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OBJECTIVE: The aim of this study was to evaluate whether fluconazole (FLZ) could affect the bioactivity and cellular structure of Candida albicans or Candida glabrata biofilms grown in the presence of FLZ. MATERIALS AND METHODS: Tokens were fabricated using poly(methylmethacrylate) resin (PMMA) in a hot water bath. Salivary pellicles were formed on the PMMA surface, and biofilms of a reference strain and two clinical isolates of C. albicans (ATCC 90028, P01 and P34) and C. glabrata (ATCC 2001, P11 and P31) were developed for a period of 48 h. Control and experimental groups were formed. FLZ at the bioavailable concentration in saliva (2.56 µg/mL) was added to the medium of the experimental group. The culture mediums of the control and experimental groups were changed after 24h. The bioactivities of the biofilms were evaluated using an XTT reduction colorimetric assay. The cellular structure was analysed by confocal scanning laser microscopy and by transmission electron microscopy. The data were analysed by the independent sample Student's t-test, with the significance level set at 5%. RESULTS: The presence of FLZ decreased the bioactivity of all C. albicans biofilms (p<0.001), however, it did not change the cellular structure of C. albicans P34. Regarding the C. glabrata biofilm bioactivity and structure, no statistically significant differences were found between the control and experimental groups. CONCLUSION: FLZ, at the bioavailable concentration present in saliva, interferes with the development of C. albicans biofilms, but does not interfere with the development of C. glabrata biofilms.

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Food allergy is an immunologically mediated adverse reaction to food protein. Cow's milk protein allergy (CMPA) is the most frequent type and is the one that is most difficult to diagnose. This study had the objective of analyzing the accuracy of hypersensitivity and specific IgE skin tests among children with CMPA and predominantly gastrointestinal clinical manifestations. The participants in this study were 192 children aged one and five (median of 2 yr). Among these, 122 underwent open oral challenge to the suspected food. After evaluating the sensitivity, specificity and positive and negative predictive values (respectively, PPV and NPV) of skin and specific IgE tests in relation to the gold standard (open oral challenge); all the children underwent the skin prick test (SPT), specific IgE test and atopy patch test (APT) for cow's milk, eggs, wheat and peanuts and the open oral challenge for the food to which the child was sensitive or had suspected sensitivity. Presence of food allergy was confirmed for 50 children (40.9%). Among these cases, 44/50 (88%) were of allergy to cow's milk protein. Children who presented a positive response to an oral challenge to cow's milk protein were considered to be cases, while the controls were children with negative response. Twenty-two of the 44 cases (50.0%) presented symptoms within the first 4 h after the challenge. The SPT presented 31.8% sensitivity, 90.3% specificity, 66.7% PPV and 68.4% NPV. The APT presented 25.0% sensitivity, 81.9% specificity, 45.8% PPV and 64.1% NPV. The specific IgE test presented, respectively, 20.5%, 88.9%, 52.9% and 64.6%. Despite the operational difficulty and the possible exposure risk, oral challenge is the best method for diagnosing CMPA, because of the low sensitivity and PPV of skin and specific IgE tests.

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Successful restoration depends on the mechanical resistance of dental restorative materials. The occlusal forces from masticatory contacts can affect the durability of restorations and cause fractures. Over time, monomers convert to polymers, leading to degradation of the organic matrix, which can interfere with mechanical resistance. This study sought to assess the effect of artificially accelerated aging on the microhardness of five composite resins: Filtek Z250, Charisma, Durafill VS, Filtek Supreme for body, and Filtek Supreme translucent. Ten test specimens were made of each material, using a 6.0 x 2.0 mm teflon matrix. After 24 hours, five test specimens of each material were submitted to the Vickers microhardness test (control group) for 10 seconds at a load of 300 kgf. The other five test specimens remained in the artificially accelerated aging machine for 196 hours and were submitted to the Vickers microhardness test. Filtek Z250 had the highest values and Durafill the lowest, both at 24 hours and after artificially accelerated aging. Artificially accelerated aging increased the microhardness of the composite resins.

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El termocondicionador es un aparato de construcción simple y costo reducido, que tiene por objetivo el de facilitar al Cirujano Dentista la manipulación de resina acrílica para realizar trabajos clínicos en los que su uso es necesario. Con este artículo se pretende mostrar la técnica de confección de un termocondicionador así como sus aplicaciones clínicas

The termoconditioning is a piece of equipment of simple construction and reduced cost, which provides comfort to the dentist when he performs clinical functions when the use of acrylic resin is necessary. The objective of this article is to demonstrate the making technique of one termoconditioning and its clinical applications

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OBJECTIVE: The aim of this study was to investigate the shear strength between distinct associations of different commercial composite resins and their fracture modes. METHODS: Nine composite-composite associations (n=90) were prepared for shear strength evaluation and separated into the following groups: Z/Z (Filtek Z250 UD+Filtek Z250 A2); Z/D (Filtek Z250 UD+Durafill VS A2); Z/S (Filtek Z250 UD+Filtek Supreme YT); C/C (Charisma OA2+Charisma A2); C/D (Charisma OA2+Durafill VS A2); C/S (Charisma OA2+Filtek Supreme YT); H/H (Herculite XRV B2D+Herculite XRV B2E); H/D (Herculite XRV B2D+Durafill VS A2); H/S (Herculite XRV B2D+Filtek Supreme YT). Shear tests were carried out using universal mechanical test equipment with a load of 200kgf and speed of 0.5mm/min. Ultimate shear strength data (MPa) from all tested groups were submitted to analysis of variance (one-way ANOVA) and the Tukey test. The fractured surfaces of the test samples were visually evaluated by binocular stereomicroscope at 20 times magnification. Fractures were classified as either adhesive or cohesive or mixed. RESULTS: The highest ultimate shear strength observed for composite-composite associations was found for the groups: Z/Z, C/S, H/H, H/S, Z/S and C/C. Those associations containing the Durafill resin were weaker than the others. CONCLUSION: Microparticle RBC associations presented lower shear strength than hybrid and/or nanoparticle RBC associations, once the only significant difference was found when the Durafill resin was involved.

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The purpose of this study was to evaluate the adherence of Streptococcus mutans to the surface of direct-use composites submitted to different polishing techniques. Cylindrical specimes were made of resins: Filtek Z250®; Filtek A110®; Filtek P60® and Filtek Supreme®. The samples were grouped in accordance with the surface treatment: poliester matrix (without polishing); brush technique (without polishing); Sof-Lex® disks; fine grain and extra-fine grain diamond points; carbide burs with 12 and 30 blades; diamond points associated with silicone points (Enhance® system); and multibladed burs associated with silicon points. In a sterile laminar flux apparatus the samles were disinfected and placed in Petri dishes where BHI sucrose broth was added and S. mutans ATCC 25175 was inoculated in a such a manner that the study surface was turned upwards (incubation at 35+ - 2°C). After 24 and 72 hours, three previously calibrated examiners used a stereomicroscope to classify the samples with regard to the presence and thickness of the pellicle and quantity of colonies. The data were statistically analyzed nonparametric tests of Mann Whitney and Student-New-man-Keuls (p<0,05). The microhybrid resin exhibited the same indexes of adherence when compared to both the microparticle and the nanoparticle, and lower adherence than packable composite.Among the polishing systems, the most effective were the multibladed burs and diamond points used before the silicon points. For the obtainment of a smooth surface by means of polishing, it is necessary to inhibit the impregnation of bacteria on the composite resin restorations.

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Para realização deste estudo vinte condutos artificiais foram construídos em blocos formados por esmaltee dentina, a partir de dentes bovinos. Dez pinos de fibra de vidro e dez de fibra de carbono foram cimentadosnos condutos com cimento resinoso C&B. Empregou-se matriz de policarbonato para confecção do coreem resina composta, perfazendo quatro grupos: Grupo (1) pino de fibra de vidro e core com resina compostaCharisma; Grupo (2) pino de fibra de carbono e core com resina composta Charisma; Grupo (3) pino defibra de vidro e core com resina composta reforçada Enforce-core; Grupo (4) pino de fibra de carbono ecore com resina composta reforçada Enforce-core. Os ensaios mecânicos de compressão foram realizadosna máquina universal de ensaios EMIC DL 2000, com célula de carga 2000kgf e velocidade 1mm/mim.Verificou-se diferença estatística (p<0,05) (ANOVA) somente do fator resina no que tange as medidas daresistência à fratura do core, além disso, não há uma influencia significativa do tipo de fibra e nem mesmoda interação entre os fatores (resina x fibra). A conclusão para um fator é a mesma independentemente donível do outro fator. Os resultados para os dentes com resina composta reforçada diferem significativamentedos dentes que utilizaram resina composta não reforçada, onde, os dentes com resina composta reforçadaapresentaram medidas de resistência significativamente superiores aos dentes que utilizaram resina compostanão reforçada, independentemente do tipo de fibra (Teste de DUNCAN). Portanto, a fibra não influencia noresultado de resistência.

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O objetivo deste estudo foi avaliar o pH de agentes clareadores a base de carbamida a 10 por cento e 16 por cento disponíveis comercialmente Whiteness Standard (FGM), Review (SSWhiate) e Whteness Perfect (FGM) e manipulados em farmácia de manipulação. A análise do pH foi conduzida utilizando um pHmetro Micronal B474, calibrado em 4,00 e 7,00 com solução tampão ácido cítrico/hidrogênio fosfato de sódio, empregando-se solução KCl 3 mol L. Três gramas de cada amostra foram depositadas em tubo de ensaio recobrindo todo bulbo do eletrodo. O processo foi repetido 8 vezes para cada agente clareador. O eletrodo era lavado entre cada amostra usando água corrente e ácido acético a 4 por cento para remoção completa do agente clareador. O eltrodo foi lavado com água destilada, seco com papel absorvente e a calibração conferida. Aguardava-se 3 minutos para cada leitura, em temperatura ambiente de 24±1ºC. O pH dos produtos clareadores variou de 4,060 (agente manipulado 10 por cento) a 6,212 (Whiteness Standard 10 por cento)...

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