A new preheating thermoviscous composite for restoration of non-carious cervical lesions: a 6-month randomized clinical trial / Um novo compósito termoviscoso de pré-aquecimento para restauração de lesões cervicais não cariosas: ensaio clínico randomizado de 6 meses

Objetivo: Este ensaio clínico randomizado, duplo-cego e boca dividida avaliou o desempenho clínico de um novo compósito termoviscoso com pré-aquecimento (PHT) em comparação com uma resina composta sem aquecimento (NHT) em restaurações de lesões cervicais não cariosas (LCNCs) durante um período de 6 meses. Material e Métodos: 120 restaurações foram realizadas em LCNCs com dois materiais restauradores (n = 60). Após a profilaxia, os dentes foram isolados com isolamento de fio retrator/rolos de algodão e um adesivo universal foi aplicado na estratégia de condicionamento seletivo do esmalte. Para o grupo PHT o aquecimento foi realizado a 68°C usando um aquecidor de bancada por 3 min. Por outro lado, para o grupo NHT, nenhum aquecimento foi aplicado. Ambos os materiais restauradores foram colocados no dispensador de cápsulas e inseridos nas LCNCs. Após 6 meses, o desempenho clínico das restaurações foi avaliado de acordo com os critérios FDI. A análise estatística foi realizada com teste Qui-quadrado para todos parâmetros da FDI (α = 0,05). Resultados: Apenas três restaurações no grupo NHT foram perdidas/fraturadas após seis meses de acompanhamento. As taxas de retenção (intervalo confiança 95%) por seis meses foram de 97,5% (88,6% - 99,0%) para o grupo NHT e 100% (93,9% - 100%) para o grupo PHT (p > 0,05). Vinte e duas restaurações (8 para NHT e 14 para PHT) apresentaram pequenos defeitos de adaptação marginal aos seis meses de acompanhamento (p > 0,05). Vinte e seis restaurações apresentaram alguma retenção de biofilme aos seis meses de acompanhamento (11 para NHT e 15 para PHT; p > 0,05). Em relação a todos os outros parâmetros de FDI avaliados, todas as restaurações foram consideradas clinicamente aceitáveis. Conclusão: O desempenho clínico do novo compósito termoviscoso de pré-aquecimento mostrou-se promissor após 6 meses de avaliação clínica quando aplicado em LCNCs.(AU)

Objective: This double-blind, split-mouth randomized clinical trial evaluate the clinical performance of a new preheating (PHT) thermoviscous composite compared to a non-heating (NHT) composite resin in restorations of non-carious cervical lesions (NCCLs) over a period of 6-month. Material and Methods: 120 restorations were performed on NCCLs with two restorative materials (n = 60). After prophylaxis, the teeth were isolated with retraction cord isolation/cotton rolls and one universal adhesive was applied in the selective enamel etching strategy. For the PHT group heating was carried out at 68°C using a heater bench for 3 min. On the other side, for the NHT group, no heating was applied. Both restorative materials were placed in the caps dispenser and inserted in the NCCLs. The restorations were evaluated after 6-month of clinical performance according to the FDI criteria. Statistical analysis was performed with Chi-square test for all FDI parameters (α = 0.05). Results: Three restorations only in the NHT group were lost/fractured after six months follow-up. The retention rates (confidential interval 95%) for six months were 97.5% (88.6% - 99.0%) for the NHT group and 100% (93.9% - 100%) for the PHT group (p > 0.05). Twenty-two restorations (8 for NHT and 14 for PHT) presented small marginal adaptation defects at the six-months follow-up (p > 0.05). Twenty-six restorations were found to have biofilm retention in the six-month recall (11 for NHT and 15 for PHT; p > 0.05). Regarding all others FDI parameters evaluated, all restorations were considered clinically acceptable. Conclusion: The clinical performance of the new preheating thermoviscous was found to be promise after 6-month of clinical evaluation when applied in NCCLs (AU)

Evaluation of Residual Monomer Release After Polymerization of Colored Compomer Materials

ABSTRACT Objective: To evaluate the amount of residual monomers released after polymerization by the compomers in different colors and viscosities over time. Material and Methods: The compomer samples of different colors and viscosities (flowable compomers; blue-pink and packable compomers; A2-blue-pink-gold) were prepared in molds with an inner diameter of 5 mm and a height of 2 mm. In polymerization of samples, a LED unit was used. The amount of monomers released from the samples kept in 75% ethanol/water solution was measured by a high-performance liquid chromatography (HPLC) instrument in the 10th minute, in the 1st hour, and in the 1st, 7th, and 14th days. For statistical analyses, the paired sample t-test, independent sample t-test, and one-way ANOVA with Tukey's post hoc test were used. Results: The amount of residual monomers released from all materials increased over time. At the end of the 14th day, the most released monomer from all compomer samples was BisGMA. The total amounts of released monomers from the packable compomers were Gold>A2>blue>pink. The amount of residual monomers released from flowable compomers was higher in blue than in pink. Conclusion: The color and the viscosity are the factors affecting the residual monomer release in compomers.

Spectrophotometric Analysis of Streptococcus mutans Growth and Biofilm Formation in Saliva and Histatin-5 Relate to pH and Viscosity

ABSTRACT Objective: To analyze the ability of saliva in controlling the growth and the biofilm formation of Streptococcus mutans (S. mutans) as well as the effect of histatin-5 anti-biofilm relate to pH and saliva viscosity. Material and Methods: The S. mutans biofilm assayed by crystal violet 1% and its growth measured by spectrophotometer. The saliva viscosity was analyzed by viscometer, and pH of saliva was measured by pH meter. Results: Based on the optical density values, growth of S. mutans in saliva ranged <300 CFU/mL (0.1 nm) at concentrations of 25%, 12.5% and 6.25% for 24 hours. Whereas at the 48 h and 72 h period of incubation shown an increase in growth of S. mutans ranged 300-600 CFU/mL (0.2-0.36 nm). The inhibitory biofilm formation of S. mutans in saliva was significantly higher at concentrations of 12.5% and 6.25% at 24 h incubation times on a moderate scale, whereas the histatin-5 was effective to inhibit S. mutans biofilm on the 50 and 25 ppm. The saliva possessed a higher inhibitory of biofilm S. mutans than histatin-5 and good level viscosity (0.91-0.92 cP). Conclusion: The saliva was able to control the growth of S. mutans, and histatin-5 can inhibit the biofilm formation S. mutans. Furthermore, the saliva was also able to respond to the pH change with good viscosity of saliva.

Can composition and preheating improve infiltrant characteristics and penetrability in demineralized enamel?

Abstract The composition of infiltrants can influence their physical properties, viscosity and depth of penetration (DP). Strategies are used to increase the DP, such as the addition of diluents or the use of heat. This study aimed to evaluate the effect of preheating and composition on physical properties and DP of infiltrants in demineralized enamel. The groups were assigned, and the following experimental formulations were made: 25%BisEMA +75%TEGDMA; 25%BisEMA +65%TEGDMA +10%ethanol; 25%BisEMA +65%TEGDMA +10%HEMA; 100%TEGDMA; 90%TEGDMA +10%ethanol; 90%TEGDMA +10%HEMA. The samples were photoactivated at two temperatures (25°C and 55°C). Degree of conversion (DC) was performed using an infrared spectrophotometer. Elastic modulus (E), flexural strength (FS) and contact angle (CA) tests were also performed. The DP of an infiltrant in demineralized enamel was determined by confocal laser scanning microscopy (CLSM) using an indirect labeling technique. The data were analyzed by two-way ANOVA and Tukey's test. DC increased after preheating in all the groups; however, 90%TEGDMA+10%ethanol showed the lowest DC for both temperatures, and the lowest E. Preheating did not influence E or FS. The CA increased at 55°C for most groups, but decreased for groups containing HEMA. Temperature did not seem to influence DP, and Icon showed the lowest DP values. The 100%TEGDMA composition showed more homogeneous penetration, whereas Icon showed heterogeneous and superficial penetration. The preheating technique does not improve all properties in all the material compositions. The composition of a material can influence and improve its properties.

Avaliação do escoamento de materiais de moldagem elastoméricos através do teste 'Shark-Fin' modificado / Analysis of flow profile of elastomeric impression materials using a modified 'Shark-Fin' Test

Materiais de impressão com boa fluidez são essenciais para a captura das margens dos preparos dentais. O objetivo deste estudo, para tanto, foi avaliar, por meio do dispositivo de teste 'shark-fin' (3M ESPE), o escoamento de dois materiais de moldagem elastoméricos, um poliéter (PE) e um polivinilsiloxano (PVS). Foi realizada uma modificação no teste 'shark-fin' de modo a permitir a aproximação do estudo in vitro à realidade clínica, avaliando o comportamento de duas viscosidades de cada material aplicadas em um tempo único. Um poliéter (PE) de alta (Impregum Penta Soft / 3M ESPE) e de baixa viscosidade (Impregum Garant L Duosoft / 3M ESPE), um polivinilsiloxano (PVS) de alta (Express XT Penta H / 3M ESPE), de média (Express XT Pasta Fluida de Média viscosidade / 3M ESPE) e de baixa viscosidade (Express XT Pasta Fluida de Baixa viscosidade / 3M ESPE) foram divididos em 21 grupos (n=5) e testados isoladamente e combinados em proporções de 1 : 1, nos tempos de trabalho de 50, 80 e 120 s. Após, as alturas das barbatanas formadas foram medidas com o auxílio de um paquímetro digital. A análise estatística dos resultados foi realizada por análise de variância (ANOVA) one-way seguida pelo teste LSD post hoc (p=0,05). Verificou-se que os valores das alturas das barbatanas diferiram significativamente entre os materiais e a cada intervalo de tempo (p<0,05). As barbatanas diminuíram para todos os grupos com o aumento do tempo de trabalho, exceto para o grupo PE de baixa viscosidade e PVS em múltiplas misturas (alta associada à baixa viscosidade e alta associada à média viscosidade). Todos os grupos de PE apresentaram valores mais altos para as barbatanas formadas em comparação aos grupos de PVS, tanto em uma viscosidade quanto em duas viscosidades associadas, durante todo o tempo de trabalho. O poliéter mostrou um melhor comportamento no que diz respeito ao escoamento quando comparado ao polivinilsiloxano. (AU)

Good flowable impression materials are needed to capture preparation margins. The aim of this study was to evaluate, through the 'shark-fin' test device (3M ESPE), the flow of two elastomeric impression materials, a polyether (PE) and a polyvinylsiloxane (PVS). The 'shark-fin' test was modified to convey the approximation of the in vitro study to the clinical application, assessing the behavior of two viscosities of each material applied at one point in time. A high viscosity polyether (PE) (Impregum Penta Soft / 3M ESPE) and a low viscosity (Impregum Garant L Duosoft / 3M ESPE), a high viscosity polyvinylsiloxane (PVS) (Express XT Penta H / 3M ESPE), a medium viscosity (Express XT Regular Body / 3M ESPE) and a low viscosity (Express XT Light Body / 3M ESPE) were divided into 21 groups (n=5) and tested solely, and in a layered mixture of 1 : 1 at working times of 50, 80 and 120 s. Afterwards, the fin heights were measured with a digital caliper. The statistical analysis was performed by one-way analysis of variance (ANOVA) and LSD post hoc test (p=0,05). It was found that the 'shark-fin' values differed significantly among materials and at each time interval (p<0,05). The fin heights decreased for all groups with increasing of working time, except for the low viscosity PE and PVS in multiple mixtures (high with low viscosity and high with medium viscosity). The PE groups showed the highest 'shark-fins' compared to PVS, both in single and multiple mixtures, during the entire working time. The polyether impression materials had a better flow profile compared to polyvinylsiloxane groups. (AU)

Influência do tipo de agente espessante e da viscosidade nas propriedades do gel clareador a base de peróxido de hidrogênio / Influence of thickener kind and hydrogen peroxide gel viscosity on the properties of the hydrogen peroxide gel

O estudo avaliou como o agente espessante e a viscosidade de um gel de peróxido de hidrogênio a 35%, podem influenciar o efeito clareador e as reações químicas que ocorrem dentro da camada de gel. Foram utilizados 540 dentes incisivos bovinos, dos quais 270 foram designados para obtenção de discos de esmalte e dentina para análise da cor. Os outros 270 dentes foram usados para as mensurações realizadas no gel. Géis clareadores experimentais (peróxido de hidrogênio 35% e pH 6.5) foram preparados com cinco agentes espessantes (CAR­ Carbopol; SA­ Salcare, ARI­ Aristoflex, CMC­ Carboximetilcelulose, AER­ Aerosil), para a obtenção de géis com viscosidades baixa (B - 50.000 cP), média (M - 250.000 cP) e alta (A ­ 1.000.000 cP). Além disso, três grupos controle foram preparados: CP (Controle positivo) - solução de peróxido sem espessante, CC (Controle comercial) - Whiteness HP (FGM); CN (Controle negativo) ­ água ultrapura. Os géis foram aplicados sobre o esmalte por 45 min. Foi avaliada a mudança de cor dos dentes, alterações na concentração de peróxido, pH e concentração de radicais livres. Os dados dos grupos experimentais foram analisados estatisticamente com ANOVA a 2 fatores (ESPESSANTE x VISCOSIDADE) e teste de Tukey. A comparação com os grupos controle foi realizada com o teste de Dunnett (a = 5%). Para todas as mensurações realizadas, a ANOVA mostrou diferenças significativas para os dois fatores (p <0,05). Para a mudança de cor (ΔE*ab), os resultado do teste de Tukey foram: ESPESSANTE - CMC 2.80(0.78)a, SA 2.81(0.8)a, AER 3.13(0.8)ab, CAR 3.24(1.05)ab, ARI 3.32(0.89)b; VISCOSIDADE - A 2.90(0.78)a, M 3.02(0.84)b, B 3.27(1.0)c. Para a concentração de peróxido os resultados foram: ESPESSANTE - CMC -4.86(1.85)a, AER -3.79(1.36)b, SA - 3.53(0.74)b, ARI -3.48(1.21)b, CAR -2.5(1.40)c; VISCOSIDADE - A -4.41(2.16)a, M - 3.26(0.91)b, B -3.23(0.92)b. Para o pH os resultados foram: ESPESSANTE - SA - 13.87(3.05)a, CAR -12.62(2.72)b, ARI -5.82(2.41)c, AER -4.94(1.42)d, CMC - 4.43(1.68)e; VISCOSIDADE - A -9.22(5.82)a, M -8.8(4.88)b, B -6.99(2.34)c. Para os radicais livres, os resultados foram: ESPESSANTE - SA 4.93a, CAR 6.83b, ARI 10.88c, AER 16.48d, CMC 29.76e; VISCOSIDADE - A 11.27a, M 13.82b, B 16.24c. A diferença significativa entre CN e os géis experimentais mostram a validação da metodologia e a eficiência do efeito clareador observado. A semelhança entre CC e géis experimentais demostram a capacidade de clareamento esperada para tal produto. Mediante esses resultados, podemos concluir que: o tipo de agente espessante e a viscosidade do gel clareador influenciam significativamente na interação do produto com o substrato dental e consequentemente na alteração de cor(AU)

The study evaluated how the thickening agent and the viscosity of a 35% hydrogen peroxide gel can influence the chemical reactions occurring inside the gel layer. 540 bovine incisors were used, from which 270 were used for color evaluation. The other 270 bovine incisors were used for gel changing evaluation. Experimental bleaching gels (hydrogen peroxide 35% and pH 6.5) were prepared using five thickening agents (CAR­ Carbopol; SA­ Salcare, ARI­ Aristoflex, CMC­ Carboxymethylcellulose, AER­ Aerosil), which were added to produce gels with low (L - 50.000 cP), medium (M - 250.000 cP) and high (H ­ 1.000.000 cP) viscosities. In addition, three control groups were prepared: PC (Positive Control) ­ a hydrogen peroxide solution; CC (Commercial Control) ­ Whiteness HP, FGM; NC (Negative Control) ­ purified water. The bleaching gels were applied for 45 minutes over the specimens. The evaluation were performed for color change, and concentration change of peroxide, pH and free radicals. Data were statistically analyzed with two-way ANOVA (THICKNER AND VISCOSITY) and Tukey Test. For control groups comparison Dunnett test was used ( = 5%). Significant differences were observed for both factors for all measurements performed (p <0,05). For color change (ΔE*ab) Tukey Test results were: THICKNER - CMC 2.80(0.78)a , SA 2.81(0.8)a , AER 3.13(0.8)ab, CAR 3.24(1.05)ab, ARI 3.32(0.89)b ; VISCOSITY - H 2.90(0.78)a , M 3.02(0.84)b , L 3.27(1.0)c . The results for peroxide concentration for THICKNER - CMC -4.86(1.85)a , AER -3.79(1.36)b , SA -3.53(0.74)b , ARI -3.48(1.21)b , CAR -2.5(1.40)c ; VISCOSITY - H -4.41(2.16)a , M -3.26(0.91)b , L -3.23(0.92)b . The results for pH for THICKNER - SA -13.87(3.05)a , CAR -12.62(2.72)b , ARI -5.82(2.41)c , AER -4.94(1.42)d , CMC -4.43(1.68)e ; VISCOSITY - H -9.22(5.82)a , M -8.8(4.88)b , L - 6.99(2.34)c . The results for free radicals for THICKNER - SA 4.93a , CAR 6.83b , ARI 10.88c , AER 16.48d , CMC 29.76e ; VISCOSITY - H 11.27a , M 13.82b , L 16.24c . The difference between NC and experimental groups certify the methods used and the efficiency of bleaching results. The similarity between CC and experimental groups results demonstrate the achievement of the expected bleaching result. Based on the results, it can be concluded that: The thickening agent and the gel viscosity significantly influence the product interaction with the dental structure and consequently on dental color(AU) ,

Does low-cost GIC have the same survival rate as high-viscosity GIC in atraumatic restorative treatments? A RCT

Abstract Atraumatic Restorative Treatment (ART) is one of the strategies used to control dental caries; it involves hand instruments for removal of carious tissue, and restorations using high-viscosity Glass Ionomer Cement (GIC). The present controlled clinical trial aimed to evaluate the performance of low-cost GIC indicated for ART in primary teeth, compared with high-viscosity GIC, after one year of follow-up. Two-to six-year-old children with dentin caries lesions on one or two surfaces of anterior and posterior teeth were selected. The children were randomly assigned to 2 groups according to the restorative material used: G1 (control) - Ketac Molar®; G2 (experimental) - Vitro Molar®. Treatments were performed in a school setting, following the guidelines of the ART. A total of 728 restorations were performed in 243 children. Descriptive analysis and Poisson regression were applied, with a significance level of p < 0.05. After 12 months, 559 (76.8%) restorations were re-evaluated. The success rate was evaluated by the prevalence ratio (PR), associated with restorations performed in primary second molars (PR = 1.21; 95%CI = 1.03-1.42), and with small (PR = 1.35; 95%CI = 1.14-1.60) or medium cavities (PR = 1.29; 95%CI = 1.08-1.55), using Ketac Molar® material (PR= 1.07; 95%CI = 1.01-1.15), considering p < 0.05. Small or medium restorations in primary second molars performed with high-viscosity GIC (Ketac Molar®) were more successful than restorations performed with low-cost GIC indicated for ART.

Desenvolvimento e caracterização de formulação de hipoclorito de sódio em gel para uso endodôntico / Development and characterization of sodium hypochlorite gel formulation for endodontic use

A presente pesquisa dedicou-se ao desenvolvimento e à caracterização de uma formulação em gel para o NaOCl, que permitisse o maior controle dessa substância durante a irrigação do sistema de canais radiculares sem perder as características que o tornam um agente de limpeza e descontaminação tão eficiente. Foi utilizada uma solução concentrada de NaOCl, a qual foi titulada para determinação do teor de cloro ativo, e um tensoativo, o lauril éter sulfato de sódio, para o qual foi calculada a concentração micelar crítica em água destilada. A partir destes reagentes foram realizadas diluições e manipuladas sete formulações de NaOCl a 2,5% com diferentes concentrações do tensoativo, as quais foram submetidas às análises de pH, tensão superficial, espectroscopia de infravermelho com transformada de Fourier (FTIR), molhabilidade em dentina humana, reologia, potencial antibacteriano contra Enterococcus faecalis e capacidade de dissolução tecidual. Os valores de pH demonstraram que a adição do tensoativo não alterou este parâmetro, mantendo o meio alcalino desejável para a ação do NaOCl. A adição do tensoativo reduziu a tensão superficial em mais de 50% em relação à solução aquosa de NaOCl. A caracterização por FTIR demonstrou que os reagentes das formulações apenas se solubilizam e interagem, não implicando a ocorrência de reação química entre elas. A molhabilidade das formulações sobre a dentina humana foi inferior à medida para a solução de NaOCl. Todas as formulações apresentaram viscosidade e aspecto que permitem a utilização clínica de forma satisfatória. O teste microbiológico de disco-difusão em ágar revelou ação satisfatória e similar à solução aquosa de NaOCl 2,5%. A velocidade de dissolução tecidual foi reduzida pela adição do tensoativo. Concluiu-se que as formulações de NaOCl em gel com o lauril éter sulfato de sódio são promissoras para sua utilização como substâncias químicas auxiliares em Endodontia (AU).

This research focused on the development and characterization of a gel formulation for NaOCl, which allows greater control during the root canals irrigation without losing the characteristics that make it such na efficient cleaning and decontamination agent. It was used a concentrated solution of NaOCl, which was titrated to determine the active chlorine content, and a surfactant, sodium lauryl ether sulfate, for which the critical micellar concentration in distilled water was calculated. From these reagents were carried out dilutions and manipulated seven formulations of 2.5% NaOCl with different surfactant concentrations, which were submitted to the following analysis: pH, surface tension, Fourier transform infrared spectroscopy (FTIR), wettability on human dentin, rheology and antibacterial potential against Enterococcus faecalis. The pH values showed that the addition of the surfactant did not alter this parameter, keeping the alkaline medium desirable for NaOCl action. The surfactant addition reduced surface tension by more than 50% relative to the NaOCl aqueous solution. The FTIR showed that the reagents only solubilize and interact, not implying the occurrence of chemical reaction between them. The wettability on human dentin was lower than that measured for the NaOCl solution. All formulations showed viscosity and appearance that allow clinical use satisfactorily. The microbiological disk-diffusion test on agar showed a satisfactory action similar to the 2.5% aqueous NaOCl solution. The ability of tissue dissolution was reduced by the addition of the surfactant. It was concluded that NaOCl gel formulations with sodium lauryl ether sulfate are promising for their use as endodontic auxiliary chemicals (AU).

Influência do tipo de agente espessante e da viscosidade do gel de peróxido de hidrogênio na eficácia clareadora e microdureza do esmalte dental / Influence of the type the thickening agent and viscosity of hydrogen peroxide gel on dental bleaching efficacy and microhardness of dental enamel

O objetivo deste estudo foi avaliar a influência do tipo de agente espessante e da viscosidade do gel de peróxido de hidrogênio (PH) a 35%, na eficácia clareadora e microdureza do esmalte dental. Além disso, a decomposição da molécula de peróxido de hidrogênio dentro do gel clareador também foi verificada. Foram utilizados 110 dentes incisivos bovinos dos quais foram obtidos 324 espécimes em forma de discos de esmaltedentina, com 4mm de diâmetro, utilizando-se broca trefina. A leitura da cor dos referidos espécimes foi realizada em um espectrofotômetro de reflectância, enquanto a microdureza do esmalte foi analisada através de um microdurômetro com indentador Knoop. Para verificação da concentração de peróxido foi utilizado o método de titulação utilizando o permanganato de potássio. Géis clareadores experimentais foram preparados, contendo cinco diferentes tipos de agentes espessantes (Ar - Aristoflex ­ Clariant, Ca - Carbopol 980 ­ Lubrizol, CMC ­ Carboximetilcelulose, Ae ­ Aerosil 200 - Evonik e Sa - Salcare ­ BASF), os quais foram adicionados em quantidades suficientes para produzir géis com viscosidades baixa (B - 50.000 cPs), média (M - 250.000 cPs) e alta (A ­ 1.000.000 cPs). Os espécimes foram divididos em dezoito grupos: CP (Controle positivo) - de peróxido sem adição de agente espessante, CN (Controle Negativo) ­água ultra pura, CC (Controle Comercial) ­ gel de PH a 35% Whiteness HP-FGM, Ar/B, Ar/M, Ar/A; Ca/B, Ca/M e Ca/A; CMC/B, CMC/M, CMC/A, Ae/B, Ae/M, Ae/A, Sa/B, Sa/M e Sa/A. Os agentes clareadores foram aplicados sobre a superfície do esmalte por um total de 60 minutos. A cada 20 minutos, o agente clareador era trocado e uma amostra deste era coletada e as concentrações de peróxido de hidrogênio mensuradas. A microdureza do esmalte foi avaliada imediatamente após, sendo então as amostras imersas em saliva artificial por 7 dias, seguido pela leitura final da cor. Os dados foram analisados estatisticamente, empregando um nível de significância de 5%. Quanto ao percentual de redução da microdureza a ANOVA 2 fatores mostrou diferenças significativas para o tipo de espessante e viscosidade. Os resultados do testede Tukey foram: espessante ­ Ae 11,73(3,98)a, As 14,71(3,79)b, CMC 17,00(4,01)c, Ar 22,13(4,43)d e Ca 28,06(2,59); viscosidade ­ alta 15,39(8,52)a, média 18,56(5,42)b e baixa 22,22(4,40)c. Quanto ao DEab e DE00 não mostrou diferenças significativas. Com relação à concentração do peróxido de hidrogênio, as maiores reduções occorreram para o espessante Salcare. Concluiu-se que o tipo de espessante e viscosidade dos géis não influenciaram o efeito clareador, porém influenciaram na microdureza do esmalte. O tipo de espessante e viscosidade também influenciaram a concentração final do peróxido de hidrogênio, e o espessante. Sa apresentou o maior percentual de redução de peróxido. Todos os grupos apresentaram diferenças significativas e relação ao grupo CN. O grupo CA/A não apresentou diferença significativa em relação ao grupo CP e apenas o grupo Sa/M não apresentou diferença significativa em relação ao grupo CC(AU)

The aim of this study was to evaluate of the type of the agent thickener and viscosity of 35% hydrogen peroxide gel, in the bleaching efficacy and microhardness of dental enamel. In addition, the decomposition of the hydrogen peroxide molecule within the bleaching gel was also verified. We used 110 bovine incisor teeth of which 324 specimens were obtained in the form of enamel-dentin discs, with 4 mm diameter, using a trefin drill. The color reading of the aforementioned specimens was performed in a reflectance spectrophotometer, while the microhardness of the enamel was analyzed through a microdurometer with Knoop indenter. To verify the peroxide concentration, the titration method was used using potassium permanganate 0,1 N. Experimental bleaching gels were prepared, containing five different types of thickened agents (Ar ­ Aristoflex ­ Clariant, Ca ­ Carbopol 980 ­ Lubrizol, CMC ­ Carboxymethylcellulose, Ae ­ Aerosil 200 ­ Evonik and Sa ­ Salcare ­ BASF), which were added in sufficient quantities to produce gels with low viscosities (L ­ 50.000 cPs), Medium (M ­ 250.000 cPs) and High (H ­ 1.000.000 cPs). The specimens were divided into eighteen groups/subgroups: PC (positive control) ­ was applied a peroxide solution without adding thickened agent, NC (Negative control) ­ was applied ultrapure water, CC (Comercial control) and fifteen more groups, containing hydrogen peroxide at 35% associated with a specific thickened agent, in different viscosities, these being: Ar/L, Ar/Mand Ar/H (Aristoflex in low, medium and high viscosity); Ca/L, Ca/M and Ca/H (Carbopol in low, medium and high viscosity); CMC/L, CMC/M and CMC/H (Carboxymethylcellulose in low, medium and high viscosity); Ae/L, Ae/M and Ae/H medium and high viscosity). The bleaching agents were applied on the enamel surface for 60 minutes. Every 20 minutes, the bleaching agent was changed and a sample was collected and the hydrogen peroxide concentrations measued. The enamel microhardness was immersed in artificial saliva for 7 days, followed by the final color reading. Data were analyzed statistically, employing a significance level of 5%. Regarding the percentage of microhardness reduction the ANOVA 2 factors showed significant differences for the type of thickener and viscosity. The Tukey test results were: thickener ­ Ae 11.73(3,98)a, As 14.71(3.79)b, CMC 17.00(4.01)c, Ar 22.13(4.43) and Ca 28.06(2.59); viscosity ­ high 15.39(8.52)a, average 18.56(5.42)b and low 22.22(4.40)c. Regarding DEab and DE00 showed no significant differences. Regarding the concentration of hydrogen peroxide, the greatest reductions occurred for the Salcare thickener. It was concluded that the type of thickener and viscosity of the gels did not influence the bleaching effect, but influence the microhardness of the enamel. The type of thickener and viscosity also influenced the final concentration of hydrogen peroxide, and the thickener. Sa presented the highest percentage of peroxide reduction. All groups presented significant difference in relation to the CP group and only the Sa/M group did not present a significant difference in relation to the CC group(AU)

Study of the chemical interaction between a high-viscosity glass ionomer cement and dentin

Abstract Objective To investigate the chemical interactions between a high-viscosity glass ionomer cement (GIC) (KetacTM Molar Easymix, 3M ESPE, Seefeld, Bavaria, Germany) and human dentin. It was also analyzed the dynamics of GIC setting mechanism based on the time intervals required for the GIC and the GIC mixed with dentin to achieve stability. Material and Methods Each constituent of GIC - powder (P) and liquid (L) - and powdered dentin (D), as well as the associations P+L, D+L, and P+L+D in the concentrations of 29%, 50%, 65%, 78%, 82%, and 92% of GIC were analyzed with Fourier transform infrared (FTIR) and Raman spectroscopy. Results New optical absorption bands and/or Raman bands, which were not present in P, L, or D, were observed in the associations. The concentrations of 29% and 50% of GIC showed higher interaction, revealing that the amount of dentin influences the formation of new optical absorption or scattering bands. FTIR bands showed that the setting time to achieve bond stability was longer for the high-viscosity GIC (38±7 min) than for the sample with 29% of GIC (28±4 min). Conclusions The analysis revealed the formation of new compounds or molecular rearrangements resulting from the chemical interactions between GIC and dentin. Moreover, this study provides an effective method to evaluate the dynamics of the setting mechanism of GICs.

Effect of different composite core materials on fracture resistance of endodontically treated teeth restored with FRC posts

Abstract Objective This study evaluated the fracture resistance of endodontically treated teeth restored with fiber reinforced composite posts, using three resin composite core build-up materials, (Clearfil Photo Core (CPC), MultiCore Flow (MCF), and LuxaCore Z-Dual (LCZ)), and a nanohybrid composite, (Tetric N-Ceram (TNC)). Material and Methods Forty endodontically treated lower first premolars were restored with quartz fiber posts (D.T. Light-Post) cemented with resin cement (Panavia F2.0). Samples were randomly divided into four groups (n=10). Each group was built-up with one of the four core materials following its manufacturers’ instructions. The teeth were embedded in acrylic resin blocks. Nickel-Chromium crowns were fixed on the specimens with resin cement. The fracture resistance was determined using a universal testing machine with a crosshead speed of 1 mm/min at 1350 to the tooth axis until failure occurred. All core materials used in the study were subjected to test for the flexural modulus according to ISO 4049:2009. Results One-way ANOVA and Bonferroni multiple comparisons test indicated that the fracture resistance was higher in the groups with CPC and MCF, which presented no statistically significant difference (p>0.05), but was significantly higher than in those with LCZ and TNC (p<0.05). In terms of the flexural modulus, the ranking from the highest values of the materials was aligned with the same tendency of fracture loads. Conclusion Among the cores used in this study, the composite core with high filler content tended to enhance fracture thresholds of teeth restored with fiber posts more than others.

Avaliação dos parâmetros salivares e dos compostos sulfurados voláteis dos pacientes com câncer em cabeça e pescoço, durante o tratamento concológico / Evaluation of salivary parameters and volatile sulfur compounds of patients with head and neck cancer, during oncological treatment

OBJETIVO: O objetivo deste trabalho foi investigar as alterações dos parâmetros salivares e dos níveis dos compostos sulfurados voláteis(CSV), durante o tratamento oncológico, em pacientes com carcinoma espinocelular em cabeça e pescoço. MATERIAIS E MÉTODOS: Estudo clínico de segmento, em que 24 pacientes foram examinados em dois momentos: antes de iniciar o tratamento com radioterapia e quimioterapia e após o término das 39 sessões de radioterapia. Avaliação da presença de saburra lingual foi realizada durante o exame clínico. Os parâmetros salivares avaliados foram: fluxo salivar em repousoe estimulado os quais foram coletadas durante 05 minutos em um tubo Falcommilimetrado. Para a saliva estimulada utilizou-se o hiperboloide (instrumento de mastigação); a viscosidade pelo viscosímetro de Ostwald modificado (modelo Cannon-FrenskeRoutine); o pH foi mensurado com um pH metro digital portátil (model Checker® 1 - HI98103). A avaliação dos CSV foi feita pelo método da cromatografia gasosa utilizando Oral ChromaTM. A escala EVA foi registrada em valores de zero a dez, em relação à sensação da boca seca do paciente.Os resultados foram analisados por meio do programa SPSS versão 17.0, com nível de confiança de 95%. RESULTADOS:Os resultados mostraram que houve uma redução estatisticamente significante do fluxo salivar estimulado e em repouso (p= 0,0002 e p= 0,0005 respectivamente) e do pH (p=0,0151). Observou-se aumento significativo da viscosidade após o término do tratamento(p= 0,0420) e também um aumento da xerostomia (p <0,0001). As concentrações dos CSV não sofreram alterações ao final do tratamento. CONCLUSÃO:Estes resultados demonstraram que o tratamento oncológico provoca uma redução do fluxo salivar e do pH, aumento da viscosidade e da xerostomia. As concentrações dos CSV não sofreram alterações ao final do tratamento, mesmo ocorrendo as alterações dos parâmetros salivares

OBJECTIVE: The aim of this study was to investigate changes in salivary parameters and levels of volatile sulfur compounds (VSC) during the oncological treatment in patients with squamous cell carcinoma of the head and neck. MATERIALS AND METHODS:clinical study segmentedin which 24 patients were examined in two stages: before starting treatment with radiotherapy and chemotherapy and after the end of the 39 radiotherapy sessions. Evaluation of the presence of tongue coating was performed during clinical examination. The salivary evaluated parameters were: salivary flow at unstimulated and stimulated which were collected during 05 minutes in a graph Falcon tube. For the stimulated saliva used the hyperboloid (chewing instrument); the viscosity by viscometer Ostwald modified (Cannon-FrenskeRoutine model); pH was measured with a portable digital pH meter (model Checker® 1 - HI98103). The evaluation was made by the CSV method of gas chromatography using Oral ChromaTM. The VAS scale was recorded at values from zero to ten, with the sensation of dry mouth patients. The results were analyzed using SPSS version 17.0 with 95% confidence level. RESULTS: The results showed a statistically significant reduction in salivary flow stimulated and unstimulated (p = 0.0002 and p = 0.0005 respectively) and pH (p = 0.0151). A significant increase in viscosity after the treatment (p = 0.0420) and an increase of xerostomia (p <0.0001). The CSV concentrations did not change after treatment. CONCLUSION: These results demonstrate that cancer treatment causes a reduced salivary flow and pH, increased viscosity and xerostomia. The CSV concentrations did not change after treatment, even occurring changes in salivary parameters

Effects of calcium hydroxide addition on the physical and chemical properties of a calcium silicate-based sealer

Recently, various calcium silicate-based sealers have been introduced for use in root canal filling. The MTA Fillapex is one of these sealers, but some of its physicochemical properties are not in accordance with the ISO requirements. Objective: The aim of this study was to evaluate the flowability, pH level and calcium release of pure MTA Fillapex (MTAF) or containing 5% (MTAF5) or 10% (MTAF10) calcium hydroxide (CH), in weight, in comparison with AH Plus sealer. Material and Methods: The flowability test was performed according to the ISO 6876:2001 requirements. For the pH level and calcium ion release analyses, the sealers were placed individually (n=10) in plastic tubes and immersed in deionized water. After 24 hours, 7 and 14 days, the water in which each specimen had been immersed was evaluated to determine the pH level changes and calcium released. Flowability, pH level and calcium release data were analyzed statistically by the ANOVA test (α=5%). Results: In relation to flowability: MTAF>AH Plus>MTAF5>MTAF10. In relation to the pH level, for 24 h: MTAF5=MTAF10=MTAF>AH Plus; for 7 and 14 days: MTAF5=MTAF10>MTAF>AH Plus. For the calcium release, for all periods: MTAF>MTAF5=MTAF10>AH Plus. Conclusions: The addition of 5% CH to the MTA Fillapex (in weight) is an alternative to reduce the high flowability presented by the sealer, without interfering in its alkalization potential. .

Influência de polímeros bioadesivos sobre o efeito protetor do flúor no desenvolvimento da erosão dental / Influence of polymers bioadhesive on the protective effect of fluoride over enamel erosion development

A erosão é um processo multifatorial que envolve a desmineralização dental pela ação química de ácidos extrínsecos ou intrínsecos. Visto que o efeito protetor do flúor contra erosão tem sido relacionado principalmente à formação de depósitos de fluoreto de cálcio e à adsorção de íons flúor na superfície dental, hipotetizou-se que a incorporação de agentes bioadesivos nas soluções fluoretadas poderia aumentar a interação de flúor aos tecidos e, consequentemente, potencializar seu efeito protetor. Neste estudo foram testados três polímeros (Carbopol 980, Carboximetil Celulose e Aristoflex AVC), em concentrações pré-determinadas com base na viscosidade da solução a ser utilizada, que simularam um enxaguatório bucal. Amostras de esmalte bovino foram confeccionadas e submetidas a um modelo de desmineralização e remineralização com imersão em ácido cítrico a 0,3%, pH 2,6, tratamentos com as soluções contendo os polímeros associados ou não ao fluoreto de sódio (900 ppm) e imersão em saliva artificial. Foram realizadas medidas de microdureza Knoop (KHN1) e análise perfilométrica inicial de todos os espécimes. Após o primeiro desafio ácido, foi realizada novamente leitura da microdureza dos espécimes (KHN2), bem como após a primeira imersão nas soluções de tratamento (KHN3) e o segundo desafio ácido (KHN4), caracterizando a avaliação da erosão inicial. A alteração de percentual de remineralização (% rem = (KHN3-KHN2/KHN2)*100) e de proteção (% prot = (KHN4-KHN2/KHN2)*100) foram determinadas. A ciclagem des-re foi repetida por cinco dias, 6x/dia, com imersão nas soluções de tratamento após a primeira e última imersão diária em ácido. Ao final do experimento, a análise perfilométrica final foi realizada para mensurar a perda de estrutura de esmalte, comparando-se a altura dos perfis inicial e final. Os dados foram analisados com o teste estatístico ANOVA e teste de Tukey (p < 0,05). Nenhum polímero isolado apresentou propriedades de remineralização, apenas o Carbopol, ...

Dental erosion is a multifactorial process involving tooth demineralization by the chemical action of intrinsic and extrinsic acids. Since the protective effect of fluoride against erosion has been mainly related to fluoride adsorption and calcium fluoride deposits on tooth surface, it was hypothesized that the incorporation of bioadhesive polymers in fluoridated solutions would increase fluoride interaction with the enamel surface, and consequently, enhance its protective effect. In this study, three polymers were tested (Carbopol 980, Carboxymethyl Cellulose and Aristoflex AVC), in pretested concentrations based on the viscosity of the solutions to be used, which simulated a mouthrinse. Bovine enamel specimens were prepared and submitted to a demineralization-remineralization model with immersion in 0.3% citric acid, treatment with polymers solution associated or not to sodium fluoride (900 ppm), and storage in artificial saliva. Initial Knoop hardness (KHN1) and profilometry of all specimens were measured. After the first acid challenge, microhardness were measured again (KHN2), as well as after the first immersion in treatment solutions (KHN3) and after the second acid challenge (KHN4), characterizing the initial erosion analysis. Percentage of remineralization (%rem=KHN3-KHN2/KHN2*100) and of protection (%prot=(KHN4-KHN2/KHN2*100) was determined. The demineralization-remineralization cycling was repeated for five days, 6x/day, with immersion in treatment solutions after the first and last acid immersion of the day. At the end of the experiment, enamel loss was assessed with profilometry, by comparison of the initial and final profiles. Data were analyzed with ANOVA an Tukey´s tests (p < 0.05). Regarding rehardening properties, no polymer isolated differed from control. When associated to NaF, Carbopol presented similar %rem compared to NaF control. For initial erosion protection, the polymers isolated did not significantly reduce ...

Análise do ph e viscosidade salivar e sua correlação com a doença periodontal – estudo piloto / Analysis of pH and viscosity of saliva and its correlation with periodontal disease - Pilot Study

Objetivo: comparar a viscosidade e o pH da saliva de portadores e não portadores de doença periodontal e verificar se há correlação entre pH e viscosidade salivar. Método: Realizou-se estudo caso-controle em que um total de 34 pacientes foram alocados equitativamente em 2 grupos. Coletou-se saliva total estimulada por meio de mastigação bilateral de garrote de silicone estéril. A mesma foi depositada em copo plástico descartável e imediatamente mergulhou-se, durante 30 segundos, o bulbo sensor do medidor de pH digital na saliva coletada. Para avaliação da viscosidade salivar utilizou-se viscosímetro de Ostwald modificado, modelo Cannon-Fenske Routine, tamanho 350. Valores menores que 1,5 centipoise (cp) foram considerados não viscosos, enquanto que para saliva viscosa considerou-se valores iguais ou maiores que 1,5 cp. Resultado: A mediana (intervalo interquartil) da viscosidade salivar dos portadores de doença periodontal foi 1,7 (1,4 a 3,4), enquanto que a do grupo controle foi 1,2 (1,1 a 1,3) cp (p<0,001). O pH salivar médio (intervalo de confiança de 95%) dos portadores e não portadores de doença periodontal foi 7,4 (7,2 a 7,6) e 7,2 (7,0 a 7,3), respectivamente (p = 0,04). Entretanto, a viscosidade salivar não se correlacionou com o pH salivar (rs = 0,05; p=0,7). Conclusão: A viscosidade da saliva de portadores de doença periodontal é maior do que a viscosidade da saliva de não portadores de doença periodontal

Objective: To compare the viscosity and pH of the saliva of subjects with and without periodontal disease and check for correlation between salivary pH and viscosity. Method: We conducted a case-control study in which a total of 34 patients were allocated equally into 2 groups. It was collected stimulated whole saliva by bilateral chewing of silicone sterile tourniquet. The saliva was deposited into a disposable plastic cup and immediately the bulb sensor of a digital pH meter was sank for 30 seconds in the collected saliva. For evaluation of salivary viscosity it was used a modified Ostwald viscometer, Model Cannon - Fenske Routine, size 350. Values less than 1.5 centipoise (cp) were considered non-viscous, whereas for viscous saliva it was considered values equal to or greater than 1.5 cp. Results: The median (interquartile range) viscosity saliva of patients with periodontal disease was 1.7 (1.4 to 3.4), while the control group was 1.2 (1.1 to 1.3) cp (p < 0.001). Salivary pH mean (confidence interval 95 %) of carriers and non-carriers of periodontal disease was 7.4 (7.2 to 7.6) and 7.2 (7.0 to 7.3), respectively (p = 0.04). However, the viscosity of saliva did not correlate with salivary pH (rs = 0.05, p =0.7). Conclusion: The viscosity of the saliva of patients with periodontal disease is greater than the viscosity of the saliva of non-periodontal disease subjects

The effect of viscosity and activation mode on biaxial flexure strength and modulus of dual resin cements / Efeito da viscosidade e modo de ativação na resistência flexural biaxial e módulo em cimentos resinosos duais

PURPOSE: The aim of this study was to evaluate the effects of curing mode and viscosity on the biaxial flexural strength (FS) and modulus (FM) of dual resin cements. METHODS: Eight experimental groups were created (n=12) according to the dual-cured resin cements (Nexus 2/Kerr Corp. and Variolink II/IvoclarVivadent), curing modes (dual or self-cure), and viscosities (low and high). Forty-eight cement discs of each product (0.5 mm thick by 6.0 mm diameter) were fabricated. Half specimens were light - activated for 40 seconds and half were allowed to self-cure. After 10 days, the biaxial flexure test was performed using a universal testing machine (1.27 mm/min, Instron 5844). Data were statistically analyzed by three-way ANOVA and Tukey's test (5%). RESULTS: Light-activation increased FS and FM of resin cements at both viscosities in comparison with self-curing mode. The high viscosity version of light-activated resin cements exhibited higher FS than low viscosity versions. The viscosity of resin and the type of cement did not influence the FM. Light-activation of dual-polymerizing resin cements provided higher FS and FM for both resin cements and viscosities. CONCLUSION: The use of different resin cements with different viscosities may change the biomechanical behavior of these luting materials.

OBJETIVO: O objetivo do estudo é avaliar o efeito do modo de ativação na resistência flexual biaxial (RF) e módulo (MF) em cimentos resinosos duais. METODOLOGIA: Foram formados oito grupos experientais (n=12) de acordo com cimento resinos (Nexus 2/Kerr Corp. and Variolink II/IvoclarVivadent), modo de ativação (dual ou auto-polimerizado) e viscosidade (baixa e alta). Quarenta e oito discos de cada cimento foram fabridados (0,5 mm espessura por 6,0 mm diametro). Metade dos espécimes foram foto-ativados e a outra metade foi deixado para auto-polimerização. Após dez dias, o teste biaxial foi realizado em máquina de ensaio universal (1,27 mm/min, Instron 5844). Os dados foram analisados estatisticamente por ANOVA e teste Tukey (5%). RESULTADOS: A foto-ativação aumentou a RF e RM para os cimentos em ambas as viscosidades em comparação com os grupos auto-polimerizados. A versão alta viscosidade dos cimentos foto-ativados apresentou maior RF que os cimentos em baixa viscosidade. A viscosidade e o tipo de cimento não influenciam o MF. A foto-ativação aumenta os valores de RF e MF para ambos os cimentos e viscosidades. CONCLUSÃO: O uso de diferentes cimentos com diferentes viscosidades pode influenciar o comportamento biomecânico de cimentos resinoso.

Avaliação da concentração de flúor, do pH, da viscosidade e do teor de sólidos solúveis totais em enxaguatórios bucais fluoretados disponíveis comercialmente na cidade de Manaus - AM / Analysis of fluoride concentration, pH, viscosity and the total soluble solids content of commercially available fluoride mouthrinses in the city of Manaus - AM

Objetivo: Avaliar a concentração de fluoretos, o pH, a viscosidade e o teor de sólidos solúveis totais (SST) de enxaguatórios bucais fluoretados disponíveis comercialmente na cidade de Manaus - AM. Método: Foram selecionadas aleatoriamente seis marcas de enxaguatórios bucais fluoretados, adquiridos em drogarias da cidade de Manaus em triplicata, com lotes diferentes. A análise da concentração de flúor e do pH foi realizada mediante o uso do analisador de íons ORION 720A, enquanto na determinação da viscosidade foi utilizado um viscosímetro AVS - 350 (Schott), em temperaturas de 20 e 37ºC e o teor de sólidos solúveis totais (SST) foi determinado por meio da leitura da refratometria na escala °Brix. Os dados foram submetidos à análise de variância de ANOVA e ao teste de Tukey para demonstrar diferenças estatisticamente significantes entre os enxaguatórios e os seus respectivos lotes. Resultados: A concentração de flúor encontrada nos enxaguatórios analisados variou entre 213,22 e 249,78 ppm, enquanto o pH da maioria dos enxaguatórios mostrou-se ácido, mas apenas duas marcas apresentaram-se potencialmente erosivas, com pH inferior a 5,5. A viscosidade a 20:C apresentou um intervalo de 1,28 - 2,56 mm²/s e quando a 37 ºC, um intervalo de 1,02 e 1,90 mm²/s. O teor de SST variou entre 7 e 22,50% na escala ºBrix. Conclusão: Dentre os produtos testados, o Colgate Plax® Kids apresentou elevado índice de Teor de Sólidos Solúveis Totais (ºBrix), de viscosidade e pH endógeno abaixo do considerado crítico.

Objective: To assess the concentration of fluoride, pH, viscosity and the total soluble solids (SST) content of commercially available fluoride mouthrinses in the city of Manaus - AM. Method: Six brands of fluoridated mouthrinses were randomly selected in triplicate. For each medicine, the average of these three evaluations was considered for statistical analysis.The analysis of the fluoride concentration and pH was performed using the Orion 720A ion analyzer, while to determine viscosity the viscometer AVS - 350 (Schott) was used at temperatures of 20 ºC and 37 ºC and total soluble solids content (TSSC) was determined by reading the Brix scale refractometer. Data were subjected to analysis of variance ANOVA and Tukey test to demonstrate statistically significant differences between the mouthrinses and their respective lots. Results: The fluoride concentration found in mouthrinses analyzed varied between 213.22 and 249.78 ppm, while the pH of most mouthrinses showed to be acid, but only two brands were potentially erosive, with a pH below 5.5. Viscosity at 20°C showed an interval from 1.28 to 2.56 mm²/s, and when at 37 ºC, an interval of 1.02 to 1.90 mm²/s. The TSS content varied between 7 and 22.50% in the Brix scale. Conclusion: Among the products tested, Colgate Plax Kids presented a high level of total soluble solids content (ºBrix), viscosity and endogenous pH below the critical consideration.

Cariogenicity of original and fruit juice-added soy beverages / Cariogenicidade de bebidas de soja originais e acrescidas de sucos de fruta

PURPOSE: To evaluate the cariogenic potential of soy-based drinks available in the Brazilian market. METHODS: Three soy-based beverages from different trademarks (Ades®, Mais Vita® and Sollys®) were evaluated. For each brand, 04 flavors were analyzed (original, pineapple, orange and grape juices). Total Soluble Solid Content (TSSC), Reducing Sugars (RS), Non-reducing Sugars (NRS) and Total Sugars (TS) contents were assessed. Analyses were performed in triplicate. Data gathered underwent analysis of variance (ANOVA), and type I error (α) was set at 0.05. RESULTS: TSSC values ranged between 8.25 and 15.00 ºBrix for all samples. There were no differences in TSSC levels between original and fruit juice-added soy drinks. RS have not been detected in any of the original soy beverages. Concerning to the drinks containing fruit juices, Mais Vita® grape significantly revealed the highest RS levels (P<0.05). For NRS and TS, analyses indicated Ades® and Mais Vita® original contain levels significantly (P<0.05) lower than the corresponding fruit juice-added drinks. CONCLUSION: There is no difference in TSSC values between original and fruit juice-added soy drinks and most beverages containing fruit-juices presented higher levels of TS and sucrose when compared to the original soy drink, what might lead to an increased cariogenic potential.

OBJETIVO: Avaliar o potencial cariogênico de bebidas à base de soja disponíveis no mercado brasileiro. METODOLOGIA: Três bebidas de soja de diferentes marcas comerciais (Ades®, Mais Vita® e Sollys®) e sabores (original, abacaxi, laranja e uva) foram analisadas. Verificaram-se os Teores de Sólidos Solúveis Totais (TSST) e de Açúcares Redutores (AR), Não-redutores (ANR) e Totais (AT). As análises foram realizadas em triplicata e os dados submetidos à Análise de Variância (ANOVA), com erro α de 0,05. RESULTADOS: Os valores TSST variaram de 8,25 a 15,00 ºBrix para todas as amostras, não havendo diferenças entre as bebidas originais e as acrescidas de sucos de fruta. Não foram detectados AR nas amostras de bebidas originais. Quanto às formulações contendo sucos de fruta, o Mais Vita® uva apresentou os mais altos níveis de AR (P<0,05). Quanto à ANR e AT, Ades® e Mais Vita® Originais revelaram teores significantemente menores que as bebidas acrescidas de sucos de fruta (P<0,05). CONCLUSÃO: Não houve diferença no TSST entre as bebidas de soja originais e as acrescidas de sucos de fruta. A maioria das formulações contendo suco de fruta apresentou teores mais altos de AT e sacarose quando comparados à respectiva bebida original, o que pode resultar em um maior potencial cariogênico do produto.

Comparative radiopacity of four low-viscosity composites

The aim of this study was to evaluate the radiopacity of four commercially available low-viscosity composites. The lowviscosity composites used in this study were Natural Flow, Flow It, Filtek Flow and Protect Liner F. Five specimens of each material were made in stainless-steel ring moulds of 10 mm diameter and 2 mm height. One specimen of each material and a 10-step aluminium wedge were radiographed in an occlusal film. The reading of the optical density was performed in five different locations in each radiographed specimen. The net optical density was calculated, and then the mean values were obtained, and related with the equivalent thickness of aluminium. The radiopacities of each composite, in millimeters of aluminium were: Flow It (3.24 ± 0.17); Filtek Flow (2.25 ± 0.17); Natural Flow (1.50 ± 0.13); Protect Liner F (<1 mm/Al). Flow It and Filtek Flow presented an acceptable radiopacity according to the ISO Standard 4049. Natural Flow and Protect Liner F did not supply the requirements for radiopacity, thus, these materials could be confounded with secondary caries in some clinical applications, such as restorations or cavity lining.