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Geotextiles made from plant fibers creates a suitable environment for plant growth as part of soil bioengineering techniques. The faster decomposition of plant fiber geotextiles compared to synthetic ones demands the use of composites that enhance their waterproofing and extend their durability in the environment. The objective of this work was to evaluate the resistance of a geotextile made with Thypha domingensis to degradation caused by climatic variables. Tensile strength tests were conducted in the laboratory in order to evaluate the degradation of geotextiles treated with single and double layers of waterproofing resin. Based on Scanning Electron Microscopy (SEM) images, it was verified that applying double layer of waterproofing resin delays the fibers degradation up to 120 days of exposure to the effects of climatic variables other than temperature. The maximum resistance losses due to the geotextile's exposure to degradation were statistically significant for all three treatments: control-without waterproofing resin, with one layer resin, and with two layers resin. Therefore, waterproofing resin, provides a long-term protective solution for geotextiles made from cattail fibers.

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Aim: The tensile strength and modulus of elasticity of gutta-percha cones can be chemically altered due to disinfectant solutions. Therefore, the aim of the present study was to compare tensile strength and elastic modulus of gutta-percha cones subjected to sodium hypochlorite (NaOCl) disinfection at different times. Materials and Methods: This in vitro and longitudinal experimental study consisted of 45 gutta-percha cones, divided equally into three groups: Group 1 (disinfection with 2.5% NaOCl), Group 2 (disinfection with 5.25% NaOCl), and control group. All groups were subdivided according to immersion times for 1, 5, and 10 minutes. Tensile strength and elastic modulus were measured with a universal testing machine. For comparing more than two independent groups, parametric analysis of variance test with Sheffe's post hoc was used and for multivariate analysis, and multivariate analysis of variance test based on Pillai's Trace was used. In all statistical analysis, a significance level P ≤ 0.05 was considered. Results: When comparing the tensile strength of gutta-percha cones, no significant differences were observed after being immersed at 1, 5, and 10 minutes in NaOCl 2.5% (P = 0.715) and 5.25% (P = 0.585). Regarding the elastic modulus, a significant decrease (P < 0.05) was observed in those that were immersed in NaOCl 2.5% and 5.25% for 1, 5, and 10 minutes. Furthermore, increased NaOCl concentration significantly reduced the elastic modulus (P < 0.001). However, there were no significant differences in tensile strength (P > 0.05) and elastic modulus (P > 0.05), when evaluating the interaction between NaOCl concentration and time. Conclusion: Increasing NaOCl concentration significantly reduced the modulus of elasticity without affecting the tensile strength of gutta-percha cones, regardless of immersion time. Furthermore, the interaction of time and NaOCl concentration did not significantly affect the tensile strength and elastic modulus.

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OBJECTIVE: This study aims to evaluate the effects of exposure time and irradiance on the dentin bonding properties (microtensile bond strength (µTBS) and nanoleakage (NL)) of the Clearfil Universal Bond Quick (CUQ) adhesive and Scotchbond Universal Adhesive (SBU) immediately and after 2 years of water storage. MATERIAL AND METHODS: Hence, 128 human molars were randomly assigned to 16 groups based on adhesive strategy, irradiance/exposure times, and storage time for each universal adhesive tested. The adhesives were applied using the etch-and-rinse and self-etch strategies and were light-cured using four different irradiance/exposure times: 1400 mW/cm2 for 5 s (1400 × 5), 1400 mW/cm2 for 10 s (1400 × 10), 3200 mW/cm2 for 5 s (3200 × 5), and 3200 mW/cm2 for 10 s (3200 × 10). Then, each sample was restored and sectioned into a resin-dentin bonded stick to be tested for µTBS and NL (immediately and after 2 years of water storage). The mean µTBS and NL of all resin-dentin bonded sticks from the same hemi-tooth (factor time) were statistically analyzed using a three-way ANOVA and Tukey's test (a = 0.05). RESULTS: Despite a significant decrease in the µTBS values for all groups after 2 years of water storage, the 3200 × 5 group showed higher µTBS values, whereas the 3200 × 10 group showed lower µTBS values for both universal adhesives tested. Although a significant increase in the NL values was observed for all groups after 2 years of water storage, the 3200 × 10 group showed higher NL values than the other groups (p < 0.001). CONCLUSION: Results indicate that light-curing the adhesive layer with 14-16 J/cm2 led to an improvement in the stability of the resin-dentin adhesive interface. A longer exposure time (10 s) coupled with a higher irradiance (3200 mW/cm2) resulted in a greater degree of degradation of the adhesive interface. CLINICAL SIGNIFICANCE: To guarantee better stability of the adhesive interface, clinicians could be preferred a light-cured universal adhesive layer with 14-16 J/cm2. Higher irradiances should be avoided.

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The failure of ligament reconstruction has different risk factors, among which we can highlight the period before its incorporation, which is a mechanically vulnerable period. Loss of resistance over time is a characteristic of living tissues. Dissection with bone insertions of the cruciate ligaments of animal models is not described; however, it is essential for monoaxial assays to extract information from tests such as relaxation. The present work describes the dissection used for the generation of a test body for the performance of nondestructive tests to evaluate the mechanical behavior. We performed dissection of four porcino knee ligaments, proposing a dissection technique for the cruciate ligaments with bone inserts for comparison with collateral ligaments. The ligaments were submitted to relaxation tests and had strain gauges placed during the tests. The results showed viscoelastic behavior, validated by strain gauges and with a loss over time; with some ligaments presenting with losses of up to 20%, a factor to be considered in future studies. The present work dissected the four main ligaments of the knee demonstrating the posterior approach that allows maintaining their bone insertions and described the fixation for the monotonic uniaxial trials, besides being able to extract the viscoelastic behavior of the four ligaments of the knee, within the physiological limits of the knee.

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Biodegradable polymers have been strongly recognized as an alternative to replace traditional petrochemical plastics, which have become a global problem due to their long persistence in the environment. In this work, the effect of the addition of titanium dioxide nanoparticles (TiO2NP) on the morphology, physicochemical properties and biodegradation under industrial composting conditions of cassava starch-based nanocomposites obtained by extrusion at different screw speeds (80 and 120 rpm) were investigated. Films performed at 120 rpm (S120 and S120-TiO2NP) showed completely processed starch and homogeneously distributed nanoparticles, leading to much more flexible nanocomposites than those obtained at 80 rpm. The incorporation of TiO2NP led to an increase in storage modulus of all films and, in the case of S120-TiO2NP, to higher strain at break values. From the Kohlrausch-Williams-Watts theoretical model (KWW), an increase in the relaxation time of the nanocomposites was observed due to a decrease in the number of polymer chains involved in the relaxation process. Additionally, S120-TiO2NP showed effective protection against UV light, greater hydrophobicity and faster biodegradation in compost, resulting in a promising material for food packaging applications.

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This study evaluated the influence of the TiO2 nanoparticles (NPs) on the mechanical and chemical performance of Sn and Sn-Ag alloys. The XRD (X-ray diffraction) and HR-TEM (high resolution-transmission electron microscopy) methods were used to characterize the NPs synthesized by the sol-gel microwave process. The chemical composition of the alloys was Sn, Sn+3TiO2 NPs, Sn-5Ag+1.5TiO2 NPs, Sn-10Ag, and Sn-10Ag+3TiO2 NPs, obtained from an experimental factorial design (EFD). A statistical model was used to determine the mechanical and chemical properties, showing the Vickers hardness response surface, tensile strength, wear, and corrosion resistance. The wear and corrosion tests for the various alloy compositions were performed using human artificial saliva solution. The results indicated that the Sn-10Ag+3TiO2 NPs exhibited the highest mechanical performance due to their increased hardness (380 HV), tensile strength (370 N), and wear resistance (0.34 × 10-3 mm3 Nm-1); in all the cases, the inclusion of TiO2 NPs enhanced the corrosion resistance of the alloys. According to the American Dental Association (ADA), Sn-10Ag+3TiO2 NPs alloy could be classified as a possible type IV restorative material.

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Abstract The failure of ligament reconstruction has different risk factors, among which we can highlight the period before its incorporation, which is a mechanically vulnerable period. Loss of resistance over time is a characteristic of living tissues. Dissection with bone insertions of the cruciate ligaments of animal models is not described; however, it is essential for monoaxial assays to extract information from tests such as relaxation. The present work describes the dissection used for the generation of a test body for the performance of nondestructive tests to evaluate the mechanical behavior. We performed dissection of four porcino knee ligaments, proposing a dissection technique for the cruciate ligaments with bone inserts for comparison with collateral ligaments. The ligaments were submitted to relaxation tests and had strain gauges placed during the tests. The results showed viscoelastic behavior, validated by strain gauges and with a loss over time; with some ligaments presenting with losses of up to 20%, a factor to be considered in future studies. The present work dissected the four main ligaments of the knee demonstrating the posterior approach that allows maintaining their bone insertions and described the fixation for the monotonic uniaxial trials, besides being able to extract the viscoelastic behavior of the four ligaments of the knee, within the physiological limits of the knee.

Resumo A falha da reconstrução ligamentar tem diferentes fatores de risco, dentre os quais podemos destacar o período antes da sua incorporação, o qual configura um período mecânico vulnerável. A perda de resistência ao longo do tempo é uma característica dos tecidos vivos. A dissecção com as inserções ósseas dos ligamentos cruzados de modelos animais não é descrita; todavia, para os ensaios monoaxiais, é fundamental extrair as informações de ensaios como os de relaxação. O presente trabalho realiza a descrição da dissecção utilizada para a geração de corpo de prova para a realização de ensaios não destrutivos para avaliar o comportamento mecânico. Realizamos dissecção de quatro ligamentos de joelho porcino, propondo uma técnica de dissecção para os ligamentos cruzados com as inserções ósseas para comparação com os colaterais. Os ligamentos foram submetidos a testes de relaxação e foram colocadas strain gauges durante os testes. Os resultados mostraram comportamento viscoelástico, validado pelas strain gauges e com uma perda ao longo do tempo, sendo que, em alguns ligamentos, as perdas chegaram a até 20%, fator este a ser considerado em trabalhos futuros. O presente trabalho dissecou os quatro principais ligamentos do joelho, demonstrando a abordagem posterior que permite manter as suas inserções ósseas e descrevendo a fixação para os ensaios uniaxiais monotônicos, além de ter conseguido extrair o comportamento viscoelástico dos quatro ligamentos do joelho dentro dos limites fisiológicos do joelho.

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Objective: To evaluate the microtensile bond strength in different dentine conditions (etched-E, non-etched-N, dry-D and wet-W) of a multimode adhesive (Scotchbond Universal-SU, 3M/ESPE) and a total etching adhesive (Ambar-AB, FGM) using a sonic device (Smart Sonic Device-SD, FGM). Material and methods: In this in vitro study, ninety six sound extracted human molars were divided into 12 groups (n=8) according to different dentine conditions and adhesive systems. Enamel was removed and the middle dentine surfaces were polished. Each adhesive system was applied according to the different dentine conditions, and composite resin blocks were incrementally built up and stored for 24 hours. Specimens were sectioned into sticks and bond strength data were analyzed with the Kruskal-Wallis test and Mann-Whitney U tests. Results: No effects of sonic application and were observed. In general, AB showed lower results compared to the SU. E and N conditions did not statistically affect the bond strength of SU groups. Dry dentine presented statistically superior bond strength values when compared to wet dentine for SU/E/SD group. Conclusion: Adhesion of dry dentine with multimode adhesive system may be superior to wet dentine with sonic application. The modes of application had no influence in bond strength of studied adhesives.

Objetivo: Evaluar la resistencia de la unión microtensil en diferentes condiciones de dentina (grabado-E, sin grabado-N, seco-D y húmedo-W) de un adhesivo multimodo (Scotchbond Universal-SU, 3M/ESPE) y un adhesivo de grabado total (Ambar-AB, FGM) utilizando un dispositivo sónico (Smart Sonic Device-SD, FGM). Material y Métodos: En este estudio in vitro, noventa y seis molares humanos extraídos sanos se dividieron en 12 grupos (n=8) de acuerdo con diferentes condiciones de dentina y sistemas adhesivos. Se eliminó el esmalte y se pulieron las superficies centrales de la dentina. Cada sistema adhesivo se aplicó de acuerdo con las diferentes condiciones de dentina, y los bloques de resina compuesta se acumularon de forma incremental y se almacenaron durante 24h. Las muestras se seccionaron en barras y los datos de resistencia de la unión se analizaron con la prueba de Kruskal-Wallis y la prueba de U de Mann-Whitney. Resultado: No se observaron efectos de la aplicación sónica. En general, AB mostró resultados más bajos en comparación con el SU. Las condiciones E y N no afectaron estadísticamente la fuerza de unión de los grupos SU. La dentina seca presentó valores de fuerza de adhesión estadísticamente superiores en comparación con la dentina húmeda para el grupo SU/E/SD. Conclusión: La adhesión de la dentina seca con un sistema adhesivo multimodo puede ser superior a la dentina húmeda con aplicación sónica. Los modos de aplicación no tuvieron influencia en la resistencia de la unión de los adhesivos estudiados.

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Poliéter-éter-cetona (Polyetheretherketone - PEEK) é um polímero de excelentes propriedades mecânicas, o que o torna um potencial candidato para substituir ligas metálicas em diversas especialidades odontológicas. Quando utilizado como infraestrutura para confecção de próteses odontológicas, a adesão do PEEK ao material de revestimento estético é determinante para a longevidade do tratamento, embora a baixa energia de superfície e grande estabilidade química do polímero tornem essa adesão um desafio a ser superado. Objetivo: Responder à pergunta: "Outros tratamentos de superfície do PEEK geram resistências de união superiores ao adesivo comercial?" Métodos: A busca foi feita nas bases Pubmed, , LILACS, Scopus, Web of Science, EMBASE, ProQuest e Google Scholar em junho de 2023 e não houve restrição relativa ao idioma ou à data de publicação dos estudos. Foram utilizados os seguintes termos e operadores booleanos: "polyether ether ketone" [MH] OR "polyether ether ketone" OR "polyetheretherketone" OR "polyetherketoneketone" OR "PEEK" AND "shear strength" [MH] OR "shear strength" OR "shear bond strength" OR "tensile bond strength" OR "shear" OR "tensile" OR "microtensile" OR "microshear" OR "bonding" OR "bond strength" OR "microtensile strength" OR "microshear bond strength" OR "bond" OR "adhesion" OR "bond integrity" OR "bonded" OR "Bonding Strength" OR "Bonding Behavior" OR "Adhesive Performance" OR " surface bonding" OR "tensile strength" [MH] OR "tensile strength". Foram incluídos exclusivamente estudos in vitro. Resinas compostas e resinas acrílicas foram consideradas como materiais de revestimento para PEEK. A média e o desvio padrão expressos em MPa e obtidos a partir de testes de cisalhamento e tração foram utilizados para relatar a resistência de união entre o PEEK e os materiais de revestimento. As meta-análises foram realizadas e a ferramenta Cochrane Collaboration avaliou o risco de viés (RoBDEMAT). Resultados: Foram selecionados 23 estudos. A resistência de união entre PEEK e resina composta foi favorecida pelo uso do adesivo (P<0,00001), independentemente do tipo de adesivo. O pré-tratamento com jato de areia Al2O3 (P<0,00001), ácido sulfúrico (P<0,00001), plasma frio (P=0,0006) e laser (P<0,00001) mostrou-se eficiente, embora o condicionamento com solução piranha não tenha tido efeito estatisticamente significativo (P=0,47). Conclusão: A aplicação de ácido sulfúrico antes do adesivo apresentou melhores resultados de resistência de união em comparação ao uso isolado do adesivo.

Polyether-ether-ketone (Polyetheretherketone - PEEK) is a polymer with excellent mechanical properties, which makes it a potential candidate to replace metallic alloys in several dental specialties. When used as an infrastructure for the manufacture of dental prostheses, the adhesion of PEEK to the aesthetic coating material is decisive for the longevity of the treatment, although the low surface energy and great chemical stability of the polymer make this adhesion a challenge to be overcome. Objective: Answer the question: "Do other PEEK surface treatments generate bond strengths superior to commercial adhesive?" Methods: The search was carried out in the Pubmed, LILACS, Scopus, Web of Science, and EMBASE, ProQuest and Google Scholar databases in June 2023 and there were no restrictions regarding the language or publication date of the studies. The following terms and bolean operators were used: "polyether ether ketone" [MH] OR "polyether ether ketone" OR "polyetheretherketone" OR "polyetherketoneketone" OR "PEEK" AND "shear strength" [MH] OR "shear strength" OR " shear bond strength" OR "tensile bond strength" OR "shear" OR "tensile" OR "microtensile" OR "microshear" OR "bonding" OR "bond strength" OR "microtensile strength" OR "microshear bond strength" OR "bond" OR "adhesion" OR "bond integrity" OR "bonded" OR "Bonding Strength" OR "Bonding Behavior" OR "Adhesive Performance" OR "surface bonding" OR "tensile strength" [MH] OR "tensile strength". Only in vitro studies were included. Composite resins and acrylic resins were considered as coating materials for PEEK. The mean and standard deviation expressed in MPa and obtained from shear and tensile tests were used to report the bond strength between PEEK and coating materials. Meta-analyses were performed and the Cochrane Collaboration tool assessed the risk of bias (RoBDEMAT). Results: 23 studies were selected. The bond strength between PEEK and composite resin was favored by the use of the adhesive (P<0,00001), regardless of the type of adhesive. Pretreatment with Al2O3 sandblasting (P<0,00001), sulfuric acid (P<0,00001), cold plasma (P=0,0006) and laser (P<0,00001) proved to be efficient, although conditioning with piranha solution did not have a statistically significant effect (P=0,47). Conclusion: The application of sulfuric acid before the adhesive showed better results in bond strength compared to the use of the adhesive alone.

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Aim: The purpose of this study was to investigate the biofilm effect on the hybrid ceramic-resin cement bond strength (BS) by comparing two methods. Methods: Teeth were distributed into groups (n=5), according to the resin cement (Maxcem Elite-(MC) or NX3 Nexus-(NX)) and degradation method (24h or 7 days in distilled water; 7 or 30 days incubated with biofilm and 30 days in sterile media). Treated surfaces of Vita Enamic blocks (5x6x7mm) were luted to treated or no treated dentin surfaces and light-cured. After 24h, beams were obtained (1x1x10mm) and stored accordingly. The flexural bond strength (FBS) was assessed by four-point bending test. Additional beams were obtained from new teeth (n=5), stored for 24h or 7 days in distilled water, and submitted to a microtensile bond strength (µTBS) assay. Failure modes were determined by scanning electron microscopy (100X). The flexure strength of the cements (n=10) was assessed by a four-point bending test. Data were analyzed by 1 and 2-ways ANOVA, and Tukey's test (α=0.05). Results: There was no significant difference between the degradation methods for the FBS groups. For the µTBS, the significant difference was as follows: NX 7days > NX 24h > MC 7days = MC 24h. Failure mode was mainly adhesive and mixed, but with an increase of cohesive within cement and pre-failures for the MC groups assessed by µTBS. NX had better performance than MC, regardless of the method. Conclusions: The biofilm had no effect on the materials BS and FBS test was a useful method to evaluate BS of materials with poor performance

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Aim: Evaluating the resin-dentin bond strength of Class II conventional and bulk-fill composite restorations, using different cavity sizes before and after aging. Methods: Seventy-five human molars were distributed into groups according to the buccolingual width of the cavities, conservative (n=25) and extended (n=50). They were divided according to the restorative material: conventional (Z100/control group) or bulk-fill resin composites (Filtek Bulk Fill/FBF; Tetric N Ceram Bulk Fill/TNCBF; Filtek Bulk Fill Flow/FBFF; Surefill SDR flow/SDR). The restored teeth were sectioned on sticks (n=50 per restorative materials + width cavities group), half were stored in Water/Ethanol 75% for 30 days and the other half were submitted to the immediate microtensile bond strength (µTBS) test. Data were analyzed applying the Three-Way Analysis of Variance (ANOVA), Bonferroni test, test t, and Weibull analyses (p<0.05). Results: SDR and FBF presented lower µTBSvalues for extended preparation when compared to the conservative preparation, before aging. After aging, only for the FBFF, a decrease in the µTBSvalues was observed. Comparing the µTBSvalues, before and after aging, the SDR demonstrated lower µTBSvalues after aging when the conservative cavity was used. A decrease in the µTBSvalues was observed for the Z100, the FBF and, the FBFF, after aging, when the extended cavity was used. Conclusion: The effect of cavity preparation and aging on the resin-dentin of Class II is material dependent. Most of the bulk-fill resin composites evaluated presented a similar performance to the conventional resin composites for all the conditions of this study

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Dental implants could give back function, esthetics and quality of life to patients. The correct choice of the implant, especially in borderline cases, is essential for a satisfactory result. Aim: Thus, the objective of this study was to evaluate the mechanical behavior of Morse taper implants with two different prosthetic interfaces. Methods: Twenty self-locking Morse taper implants, 2.9 mm in diameter (FAC), and 20 Morse taper implants, 3.5 mm in diameter (CM) were divided into two groups (n=10), and submitted to strength to failure test, optical microscopic evaluation of fracture, metallographic analysis of the alloy, finite element analysis (FEA) and strain gauge test. A Student's t test (α = 0.05) was made for a statistical analysis. Results: For the strength to failure test, a statistically difference was observed (p <0.001) between FAC (225.0 ± 19.8 N) and CM (397.3 ± 12.5 N). The optical microscopic evaluation demonstrated a fracture pattern that corroborated with FEA ́s results. The metallographic analysis determined that the implants of the FAC group have titanium-aluminum-vanadium alloy in their composition. In the strain gauge test, there was no statistical difference (p = 0.833) between CM (1064.8 ± 575.04 µS) and FAC (1002.2 ± 657.6 µS) groups. Conclusion: Based on the results obtained in this study, ultra-narrow implants (FAC) should ideally be restricted to areas with low masticatory effort

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Introducción: la cerámica de disilicato de litio es una excelente opción en rehabilitación, confeccionado con la técnica de inyección o maquinadas. El objetivo de este estudio fue evaluar la influencia de dos sistemas adhesivos sobre los valores de resistencia de unión en cerámicas de disilicato de litio inyectado y maquinado. Métodos: se utilizó discos de disilicato de litio, IPS e. Max CAD (Ivoclar Vivadent, Liechtenstein, Swiss), de 10mm de diámetro y 1mm de espesor embebidos en tubos de PVC. Se distribuyó en 4 grupos de trabajo, 2 en cerámica de litio inyectadas y 2 en maquinada, se aplicaron los adhesivos Palfique Bond y Tetric N-bond Universal según la distribución de grupos, luego se fotopolimerizó durante 10 segundos con lámpara luz led, se colocaron los tubos Tygon® para el relleno con resina fluida; una vez retirado los tubos Tygon®, se llevaron las muestras a una máquina de ensayo universal donde se realizó la prueba de micro cizallamiento. Resultados: los valores de resistencia de unión más significativos fueron encontrados en las cerámicas de disilicato de litio adherida con el adhesivo Palfique Bond y Tetric Bond teniendo una diferencia significativa (p= 0.001), los valores de resistencia de unión del adhesivo Palfique Bond y Tetric Bond en cerámica inyectada no tuvieron diferencia significativa. Conclusión: las cerámicas de disilicato de litio maquinadas presentan mejores valores de resistencia de unión al micro cizallamiento.

Introduction: lithium disilicate ceramics are an excellent choice in rehabilitation, made with the technique of injection or machining. The aim of this study was to evaluate the influence of two adhesive systems on the values of binding resistance in injected and machined lithium disilicate ceramics. Methods: lithium disilicate disks, IPS e. were used Max CAD (Ivoclar Vivadent, Liechtenstein, Swiss), 10mm in diameter and 1mm in thickness embedded in PVC tubes. Was distributed in 4 working groups, 2 in injected lithium ceramics and 2 in machined, Palfique Bond and Tetric N-bond Universal adhesives were applied according to the group distribution, then photopolymerized for 10 seconds with led light bulb, Tygon® tubes were placed for filling with fluid resin; once the Tygon® tubes were removed. The samples were taken to a universal testing machine where the micro-spraying test was performed. Results: the most significant binding resistance values were found in lithium disisilicate ceramics adhered with the Palfique Bond and Tetric Bond adhesive having a significant difference (p= 0,001), the bond strength values of the Palfique Bond and Tetric Bond adhesive in injected ceramic did not differ significantly. Conclusion: machined lithium disilicate ceramics have better values of binding resistance to micro-spraying.

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The cellulose from agroindustrial waste can be treated and converted into nanocrystals or nanofibers. It could be used to produce biodegradable and edible films, contributing to the circular economy and being environmentally friendly. This research aimed to develop an edible film elaborated with activated cellulose nanocrystals, native potato starch, and glycerin. The activated cellulose nanocrystals were obtained by basic/acid digestion and esterification with citric acid from corn husks. The starch was extracted from the native potato cultivated at 3500 m of altitude. Four film formulations were elaborated with potato starch (2.6 to 4.4%), cellulose nanocrystals (0.0 to 0.12%), and glycerin (3.0 to 4.2%), by thermoforming at 60 °C. It was observed that the cellulose nanocrystals reported an average size of 676.0 nm. The films mainly present hydroxyl, carbonyl, and carboxyl groups that stabilize the polymeric matrix. It was observed that the addition of cellulose nanocrystals in the films significantly increased (p-value < 0.05) water activity (0.409 to 0.447), whiteness index (96.92 to 97.27), and organic carbon content. In opposition to gelatinization temperature (156.7 to 150.1 °C), transparency (6.69 to 6.17), resistance to traction (22.29 to 14.33 N/mm), and solubility in acidic, basic, ethanol, and water media decreased. However, no significant differences were observed in the thermal decomposition of the films evaluated through TGA analysis. The addition of cellulose nanocrystals in the films gives it good mechanical and thermal resistance qualities, with low solubility, making it a potential food-coating material.

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The aim was to evaluate the effect of residual feed intake (RFI) on the histological, physical and mechanical characteristics of the sheep skin confined in full sun or shade. Dorper sheep (n = 64), male, with an initial bodyweight of 17.8 ± 2.43 kg was confined for 40 days to determine the RFI. After classification, 30 animals with positive RFI and 30 animals with negative RFI were selected, which were distributed in 2 confinement environments. This was a factorial arrangement of 2 (groups of animals-positive RFI and negative RFI) × 2 (environments-full sun and shade), with 15 animals for each combination of factors. The sheep remained in confinement for 60 days. After slaughter, skins were divided in half, and fragments were collected from the right portion for histological sections. The left part of each skin was subjected to tanning. Interaction effect RFI × environment was found in the evaluation of leather fragments in the horizontal direction on elongation at break, leather thickness and tear strength (p < 0.05). An isolated effect of the environment was found on elongation at break of leather fragments in the evaluation on the vertical direction (p = 0.01) and on the number of secondary follicles during the histological evaluation of the dorsal and lateral regions of the skin (p < 0.05). An effect of the interaction RFI × environment was observed for the thermostatic layer of the hip region (p = 0.03). Sheep with positive RFI and kept in confinement in full sun have a leather with greater elongation at break and tear strength, important aspects in determining the quality of the product by the leather industry.

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Introduction: The knee has shown a significant increase in the frequency of injury due to sports practice. This increase and the improvement of surgical techniques of ligament reconstruction have led to a greater indication of this treatment to achieve a function close to normal. Objective: To conduct a preliminary analysis of the ligament behavior. Methods: The study consisted of the validation of an anatomical model of the pig, in which five models were subjected to mechanical tests. The data on the loads of the in situ model and the strains of the posterior cruciate ligament were collected. Results: The analysis of the tensile load showed, at first, a nonlinear increase in stresses. Subsequently, the pig's knee showed a relatively linear intermediate response until failure around 1,200 N. Strain × time showed a response of the posterior cruciate ligament, which also has a relatively linear response. Conclusion: We observed a linear behavior in the range of 1,000 to 5,000 microstrains in the strain of the posterior cruciate ligament. We suggest further studies to understand knee ligaments regarding their behavior in their function. Level of Evidence IV, Biomechanical Study.

Introdução: O joelho tem demonstrado um aumento significativo de frequência de lesão devido à prática esportiva. Esse aumento e a melhoria das técnicas cirúrgicas de reconstrução ligamentar têm levado a maior indicação desse tratamento com o objetivo de se atingir uma função próxima do normal. Objetivo: Realizar uma análise preliminar do comportamento ligamentar. Métodos: O estudo consistiu na validação de um modelo anatômico do porco, em que cinco modelos foram submetidos a ensaios mecânicos. Foram coletados os dados das cargas do modelo in situ e das deformações do ligamento cruzado posterior. Resultados: Na análise da carga trativa, foi observado que em um primeiro momento existe um aumento não linear das tensões. Em sequência, há uma resposta intermediária relativamente linear do joelho suíno até a falha em torno de 1.200 N. A deformação versus tempo mostrou uma resposta do ligamento cruzado posterior, que também possui uma resposta relativamente linear. Conclusão: Observou-se um comportamento linear na faixa de 1.000 até 5.000 microstrains na deformação do ligamento cruzado posterior. Sugerem-se novos estudos para a compreensão dos ligamentos do joelho quanto ao comportamento deles na sua função. Nível de Evidência IV, Estudo Mecânico.

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AIM: To assess dentin-post bond strength and mode of failure through tensile strength testing of two endodontic post systems: CAD/CAM custom-milled fiber posts vs Splendor SAP. MATERIALS AND METHODS: Thirty extracted single-rooted mandibular premolars were sectioned 2 mm coronal to the cementoenamel junction. Root length was standardized at 15 mm, and the root canals were instrumented with #20 K-files followed by 30/0.03 and 30/0.05 ProDesign Logic rotary files, under irrigation with 2.5% NaOCl, and then submitted to final irrigation with 17% EDTA. Canals were filled with gutta-percha and AH PLUS sealer. After 24 hours, the teeth were prepared for post placement to a depth of 10 mm and randomly allocated into two experimental groups (n = 15): CAD/CAM (CC) and Splendor SAP (SS). All posts were cemented with RelyX U200 dual-cure self-adhesive resin cement. The roots were embedded in acrylic resin, and the specimens were stored for 7 days in moist heat (37°C). Tensile strength testing until failure was then performed in a universal testing machine using a crosshead speed of 0.5 mm/minute. The final failure load was tabulated for statistical analysis, and the G test was used to compare the failure modes observed under light microscopy (5× magnification). RESULTS: There was no significant difference between groups regarding tensile bond strength to root dentin (p = 0.325). Conversely, failure mode differed significantly between groups (p = 0.037). CONCLUSION: The tensile bond strength observed for the CAD/CAM and Splendor SAP post systems was similar. Adhesive failure was predominant in both groups; however, the CAD/CAM custom-milled fiber posts failed predominantly at the dentin-resin cement interface, whereas Splendor SAP posts failed mostly at the post-resin cement interface. CLINICAL SIGNIFICANCE: A strong post-dentin bond is a key to the success of dental restorations and prosthetic rehabilitation. In teeth with severe coronal decay and wide canals, both of the tested systems would be able to achieve good cervical fit.

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Purpose: Bulk-fill composite resins were developed to reduce time and facilitate the restorative procedure. However, considering their recent introduction on the market and the new formulations, their performance still requires evaluation. This study aimed to evaluate Knoop microhardness (KHN), diametral tensile strength (DTS) and degree of conversion (DC) of three Bulk-Fill composite resins and a conventional one. Materials and Methods: Sixty samples (n = 15; 8 mm ø x 4 mm height) were confectioned using a mold. Filtek Bulk-Fill (FBF), Tetric N-Ceram Bulk-Fill (TNC) and SonicFill 2 (SF2) were placed in 4 mm increments, and Filtek Z350 (FZ350) was placed in 2 mm increments. The KHN of top and bottom surfaces were tested using Knoop Hardness tester at 10 gf/10s. The DTS was tested under compressive load at 1.0 mm/min. The DC was measured by Fourier Transform Infrared (FTIR) spectroscopy. Differences in DTS and DC were analyzed by ANOVA and Tukey post hoc test. For KHN, Kruskal-Wallis and Wilcoxon tests were performed at α = 0.05. Results: Top surfaces of all composite resins had higher KHN than bottom surfaces. At top and bottom surfaces, FZ350 showed higher KHN than TNC and SF2. The highest DTS was obtained by FBF, followed by FZ350 and SF2. The highest DC was obtained by SF2, the lowest one was obtained by FBF. Conclusion: From Bulk-Fill composite resins, FBF presented the best KHN and DTS results. The SF2 showed the best DC. Further studies are required to ensure whether these differences can negatively influence the behavior of in vivo restorations.

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OBJETIVO Determinar la resistencia máxima a la tracción (RMT) de la continuación prepatelar del cuádriceps (CPC).MATERIALES Y MÉTODOS Se realizó un estudio en cadáveres humanos. Fueron incluidos diez especímenes, en los cuales se utilizaron los tercios proximal y medial de la cortical anterior de la patela para evaluar las propiedades mecánicas de la CPC. En cada espécimen, se estudió un área de sección transversal de 0,2 cm2 (A1) y 1 cm2 (A2). Se aplicó una carga gradual para determinar la RMT.RESULTADOS La mediana de la RMT en el A1 fue de 232,56 N (rango: 141,23 N a 295,33 N) y en el A2 fue de 335,30 N (rango: 216,45 N a 371,40 N). El incremento en la TMR fue significativo entre las 2 áreas (p = 0,006).CONCLUSIÓN El ignificado clínico de este estudio es que la CPC es un tejido fuerte que puede servir de anclaje seguro para reconstrucciones alrededor de la patela. Un área relativamente pequeña tolera al menos 140 N y, a medida que crece el área, también aumenta la RMT.

OBJETIVE To determine the ultimate tensile strength (UTS) of the prepatellar quadriceps continuation (PQC). MATERIALS AND METHODS A human cadaveric study was performed. Ten fresh-frozen specimens were used. The proximal and medial thirds of the anterior cortex of the patella were used to assess the mechanical properties of the PQC. In each specimen, transverse section areas measuring 0.2 cm2 (A1) and 1 cm2 (A2) were studied. A gradual load was applied to determine the UTS. RESULTS The median UTS of A1 was of 232.56 N (range: 141.23 N to 295.33 N), and that of A2 was of 335.30 N (range: 216.45 N to 371.40 N). The increment in UTS was significant between the 2 areas (p » 0.006). CONCLUSION The clinical significance of the present study lies in the fact that it shows that the PQC is a strong tissue that can be a safe anchor for reconstruction around the patella. A relatively small area supports at least 140 N, and, as the area grows, the UTS increases as well.

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PURPOSE: This in vitro study evaluated the microshear bond strength (µSBS) of a universal adhesive after silver diammine fluoride (SDF) application at different concentrations on carious dentinal lesions in primary teeth. METHODS: Flat dentin carious-induced surfaces from 40 primary molars were randomly assigned to four experimental groups: without SDF treatment (control), 12% SDF, 30% SDF, or 38% SDF application. After 14 days of storage in artificial saliva at 37 °C, a universal adhesive system (Scotchbond Universal, 3 M ESPE) was applied in the etch-and-rinse mode and resin composite cylinders were built (0.72 mm2). After 24 h of water storage, the µSBS test was performed and the failure mode was determined. Data were analysed using one-way ANOVA and Tukey's post hoc tests (α = 0.05). RESULTS: The application of 38% SDF resulted in higher µSBS mean than control and use of 12% SDF (p = 0.006). No significant differences were observed among control, 12% SDF, and 30% SDF. All specimens tested showed adhesive/mixed failure. CONCLUSION: The use of SDF does not jeopardise the bonding of a universal adhesive applied in the etch-and-rinse mode to carious dentinal lesions in primary teeth, irrespective of the product concentration.

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