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To evaluate i) the inhibitory and bactericidal activity of cashew nut shell liquid (CNSL) and its isolated compounds (anacardic acid and cardol) against oral bacteria; ii) the biofilm formation inhibition, resin-dentin bond strength and physicochemical properties of a dental adhesive incorporated with these substances. The antibacterial effect of CNSL, anacardic acid, and cardol were assessed by determining the minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations. Effect in inhibiting biofilm formation of the adhesive incorporated with the substances (15 μg/ml) against a mixed-species biofilm of Streptococcus mutans and Candida Albicans and was determined by direct contact test. Additional Analysis included microtensile bond strength (μTBS) test, elastic modulus (EM), flexural strength (FS), degree of conversion (DC), water sorption (WS) and solubility (SL). The data were submitted to statistical analysis by one-way ANOVA and Tukey’s test (p

Este trabalho apresenta a resenha do livro "Mídia e Educação: novos olhares para a aprendizagem sem fronteiras", organizado pelos pesquisadores Raul Inácio Busarelo, Patrícia Bienging e Vânia Ribas Ulbricht. Esta obra se apresenta em nove capítulos, que tem a objetivo expor e discutir nove pesquisas educacionais que utilizaram as mídias como recurso metodológico

To evaluate the effects of pretreatment with different crosslinking agents on glass-fiber-post adhesive luting.Single-rooted human teeth (n = 20) were randomly assigned to four groups: proanthocyanidins (PA) from grape-seed extract, cardol and cardanol (separated from cashew nut-shell liquid) and negative control (hydroethanolic solution). The solutions were applied on 37% phosphoric acid-etched dentin for 60 s. Glass-fiber posts were cemented using a three-step etch-and-rinse adhesive (Scotchbond Multi-Purpose, 3M Oral Care) and composite cement (RelyX ARC, 3M Oral Care). Slices for the push-out bond strength test were cut and tested after 24-h or 6-month storage in distilled water. The dentin underlying the adhesive layer was analyzed by micro-Raman spectroscopy to evaluate vibrational formation of collagen crosslinks. Three additional slices per group were also made and the adhesive in-situ degree of conversion (DC) was analyzed by micro-Raman spectroscopy. The results were analyzed using two-way ANOVA and Tukey's test (p0.05).No statistically significant changes in bond strength were found over time for any of the groups, except with cardol, which increased bond strength (8.4 ± 3.9 MPa at 24 h to 15.0 ± 2.9 MPa after 6 months, p0.001) after aging. The formation of peaks at 1117 cm-1 and 1235 cm-1 showed the presence of collagen crosslinks for all three biomodification agents. The DC outcomes showed no statistically significant differences between groups (p = 0.514).Biomodification agents did not impair adhesive polymerization. Cardol demonstrated a positive influence on intraradicular dentin bonding for glass-fiber post luting.

The aim of the study was to assess the degree of conversion (DC), microhardness, polymerization shrinkage stress (PSS) and volumetric contraction of two bulk-fill composites (SonicFill, Kerr Corporation, Orange, CA, USA - (SF) and Filtek BulkFill, 3M ESPE, St Paul, MN, USA - (FB)) and one conventional nanofiller resin composite (Z350XT – 3M ESPE, St Paul, MN, USA) inserted incrementally (Z350I) or in bulk (Z350B). Micro-Raman spectroscopy, Knoop microhardness, PSS test and micro-computed tomography technique (μCT) were used to evaluate the resin composites. Data were analyzed with one-way ANOVA followed by Tukey’s post hoc test (α = 0.05). DC was not affected by the type of the composite, excepted when conventional resin composite was inserted in a single increment (p = 0.002). FB and Z350I showed higher microhardness values than Z350B (p = 0,003), while SF showed no statistically significant difference to the other resin composites. No statistical differences were found among the composites regarding to PSS (p = 0.104) and volumetric shrinkage (p = 0.258). Therefore, it can be concluded that bulk-fill and conventional resin composites tested present similar properties. Thus, shorter time required for the use associated with simplified operative technique are considered clinical advantages of bulk-fill composites.

The aim was to evaluate the antibacterial and antibiofilm activity of natural (n-CNSL) and technical (t-CNSL) cashew nut shell liquid against streptococci and enterococci related to dental caries and chronic apical periodontitis, respectively.Minimum inhibitory concentrations (MIC) and minimal bactericidal concentration (MBC) were determined to assess the antimicrobial effect of both CNSLs (n-CSNL and t-CNSL) against S. oralis ATCC 10557, S. sobrinus ATCC 6715, S. parasanguinis ATCC 903, S. mutans UA 159 and E. faecalis ATCC 19433. The antibiofilm activity was evaluated by total biomass quantification, colony forming unit (CFU) counting and scanning electron microscopy (SEM). Furthermore, cytotoxic effect of the substances was evaluated on L929 and HaCat cell lines by MTS assay.The n-CNSL and t-CNSL showed inhibitory and bactericidal effect against all strains tested in this study, with MIC and MBC values ranging from 1.5 to 25 μg/mL. Overall, both CNSLs showed significant reduction in biomass quantification and enumeration of biofilm-entrapped cells for the strains analyzed, in biofilm formation and preformed biofilms (p 0.05). In biofilm inhibition assay, the t-CNSL and n-CNSL showed reduction in biomass and CFU number for all bacteria, except in cell viability of S. parasanguinis treated with t-CNSL (p 0.05). Indeed, SEM images showed a reduction in the amount of biomass, bacterial cells and changes in cellular morphology of S. mutans.In conclusion, both substances showed effective antibacterial and antibiofilm activity against the strains used in the study, except in viability of S. parasanguinis cells treated with t-CNSL.

Objectives The EDTMP (ethylenediamine-tetra-methylene phosphonate) is a molecule similar to EDTA (ethylenediamine-tetra-acetic acid), but with phosphonates, thereby presenting efficient chelating action and binding adequately to proteins, such as collagen. The objective of this study was to evaluate EDTMP as new etching solution to aid ion-releasing adhesive containing beta-tri-calcium phosphate (β-TCP) fillers used for intrarradicular dentin bonding. Materials and methods Thirty extracted single-rooted human teeth were prepared, and glass-fiber posts were adhesively luted with Scotchbond Multipurpose (SBMP, 3 M) adhesive after etching with 37% phosphoric acid for 15s, 15% EDTA or 15% EDTMP for 120s, and SBMP adhesive incorporated or not with β-TCP. RelyX ARC (3 M) was used as resin cement. The restored roots were cut horizontally in 1 mm-thick slabs and submitted to push-out bond strength test after 24h and 6 months of water storage. Interfacial silver nanoleakage was investigated in scanning electron microscopy. Micro-Raman spectroscopy was employed to track mineralization at the hybrid layer. Data were submitted to two-way ANOVA and Tukey’s test (p Results EDTMP without β-TCP achieved the overall highest bond strength in both storage times. The addition of β-TCP impaired the improvements of EDTMP. The presence of carbonated apatite (peak at 1090 cm-1) was found in EDTMP without β-TCP, thereby suggesting remineralization. Little silver impregnation was observed in general across groups. Conclusion: EDTMP could be an optimal alternative as root dentin etchant for luting glass-fiber posts with improvements in dentin bond stability.

Objectives Several polyphenols from renewable sources were surveyed for dentin biomodification. However, phenols from cashew nut shell liquid (CNSL, Anacardium occidentale) and from Aroeira ( Myracrodruon urundeuva ) extract have never been evaluated. The present investigation aimed to compare the dentin collagen crosslinking (biomodification) effectiveness of polyphenols from Aroeira stem bark extract, proanthocyanidins (PACs) from grape-seed extract ( Vitis vinifera ), cardol and cardanol from CNSL after clinically relevant treatment for one minute. Methods Three-point bending test was used to obtain the elastic modulus of fully demineralized dentin beams before and after biomodification, whilst color change and mass variation were evaluated after four weeks water biodegradation. Color aspect was assessed by optical images after biodegradation whereas collagen cross-linking was investigated by micro-Raman spectroscopy. Statistical analysis was performed with repeated-measures two way ANOVA and Tukey’s test (p Results The increase in elastic modulus after biomodification was in the order cardol > cardanol > aroeira = PACs with cardol solution achieving mean 338.2% increase. The mass increase after biomodification followed the same order aforementioned. Nevertheless, after four weeks aging, more hydrophobic agent (cardanol) induced the highest resistance against water biodegradation. Aroeira and cardol attained intermediate outcomes whereas PACs provided the lower resistance. Tannin-based agents (Aroeira and PACs) stained the specimens in dark brown color. No color alteration was observed with cardol and cardanol treatments. All four agents achieved crosslinking in micro-Raman after one minute application. Significance In conclusion, major components of CNSL yield overall best dentin biomodification outcomes when applied for one minute without staining the dentin collagen.

O objetivo foi avaliar os efeitos de agentes biomodificadores dentinários como pré-tratamento na cimentação de pinos de fibra de vidro. As soluções foram preparadas e os grupos foram divididos de acordo com os agentes biomodificadores: proantocianidina da semente da uva (PAC), cardol e cardanol (extraídos do líquido da castanha de caju) e controle negativo (sem tratamento). As soluções foram aplicadas antes do sistema adesivo em 20 raízes de dentes unirradiculares (n5) extraídos e então os pinos de fibra de vidro foram cimentados com cimento resinoso RelyX ARC (3M). As fatias para o teste de push-out foram cortadas e testadas após 24h ou 6 meses de armazenamento em água destilada. A dentina subjacente foi analisada pela espectroscopia micro-Raman para avaliar a formação de ligações cruzadas de colágeno. Três fatias também foram separadas e analisado o grau de conversão (GC) “in situ” do adesivo pela redução do pico 1639 cm-1 por espectroscopia micro-Raman. Os resultados foram analisados com ANOVA e teste de Tukey (p0,05) entre os grupos. Foi verificada a formação dos picos 1117cm-1 e 1235 cm-1 referentes as ligações cruzadas em todos os grupos experimentais em 6 meses. O GC mostrou não mostrou diferença estatística entre os grupos. Portanto, os agentes biomodificadores mostram-se promissores para serem utilizados intra-canal na cimentação de pinos de fibra de vidro.Palavras-chave: Dental Cements. Cross-Linking Reagents. Anacardium Occidentale.

O estudo avaliou sistemas adesivos experimentais contendo EGCG com nanopartículas de hidroxiapatita (Hap) em relação às propriedades físicas e de união à dentina. Para os ensaios foram utilizados sistemas adesivos experimentais (convencional e autocondicionante (AC) sem adição de EGCG ou Hap (controle) e adicionados de EGCG/Hap nas concentrações de 1% e 5%. As propriedades de resistência à flexão (RF) e módulo de elasticidade (ME) dos sistemas adesivos foram avaliadas através de ensaios de flexão, onde os melhores resultados foram encontrados para o grupo AC contendo EGCG/Hap 5% (127,8(RF) e 933,3(ME)), porém os outros grupos não apresentaram diferenças estatísticas entre si. A adesão à dentina foi avaliada por teste de microtração após 24h ou 06 meses de armazenamento. No grupo convencional com EGCG/Hap 1% mostrou maior estabilidade e nos autocondicionantes os melhores resultados foram no EGCG/Hap 5%, sendo estatisticamente semelhante ao controle. A estatística foi realizada com Análise de Variância (ANOVA) dois fatores e teste de Tukey (p

O objetivo foi avaliar os efeitos de uma restauração adesiva utilizando o EDTF (etilenodiamino tetrametileno-fosfonato) como solução condicionadora e o adesivo contendo beta-tri-cálcio fosfato (þ-TCP) na resistência de união e estabilidade de adesão de pinos de fibra de vidro em dentina radicular. Para tanto 30 dentes humanos unirradiculares extraídos foram selecionados. A restauração intracanal foi realizada com pino de fibra de vidro (Angelus) e a cimentação com o cimento resinoso dual RelyX ARC (3M). As raízes restauradas foram cortadas em fatias de 1mm de espessura e submetidas ao teste de resistência de união ao push-out após 24 horas e 6 meses de armazenamento em água destilada. Os grupos foram divididos de acordo com a solução condicionadora e o sistema adesivo com e sem acréscimo de þ-TCP. O sistema adesivo foi o Scotchbond Multi Purpose (3M). As soluções condicionadoras utilizadas foram o ácido fosfórico a 37%, EDTA 15% (ácido etilenodiamino tetra-acético) e EDTF 15%. Os dados foram submetidos à ANOVA dois fatores e teste de Tukey (p