/abrasive challenges., Methods: 60 superficial dentin discs were randomly allocated to six groups (n=10): Duraphat, PRG Barrier Coat, Clinpro XT, Profluorid, Fluor Protector S and untreated (control). Permeability tests were carried out: after acid conditioning, after treatment, and after abrasive/erosive challenges. The abrasive-erosive challenges were performed for 5 days (citric acid and in remineralizing saliva), as well as abrasion with toothpaste slurry (Colgate Total 12). Scanning electron microscopy (SEM) images were obtained of the dentin surfaces (5,000x) after the treatments, and after the erosive/abrasive challenges., Results: Kruskal-Wallis and Dunn tests showed that all the varnishes promoted a decrease in dentin permeability directly after application, with Clinpro XT showing the highest percentage (69.52%) of dentin sealing (P= 0.0188). After the erosive/abrasive challenge, only PRG Barrier Coat varnish showed dentin sealing ability with reduced dentin permeability (42.16%) (P= 0.0014). However, none of the applied varnishes promoted a statistically significant difference in the percentage of dentin sealing, compared with the control group (P> 0.05). Clinpro XT showed a higher percentage of dentin sealing, while only PRG Barrier Coat showed reduced dentin permeability after the erosive/abrasive challenge., Clinical Significance: Varnish containing S-PRG filler has the efficacy needed to be used as a coating material to reduce dentin permeability in situations of erosive/abrasive challenges., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Purpose: To evaluate over time the bond strength to dentin of different resin composites (RBCs) associated with the universal adhesive system applied with self-etching or total-etching strategies., Methods: 60 human third molars were obtained, randomly divided into experimental groups (n= 10) according to RBCs: methacrylate-based nanofilled (Z350 XT); low-viscosity Ormocer-based bulk-fill (Admira Fusion X-base Universal); or high-viscosity Ormocer-based bulk-fill composite (Admira Fusion X-tra). The adhesion procedure was performed using a universal adhesive (Futurabond U) applied in self-etching or total-etching mode. Occlusal preparations (Class I) were made, measuring 4 mm in mesiodistal length, 4 mm in depth, and 3 mm in buccolingual height. The cavities were restored considering the RBCs and adhesive strategies, and the light curing was performed using a LED unit (BluePhase) as recommended by the manufacturers. For this, the nanofilled RBCs were inserted by the oblique incremental technique while the bulk-fill RBCs were inserted in single increments. The samples were stored in water for 24 hours in an oven; to be sectioned, the sticks were randomly separated, stored in distilled water for 24 hours (immediate) or 12 months (long-term), and taken to the universal machine for a microtensile test (MPa). The fractured sticks were examined to classify the type of fracture. The results were analyzed by ANOVA and Tukey's test (α= 0.05)., Results: The MPa values of methacrylate-based nanofilled or high-viscosity Ormocer-based RBC were not affected by the strategy used to apply the universal adhesive system (P> 0.05). However, for the low-viscosity Ormocer-based RBC, higher values were obtained when the total-etching strategy was used compared to the self-etching mode (P< 0.05). After 12 months, when using the total-etching strategy low-viscosity Ormocer-based RBC, higher MPa values were obtained compared to the other materials (P< 0.05)., Clinical Significance: Regardless of the adhesive strategy used, the high-viscosity RBCs, whether based on methacrylate or Ormocer, showed similar adhesive behavior. Low-viscosity Ormocer-based RBC showed greater long-term bond strength associated with the universal adhesive applied in the total-etching strategy., Competing Interests: All authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Purpose: To evaluate the smoothness provided by a one-step finishing and polishing system and its maintenance after hydrothermal aging and brushing of a nanofilled resin composite., Methods: 96 samples of the nanofilled composite Filtek Z350 XT were fabricated, which, after initial average roughness (Ra) analysis, were randomly distributed into three groups, according to the selected finishing and polishing system. The multi-step systems Sof-Lex (aluminum oxide discs) and Jiffy (bullet-shaped abrasive rubbers), and the one-step system OneGloss (bullet-shaped abrasive rubber) were used. After finishing and polishing, a new Ra measurement was performed, and then half of the samples from each group were stored in artificial saliva for 12 months, while the other half underwent aging processes associating hydrothermal cycles (10,000 cycles at 5-55°C) followed by brushing (5,500 strokes), with a mid-abrasive (Crest Cavity Protection) dentifrice slurry, simulating a 12-month period in the oral cavity. Final Ra measurements were performed, and data were analyzed by generalized linear model and Tukey's test (α= 5%)., Results: There was interaction between finishing and polishing system and aging (P< 0.001). The one-step abrasive rubber point provided significantly higher Ra values compared to the multi-step systems, and with the discs there was higher smoothness than with the rubber point sequence. This result was maintained after 12 months in artificial saliva, but after hydrothermal cycles followed by brushing, one-step and multi-step abrasive rubber points no longer significantly differed from each other. Only for the one-step system, hydrothermal cycles followed by brushing significantly reduced Ra., Clinical Significance: Although hydrothermal cycles followed by brushing may have increased the smoothness of nanofilled composite finished and polished with the one-step system, only the multi-step system provided a surface within the roughness threshold to avoid biofilm retention., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Background: Greater degradation of the hybrid layer is expected when a universal adhesive system is used, especially in the conventional application strategy. Therefore, it would important to evaluate the effect of the ethanol (ETH) and a potential matrix protease inhibitor (caffeic acid phenethyl ester/ CAPE) to maximize the ability to achieve stable dentin bond strength. The aim of this study was to evaluated the effect of ETH on a wet-bonding technique, and dentin pretreatments with different concentrations of CAPE in ethanolic solution, followed by application of a universal adhesive system (Single Bond Universal) to inhibit proteolytic activity., Material and Methods: Dentin blocks were allocated to eight experimental groups according to the strategy (total-etch our self-etch) and treatments: ETH, or dentin pretreatment with CAPE (at 0.5%, 2.5%; and 5.0%). Half of each block (each hemiblock) served as the control (without dentin pretreatments) for the same group. The bonding strategy was performed (adhesive system/ restoration with composite resin). Two slices were obtained from each hemiblock and evaluated using in situ zymography. The proteolytic activity was analyzed by quantifying the green photons of the images obtained under a fluorescence microscope in three dentin locations close to the dentin-resin interface: hybrid layer (HL), underlying dentin (UD) and deep dentin (DD)., Results: Wilcoxon tests (for comparison between experimental and control groups) and Friedman and Nemenyi tests (for comparisons between interface locations) showed that there was no difference between the groups with different CAPE concentrations and the respective control groups ( p >0.05). ETH reduced the proteolytic activity at the HL and UD ( p <0.05)., Conclusions: The wet-bonding technique with ETH proved effective in reducing the proteolytic activity. The use of CAPE in different concentrations solubilized in ethanol did not have a favorable effect on proteolytic inhibition. Key words: Adhesives, Hybrid layer, Dentin, Metalloproteinases., Competing Interests: Conflicts of interest The authors have no financial, economic, commercial, and/or professional interest in the topics presented in this manuscript., (Copyright: © 2023 Medicina Oral S.L.)

Atrazine (ATZ) is one of the most used active principles in agricultural systems. This pesticide has the ability to easily accumulate in terrestrial and aquatic environments, causing impacts with chronic adverse effects. Avoidance tests are tests that seek to assess the concentration from which a given organism escapes, that is, migrates to another habitat. They are being used as a modality of innovative and minimally invasive ecotoxicological tests. Our objective was to evaluate the sensitivity and possible toxic effects of ATZ in bullfrog tadpoles (Lithobates catesbeianus), through avoidance tests and oxidative stress analyses. We performed the behavioral avoidance test lasting 12 h, with observations every 60 min in a linear multi-compartment system with seven compartments. Each compartment corresponded to a concentration: negative control, 1, 2, 20, 200, 2000, 20,000 µg L -1 . After the selection of habitat, organisms were forcedly maintained in the chosen concentrations for 48 h and then, metabolic effects were measured assessing the blood plasma amino acid profile and liver protein degradation. We also determined the effective concentrations of ATZ tested at 0 h and 48 h. The results showed that there was an effect of the treatment on the distribution of tadpoles, but not on the hours or on the combined effect (interaction). The biochemical analyses also showed a concentration-dependent relationship which caused significant toxic effects even in a short period of time. In conclusion, these frogs were able to avoid places with high concentrations of ATZ in the first hours of exposure, which suggests that in the natural environment these animals can migrate or avoid areas contaminated by this herbicide; however, depending on the selected concentration, serious biochemical consequences can occur., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The Amazon Forest is one of the world's most biodiverse ecosystems and yet its protected areas are understudied concerning insects and other invertebrates. These organisms are essential for tropical forests due to their ecological processes, with some species being very sensitive to habitat disturbances. Dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae) have been used as bioindicators for more than 30 years and were surveyed to assess the insect biodiversity of two sustainable-use forest reserves in the Brazilian Amazon., New Information: We report inventories of dung beetles from two Amazonian forest reserves in Pará State, Brazil: the Tapajós National Forest and the Carajás National Forest. Surveys were carried out with baited-pitfall traps installed in 2010, 2016, 2017 and 2019. We collected a total of 3,772 individuals from 19 genera and 96 species. We highlight the importance of Amazonian protected areas as refugia for insect biodiversity, particularly dung beetles, which contribute to many key ecosystem processes., (Edrielly C. Carvalho, Maria Eduarda Maldaner, Vinicius Costa-Silva, Heivanice Sehn, Carol Franquini, Vinicius O. Campos, Vinicius P. Seba, Laís F. Maia, Fernando Z. Vaz-de-Mello, Filipe Machado França.)

Aim: This study evaluated the influence of chitosan added to a universal adhesive system used in totaletch (TE) or self-etch (SE) mode on dentin permeability, and on the micromorphology of the adhesive layer., Materials and Method: Dentin discs were obtained from human third molars and randomly distributed according to bonding strategy (TE or SE), and to whether or not 1% chitosan (C) was added to a universal adhesive system (Single Bond Universal/3M ESPE), to create the following groups (n=10): TE, TEC, SE, and SEC. Dentin permeability was measured at baseline and after application of dentin treatments. The surface of the adhesive layer (AL) and the dentin adjacent to the AL were examined under a scanning electron microscope., Results: There were no significant differences in permeability percentage between the groups with and without C (TE and SE versus TEC and SEC) (p>0.05; Mann Whitney test). Dentin permeability was lower when the adhesive system was applied in the SE mode, regardless of the addition of C. The micromorphology of the AL surface showed irregularities, and a greater degree of porosity, when the adhesive system was applied in the SE mode, regardless of chitosan addition. There was a greater depth of penetration of the adhesives into the dentin adjacent to the AL in both the TE and TEC groups. Chitosan added to the adhesive system did not influence dentin permeability., Conclusions: The self-etch strategy led to lower dentin permeability, and to more irregularities on the surface of the adhesive layer., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article., (Sociedad Argentina de Investigación Odontológica.)

Acidic conditions can cause hydrolysis and accelerate degradation of resin composites (RCs). Since there are limited and controversial data on the effect of acids on bulk-fill RCs, this study assessed the surface roughness (SR) and flexural strength (FS) of these RCs under simulated carious and erosion conditions. Bars of Filtek Bulk Fill (FBF, 3M/ESPE), X-tra fil (XTF, Voco), Tetric N-Ceram Bulk Fill (TBF, Ivoclar/Vivadent), and Aura Bulk Fill (ABF, SDI) and a conventional RC [Filtek Z350XT (FZ, 3M/ESPE)] were allocated (n=15) to undergo caries or erosion conditions. The control group was kept in artificial saliva (AS). The bars were evaluated for SR change (final-baseline) and for three-point FS. Data were analyzed using ANOVA and Tukey's test. At the baseline (p <0.001), the SR of RCs ranked as follows: (TBF = XTF) < FBF (none differed from FZ) < ABF. The interplay between RCs and conditions affected SR change (p = 0.025). While after storage in AS, there was no difference among RCs, following carious and erosive conditions, ABF showed higher SR change. For FS (p <0.001), XTF > (FBF = FZ) > (TBF = FZ) > ABF, with no difference among control, carious and erosive conditions (p = 0.148). Depending on the restorative bulk-fill RCs, carious and erosive conditions roughen the surface but do not affect the FS of these materials., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article., (Sociedad Argentina de Investigación Odontológica.)

Melatonin (MLT) is a hormone responsible for regulating several physiological processes. It has been shown that MLT can be an important mediator in bone formation and stimulation, promoting osteoblast differentiation. In clinical practice, in tissue regeneration procedures, it is necessary to use membranes or barriers, associated with biomaterials, or not. The aim of this in vitro study was to assess the effect of melatonin on the activity of osteoblastic cells, associated, or not, with a resorbable collagen membrane (Bio-Gideä). For this, mice-derived pre-osteoblastic cells MC3T3 obtained from the ATCC (American Type Culture Collection) were used. Cultured cells were subject to the following treatments: MLT with a concentration of 1mM, a Bio-Gideä membrane and a membrane associated with MLT (Bio-Gideä + MLT). Proliferation and cell viability assays and protein lysate (ELISA test) quantification for the BMP-2 protein were carried out, in periods of 72 hours, 7 days and 10 days. After analyzing the data (one-way ANOVA, alpha=5%) it was observed that when MLT was used in isolation, there was an increase in cell proliferation and viability in osteoblastic cells (p<0.05). But, when MLT was associated with resorbable membranes, there was an inverse behavior, both in terms of proliferation and viability (p<0.05). In the case of the ELISA test, no secretion of BMP-2 was detected in any of the analyzed groups. It is concluded that MLT has a stimulatory effect on osteoblasts, but, when associated with Bio-Gideä resorbable membranes, it does not show any viable action in osteoblastic cell stimulation., Competing Interests: The authors declare no potential conflicts of interest regarding the research, authorship, and/or publication of this article., (Sociedad Argentina de Investigación Odontológica.)

There is a constant search for bleaching treatments that can offer greater safety with fewer adverse effects, especially in the techniques performed in the office, which usually employ hydrogen peroxide in high concentrations (35% to 40%) that are not recommended by some international control agencies. This in vitro study evaluated the color change after tooth bleaching with the use of ozone and a 10% ozonized carbamide peroxide bleaching treatment for in-office use. Thirty molars were allocated (n = 10): three applications of ozone (1 hour every 3 days); three applications of 10% ozonized carbamide peroxide (1 hour every 3 days); 10% carbamide peroxide agent (8 hours a day for 7 days). The teeth were mounted on a plaster model to simulate the dental arch, and trays made of silicone were used for the application of the bleaching agents and to allow ozone to enter through. The ozone concentration used was 60 μg/mL, with an oxygen flow of 0.25 L/min. The values of color change showed no significant differences among treatments. The variations in the parameters over time, as well as the values of ΔE ab , ΔE 00 , and WI D , showed that there was no significant difference among the three treatments. The use of ozone and 10% ozonized carbamide peroxide for in-office use was effective for tooth bleaching with clinically perceptible and acceptable color alterations. The study was approved on September 10, 2019 by the São Leopoldo Mandic Ethics Research Committee (CAAE No. 17711719.4.0000.5374)., Competing Interests: None

Background: The study aimed to assess the influence of different implant insertion angles and depths on the stresses produced on the surface of peri-implant bone tissue under axial and oblique loading., Material and Methods: The entire study followed the recommendations of the Checklist for Reporting In-vitro Studies (CRIS). The implant was placed in the region of element 36, according to the following models: M1 (0 mm / 0°); M2 (0 mm / 17°); M3 (0 mm / 30°); M4 (2 mm / 0°); M5 (2 mm / 17°); M6 (2 mm / 30°). The models were subjected to loading, with intensity of 100 N. The stress assessment followed the Mohr-Coulomb criterion and qualitative and quantitative analyses were performed., Results: Angled implants and installed below the bone crest produced the highest stresses on the cortical bone, and the axial load presented the highest stress peaks on the buccal side of implants perpendicular to the bone crest. Regardless of the type of load (axial or oblique), inclined implants presented the highest stress peaks on the lingual side of the cortical bone., Conclusions: Implants installed perpendicular to and with a prosthetic platform at bone crest height provided the lowest stresses to peri-implant bone tissue under both axial and oblique loading. Key words: Finite element analysis, dental implants, axial loading, biomechanical phenomena., Competing Interests: Conflicts of interest None., (Copyright: © 2021 Medicina Oral S.L.)

The aim of this study was to compare low- and high-viscosity bulk-fill composites for Knoop microhardness (KHN), microtensile bond strength (MTBS) to dentin in occlusal cavities, and fracture strength (FS) in molars with mesialocclusal- distal restoration. Disk-shaped samples with different thicknesses (2 or 4 mm) of low-viscosity (SDR Flow, Dentsply) and high-viscosity bulk-fill composites (Filtek BulkFill, 3M ESPE; and Tetric-N Ceram Bulk Fill, Ivoclar Vivadent) were prepared for top and bottom KHN analysis (n=10). MTBS to dentin and fracture pattern was evaluated in human molars with occlusal cavities restored with (n=10): conventional nanocomposite (Z350XT, 3M ESPE), low-viscosity (Filtek Bulk-fill Flow, 3M ESPE) or high-viscosity bulk-fill composites (Filtek BulkFill). The FS and fracture pattern of human molar with mesial-occlusal-distal restorations submitted or not to thermomechanical cycling were investigated (n=10) using: intact tooth (control), and restoration based on conventional microhybrid composite (Z250, 3M ESPE), low-viscosity (SDR Flow) or high-viscosity bulk-fill composites (Filtek BulkFill). The data were submitted to split-plot ANOVA (KHN), one-way ANOVA (MTBS), two-way ANOVA (FS) followed by Tukey's test (α=0.05). For KHN, there was no significant difference for the resin composites between the top and bottom. For MTBS, no significant differences among the materials were detected; however, the low-viscosity composite presented lower frequency of adhesive failures. For FS, there was no significant difference between composites and intact tooth regardless of thermomechanical cycling. Low- and high-viscosity bulk-fill composites have comparable microhardness and microtensile bond strength when used in occlusal restorations. Likewise, the bulk-fill composites present similar fracture strength in molars with mesio-occlusal-distal restorations., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article, (Sociedad Argentina de Investigación Odontológica.)

The objective of this work was to evaluate the potential teratogenic and toxic effect of the herbicide 2,4-D (DMA® 806) on bullfrog embryos and tadpoles (Lithobates catesbeianus). We used the FETAX (Frog Embryo Teratogenesis Assay Xenopus) assay for embryos, and for tadpoles, we used acute (96 h) and chronic (49 days) toxicity tests and evaluated aspects of healthiness, hematology, and histopathology. The LC 50-144h (Median Lethal Concentration), EC 50-144h (Median Effective Concentration), MCIG (Minimum Concentration to Inhibit Growth) and TI (Teratogenic Index) for embryos were 792 mg/L, 593 mg/L, 150 mg/L of 2,4-D (DMA) and 1.34, respectively. For tadpoles, the LC 50-96h was 700 mg/L of 2,4-D (DMA) and chronic test indicated an inflammatory process and erythrocytosis (with possible polycythemia), with consequent reduction of the spleen. This demonstrates physiological stress probably due to dehydration, which can be proven by the gill tufts widening intercellular space and gill tuft fusions. We also found injuries to the kidneys and skin of the animals even in the lowest concentration tested. Our results indicated that this pesticide is minimally teratogenic and has a low toxicity on L. catesbeianus embryos and tadpoles, but it can inhibit embryo growth in concentrations lower than those tested in this study. We hypothesized that the herbicide 2,4-D (DMA® 806) may be a respiratory allergen for L. catesbeianus tadpoles and recommend precautionary measures for prolonged exposure of aquatic organisms to this pesticide., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purpose: To conduct a clinical evaluation of calcium lactate and sodium fluoride mouthrinses in reducing sensitivity and efficacy of color change during in-office bleaching., Methods: 75 participants were selected and divided into three groups (n= 25), according to the type of desensitizing treatment tested: calcium lactate mouthrinse prior to sodium fluoride mouthrinse before each bleaching session; daily mouthrinse with sodium fluoride; control (absence of mouthrinse). Each mouthrinse was used for 1 minute. Bleaching was performed following the same protocol in all groups, with 40% hydrogen peroxide (Opalescence Boost), in three 40-minute sessions, with a 48-hour interval between sessions. Clinical parameters such as sensitivity, gingival irritation and mouthrinse acceptability were assessed using Visual Analogue Scale (VAS) and clinical examination at two timepoints: baseline (before any treatment) and 48 hours after the end of treatment. The color was evaluated with a spectrophotometer (VITA Classical scale guide, 3D Master guide and CIEL*a*b*). The data were analyzed by generalized linear models and by one-way ANOVA., Results: There was significant color change in all groups according to the VITA Classical scale guide (P< 0.001). There was no significant difference among the groups for ΔL*, Δa*, Δb* and ΔE over time (P> 0.05). The control group presented a significant increase in sensitivity (P= 0.008). The other groups showed no significant difference between initial and final timepoints (P> 0.05). No symptoms of gingival irritation were observed in any of the groups evaluated. All desensitizing treatments presented high acceptability. Bleaching treatment was effective, regardless of association with desensitizing treatments. No treatment prevented bleaching sensitivity, but the absence of a combined desensitizing treatment led to increased sensitivity., Clinical Significance: Although bleaching sensitivity during in-office bleaching treatment cannot be avoided, daily fluoridated mouthrinse or calcium lactate used prior to fluoridated mouthrinse prevented its increase., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Building trust in science and evidence-based decision-making depends heavily on the credibility of studies and their findings. Researchers employ many different study designs that vary in their risk of bias to evaluate the true effect of interventions or impacts. Here, we empirically quantify, on a large scale, the prevalence of different study designs and the magnitude of bias in their estimates. Randomised designs and controlled observational designs with pre-intervention sampling were used by just 23% of intervention studies in biodiversity conservation, and 36% of intervention studies in social science. We demonstrate, through pairwise within-study comparisons across 49 environmental datasets, that these types of designs usually give less biased estimates than simpler observational designs. We propose a model-based approach to combine study estimates that may suffer from different levels of study design bias, discuss the implications for evidence synthesis, and how to facilitate the use of more credible study designs.

The aim of this in vitro study was to evaluate the effect of bleaching protocols on the surface roughness (Ra), color change and surface micromorphology of a low-viscosity bulk-fill composite (Filtek Bulk Fill Flow, 3M ESPE), a highviscosity bulk-fill composite (Filtek Bulk Fill, 3M ESPE) and a conventional nanoparticulate composite resin (control) (Filtek Z350 XT, 3M ESPE). Forty samples of each composite (disks 5 mm in diameter and 2 mm thick) were randomly divided into four groups (n=10), according to bleaching protocol: a) 10% carbamide peroxide gel (Opalescence, Ultradent Products) (2 h/ day, for 14 days); b) 40% hydrogen peroxide gel (Opalescence Boost, Ultradent Products) (three bleaching sessions, once a week, 45 min/session); c) whitening rinse (Listerine Whitening Extreme, Johnson & Johnson) (2 min/day, for 14 days); and d) distilled water (control). The samples were submitted to triplicate readings (Ra and color [CIELAB parameters]) before and after contact with bleaching protocols. Micromorphology was analyzed in a scanning electron microscope (SEM). Ra and color parameters (ΔL, Δa, Δb and ΔE) were analyzed by generalized linear models (α=0.05). The Ra of the high-viscosity bulk-fill was significantly higher than that of the other composites (p<0.05). Ra increased significantly (p<0.05) and surface became more irregular (SEM analysis) in all the composite resins, regardless of the bleaching protocol (p<0.05). The high-viscosity bulk-fill composite resin group had significantly lower ΔE (p<0.05) than the nanoparticulate composite resin group immersed in distilled water. It was concluded that the characteristics of each resin significantly influenced the Ra more than the bleaching protocol. The high-viscosity bulk-fill resin presented minor color change., Competing Interests: none, (Sociedad Argentina de Investigación Odontológica.)

Purpose: To perform a clinical and radiographic evaluation comparing Filtek Bulk Fill high viscosity bulk-fill resins with Filtek Z350 XT nanoparticulate for 1 year., Methods: 58 restorations were performed for each material (bulk-fill and nanoparticulate), for a total of 116 restorations. Among these, 42 Class I and 16 Class II restorations were performed for each group, in molars and premolars. Clinical evaluation was performed 7 days (baseline), 6 months and 1 year after restorations, using the World Dental Federation (FDI) criteria. Radiographs were obtained at 7 days and 1 year after the restoration was placed and the radiopacity was measured using Image J software at the same time interval., Results: Of the 70 restorations available for evaluation at 1 year, the Mann-Whitney and Friedman tests showed no statistically significant difference for the FDI criteria analyzed. Greater radiopacity was observed for bulk-fill resin compared to nanoparticulate (two-way ANOVA, P= 0.022). This same test showed no difference in radiopacity between the groups in the two evaluation periods (P= 0.062). The high viscosity bulk-fill resin composite presented similar clinical performance to nanoparticulate resin in this evaluation period and higher radiopacity was observed for this material when compared to nanoparticulate resin, in both time periods., Clinical Significance: The high viscosity bulk-fill resin composite showed similar performance to the nanoparticulate resin during the evaluation period of 1 year. Radiopacity showed high values for the bulk-fill resin when compared to nanoparticulate resin. The bulk-fill resin has potential to be used in posterior teeth., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Ecosystem process rates typically increase after plant invasion, but the extent to which this is driven by (i) changes in productivity, (ii) exotic species' traits, or (iii) novel (non-coevolved) biotic interactions has never been quantified. We created communities varying in exotic plant dominance, plant traits, soil biota, and invertebrate herbivores and measured indicators of carbon cycling. Interactions with soil biota and herbivores were the strongest drivers of exotic plant effects, particularly on measures of soil carbon turnover. Moreover, plant traits related to growth and nutrient acquisition explained differences in the ways that exotic plants interacted with novel biota compared with natives. We conclude that novel biological interactions with exotic species are a more important driver of ecosystem transformation than was previously recognized., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Tropical forests and coral reefs host a disproportionately large share of global biodiversity and provide ecosystem functions and services used by millions of people. Yet, ongoing climate change is leading to an increase in frequency and magnitude of extreme climatic events in the tropics, which, in combination with other local human disturbances, is leading to unprecedented negative ecological consequences for tropical forests and coral reefs. Here, we provide an overview of how and where climate extremes are affecting the most biodiverse ecosystems on Earth and summarize how interactions between global, regional and local stressors are affecting tropical forest and coral reef systems through impacts on biodiversity and ecosystem resilience. We also discuss some key challenges and opportunities to promote mitigation and adaptation to a changing climate at local and global scales. This article is part of the theme issue 'Climate change and ecosystems: threats, opportunities and solutions'.

Purpose: To evaluate the effect of a zinc chloride (ZnCl2) solution (2% wt), incorporated into a two-step etch-and-rinse adhesive system (AS), on microtensile bond strength (µTBS) to caries-affected dentin (CAD)., Methods: First, the degree of conversion (DC) of the AS with and without the ZnCl2 solution was evaluated by Fourier transform infrared spectroscopy (FTIR). Second, beam-shaped samples (7 mm × 2 mm × 1 mm) were prepared with the AS containing the ZnCl2 solution to perform flexural strength (FS) tests. For µTBS testing purposes, CAD surfaces were etched with phosphoric acid and randomly divided into three groups (n=10) : ZnCl2- AS with ZnCl2; NT (no treatment)- AS without ZnCl2; and CHX - pretreatment with 2% chlorhexidine solution. AS (Adper Single Bond 2) was applied according to the manufacturer's instructions, and resin composite restorations were built up. After 24 hours, the resin-dentin blocks were sectioned into specimens (0.8 mm2), and then subjected to micro;TBS testing immediately following, or after 6 or 12 months of water storage (WS). The adhesive interface was evaluated by scanning electron microscope. Both µTBS and FS tests were performed using a universal testing machine ( 0.5 mm/minute). FS and DC data were submitted to the Student t-test, and µTBS data were subjected to two-way ANOVA and Tukey's test (α= 0.05)., Results: DC was not affected by ZnCl2 incorporation into AS (P= 0.2527). Higher FS values were obtained in the group with ZnCl2 added to AS. Regarding µTBS, the mean of the NT group was statistically higher than that of the ZnCl2 or the CHX groups (P< 0.001(, regardless of WS, but the latter groups did not differ from each other. µTBS at 24 hours was statistically superior to that of 6 and 12 months of WS (P< 0.001)., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Purpose: To evaluate the influence of ceramic laminate on color stability, surface microhardness, water sorption, and solubility of resin luting agents., Methods: Disk-shaped specimens (10 × 2 mm) of dual-cured resin cements (RelyX ARC or RelyX Ultimate) were obtained, and a light-cured luting agent (RelyX Veneer) was used. In Experiment 1, disk-shaped resin cements (n = 10) were submitted to: I) polymerization with or without ceramic laminate (0.7 mm), and II) immersion in distilled water or coffee, 3 hours daily for 20 days. The surface microhardness loss (%SML) was determined, and the color variables were assessed by the CIE L*a*b* system (ΔE, ΔL*) and the shade guide units (ΔSGU). In Experiment 2, other disk-shaped specimens (n = 5) were submitted to polymerization with or without ceramic laminate to assess their water sorption (WS) and solubility (S). Statistical analysis was performed using 3-way ANOVA and Tukey's test for ΔE, ΔL* and %SML; Mann-Whitney, Kruskal-Wallis, and Dunn's tests for ΔSGU; and 2-way ANOVA and Tukey's test for WS and S. The significance level was set at 5%., Results: No statistically significant differences among the resin cements was observed for %SML, WS, or S, regardless of stain exposure or presence of ceramic laminate during light activation. Coffee caused a significant decrease in ΔL* values. All the resin cements presented visually detectable color alteration for ΔE; however, RelyX Ultimate showed less color change after coffee exposure. RelyX ARC showed the greatest color change in water. RelyX Veneer presented the highest values of ΔSGU, compared with the other resin cements. The WS, S, and %SML of resin cements were not influenced by the staining solution or the presence of ceramic laminate during light activation; however, RelyX Ultimate resin cement presented the best color stability., Clinical Significance: Resin cements can present color changes over time, affecting the long-term esthetic success of laminate ceramic restorations. RelyX Ultimate resin cement presented the best color stability, thus making it a suitable indication for cementing ceramic laminates., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

Formalin is a readily soluble chemical used as a sanitizing agent in the home and hospital. Formaldehyde solutions are routinely used in aquaculture for the prophylaxis and treatment of parasites and fungi, but the adverse effects of their application need to be further investigated. Danio rerio or zebrafish has characteristics favorable to its handling and breeding, and it is highly sensitive to various chemicals, being an ideal experimental model for this type of investigation. Thus, the objective of this study was to verify the toxic and genotoxic effects of formalin and to determine the lethal concentrations of this chemical to support its safe use in disinfection processes. Acute and chronic tests were performed using methods in accordance with international protocols. The genotoxic effect of formalin was evaluated with the micronucleus test using blood samples, which were collected at 96 and 192 h of exposure. The LC 50-96h of formalin in D. rerio was 45.73 mg L -1 , demonstrating its high resistance compared to other species. Regarding the genotoxic effect, the sublethal concentrations of formalin showed a positive correlation with micronuclei according to the increase in its concentration independent of the time of exposure. The incidence of micronuclei increased with concentration, and the addition of 1 mg L -1 formalin corresponded to an increase of 2.9% in the average number of micronuclei. In other words, formalin at even sublethal concentrations caused genotoxic effects in peripheral blood erythrocytes of D. rerio. Therefore, we recommend further studies and other tests involving this chemical for its use at environmentally safe concentrations.

Bisphenol A (BPA) is an emerging contaminant widely used in various industrial products. Sublethal toxicity of BPA on aquatic organisms is expected to occur at a concentration of around 500 μg L -1 , which is much higher than environmentally realistic concentrations found in water bodies (up to 0.41 μg L -1 ). However, there is no information concerning how a BPA contamination gradient could affect the spatial displacement of organisms. We hypothesized that fish might be able to detect an environmentally realistic BPA contamination gradient and avoid potential toxic effects due to continuous exposure. Therefore, the objectives of this work were: (i) to determine if BPA could trigger an avoidance response in the freshwater fish Poecilia reticulata; (ii) to assess whether BPA-driven avoidance occurs at environmentally relevant concentrations; and (iii) to estimate the population immediate decline (PID) at the local scale, considering avoidance and mortality as endpoints. Avoidance experiments were performed in a seven-compartment non-forced exposure system, in which a BPA contamination gradient was simulated. The results indicated that BPA triggered avoidance in P. reticulata. In a traditional forced acute toxicity test, lethal effects in 50% of the population occurred at a BPA concentration of 1660 μg L -1 , while in the non-forced system with a BPA concentration gradient, avoidance of 50% of the population occurred at a concentration four orders of magnitude lower (0.20 μg L -1 ). At environmentally relevant BPA concentrations, PID was mainly determined by the avoidance response. Avoidance in P. reticulata populations is expected to occur at BPA concentrations below those that cause sublethal effects on fish and are considered safe by international agencies (≤1 μg L -1 ). The approach used in the present study represents a valuable tool for use in environmental risk assessment strategies, providing a novel and ecologically relevant response that is complementary to traditional ecotoxicological tests., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Purpose: To measure the microgap between dental implants and custom abutments fabricated using different computer-aided design/computer-aided manufacture (CAD/CAM) methods before and after mechanical cycling., Materials and Methods: CAD software (Dental System, 3Shape) was used to design a custom abutment for a single-unit, screw-retained crown compatible with a 4.1-mm external hexagon dental implant. The resulting stereolithography file was sent for manufacturing using four CAD/CAM methods (n = 40): milling and sintering of zirconium dioxide (ZO group), cobalt-chromium (Co-Cr) sintered via selective laser melting (SLM group), fully sintered machined Co-Cr alloy (MM group), and machined and sintered agglutinated Co-Cr alloy powder (AM group). Prefabricated titanium abutments (TI group) were used as controls. Each abutment was placed on a dental implant measuring 4.1× 11 mm (SA411, SIN) inserted into an aluminum block. Measurements were taken using scanning electron microscopy (SEM) (×4,000) on four regions of the implant-abutment interface (IAI) and at a relative distance of 90 degrees from each other. The specimens were mechanically aged (1 million cycles, 2 Hz, 100 N, 37°C) and the IAI width was measured again using the same approach. Data were analyzed using two-way analysis of variance, followed by the Tukey test., Results: After mechanical cycling, the best adaptation results were obtained from the TI (2.29 ± 1.13 μm), AM (3.58 ± 1.80 μm), and MM (1.89 ± 0.98 μm) groups. A significantly worse adaptation outcome was observed for the SLM (18.40 ± 20.78 μm) and ZO (10.42 ± 0.80 μm) groups. Mechanical cycling had a marked effect only on the AM specimens, which significantly increased the microgap at the IAI., Conclusion: Custom abutments fabricated using fully sintered machined Co-Cr alloy and machined and sintered agglutinated Co-Cr alloy powder demonstrated the best adaptation results at the IAI, similar to those obtained with commercial prefabricated titanium abutments after mechanical cycling. The adaptation of custom abutments made by means of SLM or milling and sintering of zirconium dioxide were worse both before and after mechanical cycling.

Objective: This study evaluated the effectiveness of toothbrushing with whitening toothpaste in altering the shade of stained human enamel., Materials and Methods: Thirty fragments of human enamel, stained with chlorhexidine/black tea underwent 1000 and 5000 brushing cycles (BC) with ( n = 10): PLS (Gel Dental Day, Bitufo), Close Up White Now, Unilever (COVB) and regular (Gel Dental Night, Bitufo) toothpaste. Images were taken before staining (baseline), after staining (STN) and following 1000 and 5000 BC and were analyzed using the CIELAB parameters (ΔE, Δb and ΔL)., Statistical Analysis Used: Data were submitted to two-way ANOVA (α = 0.05)., Results: ΔE was higher from STN to baseline; 1000 BC to STN and 5000 BC to STN ( P < 0.001). Significant differences in Δb values were found from 1000 BC to STN and 5000 BC to STN. For COVB, greater ΔL was observed from 1000 BC to STN, what differed statistically from the regular toothpaste ( P < 0.05). There was no difference between toothpaste when ΔL was calculated from 5000 CB to STN., Conclusions: Toothpaste containing COVB or PLS in association with 5000 BCs showed similar effectiveness in changing enamel shade; but after the first 1000 toothbrushing cycles, the use of COVB toothpaste promoted higher lightness in stained enamel., Competing Interests: There are no conflicts of interest.

The purpose of this study was to evaluate the effects of steam autoclave sterilization on the tensile strength of two types of resin cements used to bond customized CAD/CAM zirconia abutments onto titanium bases. Forty sets of zirconia abutments cemented to screwed titanium bases of implants analogs were divided into 4 groups (n = 10). Two groups were treated with a conventional chemically activated resin cement (ML, Multilink Ivoclar Vivadent) and the other two groups with a self-adhesive dual resin cement (RelyX U200, 3M ESPE). One group from each cement was submitted to steam autoclaving. The autoclave sterilization cycle was performed after 72 hours of cementation for 15 minutes at 121°C and 2.1 Kgf/cm 2 . The samples were subjected to tensile strength testing in a universal testing machine (200 Kgf, 0.5 mm/min), from which the means and standard deviations were obtained in Newtons. Results showed (via ANOVA and Tukey's test; α = 0.05) that in the absence of steam autoclaving, no difference was observed in tensile strength between the cements tested: ML: 344.87 (93.79) and U200: 280 (92.42) (P = .314). Steam autoclaving, however, significantly increased tensile strength for the ML: 465.42 (87.87) compared to U200: 289.10 (49.02) (P < .001). Despite the significant increase in the ML samples (P = .013), autoclaving did not affect the tensile strength of the U200 samples (P > 0.05). The authors concluded that steam autoclaving increases the mean tensile strength of the chemically activated cement compared to the dual-cure self-adhesive cement. The performance of both cements evaluated was similar if the sterilization step was disconsidered.

The aims of this study were to evaluate the effectiveness of different microwave radiation regimens for disinfection of type IV dental stone surfaces and to assess the influence of these regimens on surface roughness and dimensional change following disinfection. Three hundred cylindrical (20 × 2-mm) test specimens were made in type IV stone and divided into subgroups of 20 according to the microorganisms tested (Staphylococcus aureus, Escherichia coli, or Candida albicans) and the 900-W microwave radiation protocol (cycles of 3, 5, or 7 minutes; a positive control; or a negative control). To test physical changes, 80 test specimens were made with the same dimensions except that they had 2 parallel and symmetrical indentations measuring 8 × 4 mm. These specimens were divided into 4 subgroups of 20 each (a subgroup for each radiation time and a negative control). The mean dimensional change and roughness data were analyzed by mixed models for repeated measures and Tukey-Kramer tests. Disinfection was analyzed with descriptive statistics. For E coli and C albicans, all radiation times proved effective at sterilizing the test specimens. For S aureus, sterilization was achieved with 5 and 7 minutes of exposure; however, colonies were observed in 10 Petri dishes (50%) exposed to 3 minutes of microwave radiation. No statistically significant difference in dimensional change or surface roughness was observed for any radiation regimen (P > 0.05).

Background: The aim of this study was to evaluate a new technique for treating dehiscence buccal bone sites (Class II) with immediate implant and collagen-enriched bovine-derived xenograft blocks without a surgical flap or membrane., Methods: Individuals with at least 5 mm of buccal bone dehiscence were selected for a flapless surgical approach to insert xenograft blocks into buccal dehiscence defects as well as the gap between implant and residual bone wall. No membrane was used. Buccal bone wall height was measured by computed tomography in the preoperative period (T0) and 6 to 12 months after procedure (T1). Likewise, buccal-lingual width of alveolar ridge as well as thickness of buccal wall was compared with the contralateral tooth., Results: Fourteen patients were selected. Buccal wall height at T1 was not significantly different after 6 to 12 months between the treated and contralateral teeth, although both were greater than T0 (P <0.01). The heights ranged from 6.4 to 16.30 mm at T0, 12.8 to 25.6 mm at T1, and 14.8 to 25.29 mm in the contralateral teeth. Significant differences were observed between treated teeth (T1) and their contralateral, both buccal-lingually in the alveolar ridge (P = 0.007) and in buccal wall thickness (P = 0.003). Wall thickness ranged from 0.9 mm to 3.81 mm at T1 and 0.25 mm to 1.60 mm in the contralateral teeth., Conclusion: Immediate implant placement at dehiscence buccal bone sites using flapless surgery combined with xenograft blocks provided complete formation of the buccal bone wall up to the implant shoulder.

The aim of this study was to investigate the antimicrobial effect of an experimental adhesive system containing chitosan (0.2% and 0.5%) against Streptococcus mutans and Lactobacillus casei. Twenty-four extracted human third molars were used, and 4 cavities were prepared in each tooth. The teeth were contaminated with either S mutans (n = 12 teeth, 48 cavities) or L casei (n = 12 teeth, 48 cavities) microorganisms. One cavity in each tooth received 1 of the following treatments: negative control (no treatment [NC]), positive control (Adper Single Bond 2 [SB]), an experimental adhesive containing chitosan 0.2% (CHI2), or an experimental adhesive containing chitosan 0.5% (CHI5). After sealing of the cavities and an incubation period, dentin scrapings were collected from each cavity for microbiological evaluation. Analysis of variance and Tukey tests revealed no statistically significant differences among the SB, CHI2, and CHI5 groups (P > 0.05), but all 3 differed significantly from the NC group (P ≤ 0.05). The concentrations of chitosan did not influence the antimicrobial effect against S mutans and L casei, presenting a similar effect to that of a conventional 2-step adhesive system.

Objective: This study evaluated the antimicrobial effect of papain-based gel (Papacárie/ P) followed by self-etching adhesive systems with MDPB monomer (Clearfil Protect Bond/ PB) and without (Clearfil SE Bond/ Cl) on Streptococcus mutans (Sm) and Lactobacillus casei (Lc)., Study Design: The dentin of twenty human teeth was exposed to prepare four cylindrical cavities in each tooth. The cavities were incubated with Sm or Lc. One cavity from each tooth served as contamination control (positive control group); the other three were treated with P, P+CL and P+PB. The cavities were sealed and after 72 h, dentin samples were collected and microbial cultivation was performed. Microbial count was undertaken (CFUs/mg) according to the morphological characteristics for Sm and Lc. Analysis of variance and Tukey's test were applied (α=5%)., Results: For Sm, groups P+Cl and P+PB had lower microbial count than group P (no statistical differences between P+Cl and P+PB). For Lc, group P+Cl had microbial count similar to group P. There was statistical difference between cavities treated with P and P+PB but none between groups P+Cl and P+PB. After using P, both self-etching adhesives showed antimicrobial potential, although Clearfil Protect Bond proved better against Lc., Conclusions: Both self-etching adhesives used after application of Papacárie showed antimicrobial potential, although Clearfil Protect Bond proved more effective against Lactobacillus casei.

Purpose: To evaluate in vitro, the efficacy of gutta-percha (GP) and polytetrafluoroethylene (PTFE) tape to act as a seal against the penetration of Escherichia coli through prosthetic implant abutments (PIA) with external hexagon (EH) and morse taper (MT) connections., Materials and Methods: 120 sets of implant analogs with their respective PIA were used. 60 sets from each system were divided into four groups (n = 15): I - GP sealing; II - PTFE tape sealing; III - no sealing (NS) and IV - negative control. Microbiological challenge was performed by placing bacterial colonies inside the titanium PIA before screwing them into their respective analogs. Each set was immersed in 5 mL of BHI and incubated for 14 days with daily checks for contamination, according to the nutrient medium turbidity., Results: The type of seal used influenced microbial penetration at all evaluation times (p < 0.05). Compared to GP, PTFE led to an increase in turbidity and its effectiveness against microbial penetration was equivalent to group NS. When the sealing efficacy of each group was compared in terms of time, Cochran's Q test revealed that in the two groups sealed with PTFE, there was a progressive increase in the number of turbid nutrient media (p < 0.0001), while in the group sealed with GP, this was only observed in the MT system (p = 0.0310)., Conclusions: Sealing the PIA channel with GP was a significantly superior approach to sealing it with PTFE tape. PTFE tape or NS led to a progressive increase in microbiological leakage over time in PIA channels, however, this only occurred with GP in the MT system., (© 2015 Wiley Periodicals, Inc.)