Effects of LED Lights on Bulk Fill Resin Polymerization

The present study analyzed the microhardness and degree of conversion of three Bulk Fill resins (M1 - Filtek Bulk Fill; M2 - Tetric N-Ceram Bulk Fill and M3 - Opus Bulk Fill) polymerized by single peak and polywave Light-emitting Diode Curing Lights. A total 90 test specimens (n=10) were obtained using a Teflon matrix for the purpose of testing microhardness; and for degree of conversion: 135 specimens (n=5) by using a 2 x 6 cm matrix. The specimens were light polymerized using 3 light sources (L1 - Optilight Max, L2 - Bluephase, L3 - VALO). They were kept in artificial saliva om an oven at 37±1°C during the experiment. The degree of conversion was measured by FTIR 24 h after obtaining each test specimen. The microhardness readouts were performed with a microdurometer at the time intervals of 48 hours (T0), 7 days (T1), 14 days (T2) and 21 days (T3). M1L3 was found to show the highest microhardness values in T2, and M1 showed the lowest degree of conversion in the deep third with L1. It was concluded that Filtek Bulk Fill resin showed the best results in comparison with the other resins.

El presente estudio analizó la microdureza y el grado de conversión de tres resinas Bulk Fill (M1 - Filtek Bulk Fill; M2 - Tetric N-Ceram Bulk Fill y M3 - Opus Bulk Fill) polimerizadas por lámparas de curado de diodo emisor de luz de pico único y polionda. Se obtuvieron un total de 90 especímenes de prueba (n=10) utilizando una matriz de teflón con el propósito de probar la microdureza; y para grado de conversión: 135 especímenes (n=5) utilizando una matriz de 2 x 6 cm. Las muestras se fotopolimerizaron utilizando 3 fuen- tes de luz (L1 - Optilight Max, L2 - Bluephase, L3 - VALO). Se mantuvieron en saliva artificial en estufa a 37 ±1°C durante el experimento. El grado de conversión se midió por FTIR 24 h después de obtener cada muestra de prueba. Las lecturas de microdureza se realizaron con un microdurómetro en los intervalos de tiempo de 48 horas (T0), 7 días (T1), 14 días (T2) y 21 días (T3). Se encontró que M1L3 mostraba los valores más altos de microdureza en T2, y M1 mostraba el grado más bajo de conversión en el tercio profundo con L1. Se concluyó que la resina Filtek Bulk Fill mostró los mejores resultados en comparación con las demás resinas.

Changes in the properties of bulk-fill resins under conditions of gastroesophageal reflux and bulimia

Aim: Evaluate the roughness, microhardness and color change of different Bulk Fill resins when submitted to the condition of gastroesophageal reflux and bulimia. Methods: 60 specimens (n = 10) of Bulk-Fill composite resins were made: M1 ­ Filtek™; M2 ­ Tetric N-Ceram and M3 ­ OPUS, through a matrix 2x6 mm and light cured by the VALO light source. After polishing, initial analyzes (48 hours - T0) of surface roughness (Ra), microhardness (VHN) and color change (ΔE) were performed. To simulate the oral condition of severe gastroesophageal reflux and bulimia, the specimens were immersed in hydrochloric acid (S1) (pH 1.7) 4 minutes a day, for 7 days. Control group specimens were immersed in artificial saliva (S2). Subsequently to immersions, mechanical brushing was performed for 3 minutes, three times a day, simulating 7 days of brushing. And again, the analyzes of Ra, VHN and ΔE were performed (7 days - T1). Thus, hydrochloric acid immersion, mechanical brushing and Ra analysis were repeated at 14 days (T2) and 21 days (T3); and T2, T3 and T4 (3 years) for VHN and ΔE. Results: After Shapiro-Wilk statistical test, ANOVA and Tukey test with Bonferroni adjustment (p>0.05), M3 showed the lowest Ra at all times compared to the other resins, while the highest Ra was at T0. M1 and T1 showed higher VHN. And M2 and T4 showed higher ΔE. Conclusion: Bulk Fill resins can be indicated for patients with Gastroesophageal Reflux and Bulimia, nonetheless, Tetric N-Ceram resin showed the worst results

Influence of NaHCO3 powder on color and roughness of the composite submitted to bleaching and euterpe oleracea / Influencia del polvo de NaHCO 3 en el color y rugosidad del composite sometido a blanqueo y euterpe oleracea

Aim: This study aims to evaluate the surface roughness and susceptibility to staining of bleached composite resin with 22% carbamide peroxide, as well as the effect of subsequent prophylaxis with NaHCO3 powder. Material and Methods: Forty disk-shaped (2 × 6 mm) specimens of composite resin (Z250 XT) were prepared. Half of the specimens were subjected to bleaching with 22% carbamide peroxide, and the other half were stored in artificial saliva. In sequence, all specimens were immersed in acai juice (Euterpe oleracea) for 4 h for 14 days, and subdivided into two groups. Group 1 samples were subjected to prophylaxis treatment, while group 2 samples were subjected to treatment with artificial saliva. Surface roughness (Ra) and color (ΔE*) were measured after polishing (T0), bleaching (T1), immersion in acai juice (T2), and application of NaHCO3 powder (T3) using a profilometer and a spectrophotometer. Results: Statistical analyses (analysis of variance and Tukey's test, p≤0.05) revealed that regarding color there was statistically significance for the factors in isolation, except for the factor bleaching. For both color and surface roughness there was statistically significant difference for the interaction, except for the interaction between NaHCO3 power and bleaching. Conclusion: The NaHCO3 air-powder polishing decreases the staining of the composite resin; however, it increases the surface roughness. With respect to the color variable, the whitening factor had no significant effect on the tested material; however, it increases surface roughness.

Objetivo: Este estudio tiene como objetivo evaluar la rugosidad de la superficie y la susceptibilidad a la tinción de la resina compuesta blanqueada con peróxido de carbamida al 22%, así como el efecto de la profilaxis posterior con polvo de NaHCO3. Material y Métodos: Se prepararon cuarenta especímenes en forma de disco (2 × 6 mm) de resina compuesta (Z250 XT). La mitad de los especímenes se sometieron a blanqueo con peróxido de carbamida al 22% y la otra mitad se almacenó en saliva artificial. En secuencia, todos los especímenes se sumergieron en jugo de acai (Euterpe oleracea) durante 4h durante 14 días, y se subdividieron en dos grupos. Las muestras del grupo 1 se sometieron a tratamiento profiláctico, mientras que las muestras del grupo 2 se sometieron a tratamiento con saliva artificial. La rugosidad de la superficie (Ra) y el color (ΔE*) se midieron después del pulido (T0), el blanqueo (T1), la inmersión en jugo de acai (T2) y la aplicación de polvo de NaHCO3 (T3) utilizando un perfilómetro y un espectrofotómetro. Resultados: Los análisis estadísticos (análisis de varianza y prueba de Tukey, p≤0.05) revelaron que en relación al color hubo significancia estadística para los factores en forma aislada, excepto para el factor blanqueamiento. Tanto para el color como para la rugosidad de la superficie hubo una diferencia estadísticamente significativa para la interacción, excepto para la interacción entre el poder de NaHCO3 y el blanqueo. Conclusión: El pulido al aire con polvo de NaHCO3 disminuye el manchado de la resina compuesta; sin embargo, aumenta la rugosidad de la superficie. Con respecto a la variable color, el factor de blanqueamiento no tuvo efecto significativo sobre el material ensayado; sin embargo, aumenta la rugosidad de la superficie.

Effect of Color and Surface Roughness of Glass Ionomer Cements Submitted to Solutions Based on Ilex paraguariensis

ABSTRACT: The present study analyzed the color change (DE) and surface roughness (Ra) of glass ionomer cements (GICs) subjected to typical herbaceous South American beverage action - Ilex paraguariensis. 90 specimens (n = 10) were made: M1 - GIC Riva Light Cure® (SDI); M2 - GIC Riva Self Cure® (SDI); M3 - GIC Vitremer® (3M ESPE). After light curing/ polymerization of GICs, specimens were divided for being submitted to solutions for one hour a day for 21 days: S1 - Yerba Mate Pajarito Traditional (Pajarito); S2 - Erva Mate Chimarrão (Barão de Cotegipe); S3 - Water (control). Four DE and Ra readings were taken: T0 - initial; T1 - 7 days; T2 - 14 days and T3 - 21 days, with a spectrophotometer and a roughness meter respectively. The obtained data were submitted to ANOVA statistical analysis and Bonferroni. S1 and S2 at T1 and T2 there was no statistical difference between the materials, and at T3 Materials M1=M2, M1=M3, and M2>M3. For S3 at T1, T2 and T3 there was no difference between the materials. Analyzing surface roughness, there was no statistical significance. Concluded that all materials changed color with greater influence of time, but without changing surface roughness.

RESUMEN: En el presente estudio se analizó el cambio de color (DE) y la rugosidad superficial (Ra) de los cementos ionómero de vidrio (CIV) sometidos a la acción típica de las bebidas herbáceas sudamericanas - Ilex paraguariensis. Se realizaron 90 especímenes (n = 10): M1 - GIC Riva Light Cure® (SDI); M2 - GIC Riva Self Cure® (SDI); M3 - GIC Vitremer® (3M ESPE). Después de la fotopolimerización/ polimerización de los CIV, los especímenes se dividieron y fueron sometidos a soluciones durante una hora al día durante 21 días: S1 - Yerba Mate Pajarito Tradicional (Pajarito); S2 - Erva Mate Chimarrão (Barão de Cotegipe); S3 - Agua (control). Se tomaron cuatro lecturas de DE y Ra: T0 - inicial; T1 - 7 días; T2 - 14 días y T3 - 21 días, con espectrofotómetro y rugosímetro respectivamente. Los datos obtenidos fueron sometidos a análisis estadístico ANOVA y Bonferroni. S1 y S2 en T1 y T2 no hubo diferencia estadística entre los materiales y en T3 Materiales M1=M2, M1=M3 y M2>M3. Para S3 en T1, T2 y T3 no hubo diferencia entre los materiales. Al analizar la rugosidad de la superficie, no hubo significación estadística. En conclusion, todos los materiales cambiaron de color con mayor influencia del tiempo, pero sin cambiar la rugosidad de la superficie.

Effect of desensitizing dentifrices on eroded dentin wettability / Efeito de dentifrícios dessensibilizantes na molhabilidade da dentina erodida

Objective: To analyze the wettability on the surface of eroded dentin in teeth submitted to abrasive wear with desensitizing dentifrices. Material and Methods: Bovine dentin specimens were polished and immersed in 10 mL of citric acid (pH=3.2) for 2 h. The eroded specimens were submitted to mechanic brushing according to the 4 dentifrices adopted: Colgate Total (control); Colgate Sensitive Pro-Relief; Sensodyne Repair & Protect; or Sensodyne Rapid Relief. Afterwards, it was conditioned in 37% aqueous phosphoric acid solution. Wettability of 80 specimens (n=10) brushed for 7 or 21 days was evaluated by measuring the contact angle between the dentin surface and a drop of the adhesive Single Bond Universal® (3M) with a goniometer. Changes in the surface morphology of 12 specimens (n = 3) brushed for 21 days were followed by confocal laser scanning microscopy (CLSM). Data were analyzed by two-way ANOVA and Tukey test (p > 0.05). Results: Groups treated with desensitizing dentifrices did not differ significantly (p ≤ 0.05). Surface treatment and abrasive wear did not interact significantly (p ≤ 0.05). Brushing along 7 days gave the smallest contact angle value (p ≥ 0.05). CLSM images showed morphological changes for all the groups. Conclusion: The desensitizing dentifrices did not interfere in eroded dentin wettability after brushing along 7 or 21 days. Brushing with any of the dentifrices along 21 days promoted open dentinal tubules.(AU)

Objetivo: Analisar a aplicação de um adesivo na superfície de dentina erodida em dentes submetidos ao desgaste abrasivo com agentes dessensibilizantes. Material e Métodos: Espécimes de dentina bovina foram polidos e imersos em 10 mL de ácido cítrico (pH=3,2) por 2 h. Os espécimes erodidos foram submetidos à escovação mecânica de acordo com os 4 dentifrícios adotados: Colgate Total (controle); Colgate Sensitive Pro-Alívio; Sensodyne Repair & Protect; ou Sensodyne Rápido Alívio. Em seguida, foram condicionados em ácido fosfórico a 37%. A molhabilidade de 80 espécimes (n=10) escovados por 7 ou 21 dias foi avaliada medindo-se o ângulo de contato entre a superfície dentinária com uma gota do adesivo Single Bond Universal® (3M) por um goniômetro. Alterações na morfologia da superfície de 12 espécimes (n = 3) escovados por 21 dias foram seguidos por Microscopia Confocal de Varredura a Laser (MCVL). Os dados foram analisados por ANOVA dois fatores e teste de Tukey (p > 0,05). Resultados: Os grupos tratados com dentifrícios dessensibilizantes não diferiram significativamente (p ≤ 0,05). O tratamento de superfície e o desgaste abrasivo não interagiram significativamente (p ≤ 0,05). A escovação ao longo de 7 dias apresentou o menor valor de ângulo de contato (p ≥ 0,05). As imagens do MCVL mostraram alterações morfológicas para todos os grupos. Conclusão: Os dentifrícios dessensibilizantes não interferiram na molhabilidade da dentina erodida após escovação ao longo de 7 ou 21 dias. A escovação com qualquer um dos dentifrícios ao longo de 21 dias promoveu a abertura dos túbulos dentinários (AU)

Is there a preferable management for root caries in middle-aged and older adults? A systematic review.

Aim This systematic review aimed to critically summarise the results of clinical studies investigating agents able to: stop the progression of carious lesions; stop the development of new root carious lesions; preserve the vitality of the infected dental tissues; and increase the surface hardness or change of surface texture, in middle-age and older adults.Methods PubMed, Scopus, and Web of Science were searched systematically, following PRISMA guidelines. Clinical trials published from 2011 to 2020 (March) were included. This systematic review is registered in the PROSPERO database (CRD42018104399). Languages were restricted to English.Results Thirteen of 312 studies were eligible for this review. Eight agents were identified in the studies and their efficacy was assessed using different methods. The agents that presented valuable results on preventing or arresting root caries were 38% silver diamine fluoride (SDF), arginine-containing toothpaste and high-fluoride toothpastes.Conclusions Based on the selected studies' findings, annual applications of 38% SDF could be the most effective treatment for root caries in older adults. In addition, the daily use of a 1.5% arginine toothpaste or a high-fluoride toothpaste could also be recommended. More research on root caries-specific diagnostic methods, especially at very early stages, is necessary.

Microhardness and surface roughness of Biodentine exposed to mouthwashes.

Aim: This study evaluates Vickers microhardness and surface roughness in Biodentine cement (M1) and glass-ionomer cement Fuji IX (M2), both immersed in mouthwash. Materials and Methods: Fifty-four samples were randomly distributed in distilled water (S1), Listerine Cool Mint (S2), and Colgate Plax (S3). Each sample was put in a flask with mouthwash for 2 min, under vibration, twice a day for 21 days. Microhardness and surface roughness were assessed at 48 h (T0), 7 days (T1), 14 days (T2), and 21 days (T3). Results: For roughness: time (T), solution (S) and material (M), TxM, and SxM and for microhardness: M, TxS, TxM, and SxM were statistically significant. T3, M1, M1T3, and M1S1 presented the highest surface roughness. M2, M1T0, M1T1, M1T2, M1S1, and M1S2 presented higher microhardness. Conclusion: Biodentine showed higher surface roughness for T1, T2, and T3 and higher microhardness for T0, T1, and T2 against Fuji IX. Biodentine presented higher microhardness independently of solution.

Color evaluation of a resin cement light polymerized by different light sources and submitted to potentially staining beverages / Avaliação da cor de um cimento resinoso fotopolimerizado por diferentes fontes de luz e submetidos a bebidas potencialmente corantes

Introduction: The color stability of resin cements, whether dual-pre-cured or photopolymerizable, as well as the color of the dental substrate, are fundamental for the aesthetic success of ceramic restorations, since the ceramic presents a high level of translucency due to its small thickness. Objective: The aim of this in vitro study was to evaluate the color of a resin cement light polymerized by different light sources and immersed in potentially staining beverages. Material and method: Were made 42 specimens of resin cement Variolink-Esthetic (2×6mm) (n=7), being half polymerized with LED light (F1) and half with Halogen light (F2). The specimens were stored in artificial saliva at 37 °C±1 °C. After 24 hours, they were polished with abrasive discs, and divided for the purpose of being submitted to the different solutions for 2 minutes per day, for 28 days, as follows: S1 - Coca-Cola; S2 - Red Wine; and S3 - Distilled Water (Control). Five color readouts were taken: T0 - initial; T1 - 7 days; T2 - 14 days; T3 - 21 days; and T4 - 28 days; with a spectrophotometer (Model SP62S). The color change data (ΔE*) were submitted to statistical analysis, ANOVA and Tukey (p≤0.05). Result: Analyzing the factor solution, S2 (5.89 (±0.02)), produced a higher ΔE* value than S1 (3.79 (±0.02)) and (S1), a higher value than S3 (1.41 (±0.02)). Analyzing the factor light source, F2 (4.05 (±0.12)), produced a higher ΔE* value than F1 (3.33 (±0.12)). When analyzing the factor time, ΔE* values were found to increase gradually over the course of time: T1(2.36 (±0.08)); T2(3.27 (±0.08)); T3(4.06 (±0.08)); and T4(5.09 (±0.08)). Conclusion: It was concluded that red wine produced a greater color change; Halogen light promoted highest degree of pigmentation; and the longer the time of immersion, the greater the color change of the material.

Introdução: A estabilidade de cor dos cimentos resinosos, sejam eles de presa dual ou fotopolimerizáveis, assim como a cor do substrato dental, são fundamentais para o sucesso estético das restaurações cerâmicas uma vez que a cerâmica apresenta alto nível de translucidez devido a sua pequena espessura. Objetivo: O objetivo deste estudo in vitro foi avaliar a cor de um cimento resinoso fotopolimerizado por diferentes fontes de luz e imersos em bebidas potencialmente corantes. Material e método: Foram confeccionados 42 espécimes do cimento resinoso Variolink-Esthetic (2×6mm) (n=7), sendo metade fotopolimerizado com luz LED (F1) e metade com luz Halógena (F2). Os espécimes foram mantidos em saliva artificial à 37 °C±1 °C. Após 24 horas, foram polidos com discos abrasivos e subdivididos para serem imersos 2 minutos por dia, durante 28 dias, nas diferentes soluções: S1 - Coca-Cola; S2 - Vinho Tinto; e S3 - Água destilada (controle). Foram realizadas 5 leituras de cor: T0 - inicial; T1 - 7 dias; T2 - 14 dias; T3 - 21 dias; e T4 - 28 dias; com auxílio de um espectrofotômetro (modelo SP62S). Os dados de alteração de cor (ΔE*) foram submetidos a análise estatística, ANOVA e Tukey (p≤0,05). Resultado: Analisando o fator solução, S2 (5,89 (±0,02)), proporcionou maior ΔE* que S1 (3,79 (±0,02)) e este (S1), maior que S3 (1,41 (±0,02)). Analisando o fator fonte de luz, F2 (4,05 (±0,12)), proporcionou maior ΔE* que F1 (3,33 (±0,12)). E analisando o fator tempo, obteve-se que ΔE* foi gradativamente aumentando no decorrer do tempo: T1(2,36 (±0,08)); T2(3,27 (±0,08)); T3(4,06 (±0,08)); e T4(5,09 (±0,08)). Conclusão: Conclui-se que o vinho tinto promoveu maior alteração de cor; a luz Halógena promoveu maior pigmentação e; quanto maior o tempo de imersão, maior alteração de cor do material.

Bond strength of resin cements to novel materials to intracanal posts applications / Resistência de união de cimentos resinosos a novos materiais para pinos intrarradiculares

Objective: Evaluate the bond strength of resin cements to new materials for application in intraradicular posts. Material and Methods: Five materials were evaluated: fiberglass, PET, polyethylene, polyacetal and PTFE. Two commercial resin cements (Rely X U200 and Rely X Arc) were applied on the test specimens of the materials (9x3mm) and the bonding was evaluated through the shear bond strength test, where the chisel operated with a load of 1kN and a velocity of 0.5mm/min at the cement/material interface. The data were analyzed by the Shapiro-Wilk test, followed by the two-way analysis of variance, performed with the Bonferroni post-test (α=0.05). Results: The glass fiber was statistically different from all evaluated materials (p0.05). Comparing the two cements, a statistical difference was found between Rely X U200 and Arc only for the glass fiber (p=0). Conclusion: PET, polyethylene, polyacetal and PTFE exhibited reduced bond strength compared to the glass fiber (AU)

Objetivo: Avaliar a resistência de união de cimentos resinosos a novos materiais para aplicação em pinos intrarradiculares. Material e método: Foram avaliados cinco materiais: fibra de vidro, PET, polietileno, poliacetal e PTFE. Dois cimentos resinosos comerciais (Rely X U200 e Rely X Arc) foram aplicados sobre os corpos de prova dos materias (9x3mm) e a resistência de união foi avaliada através do teste de cisalhamento, onde o cinzel atuou com carga de 1kN e velocidade de 0,5mm/min na interface cimento/material. Verificada a normalidade dos dados através do teste Shapiro-Wilk, foi realizada a análise de variância de dois fatores com pós-teste de Bonferroni (α=0,05). Resultados: a fibra de vidro foi diferente estatisticamtente de todos os materiais avaliados (p0,05). Comparando-se os dois cimentos, foi encontrada diferença estatística entre o Rely X U200 e Arc apenas para a fibra de vidro (p=0). Conclusão: PET, polietileno, poliacetal e PTFE apresentaram resistência de união reduzida comparando-se à fibra de vidro. (AU)

Surface roughness of composite resins subjected to hydrochloric acid.

The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence. Acid challenge was performed by immersion of specimens in hydrochloric acid (pH 1.2) for 1 min, 4 times per day for 7 days. The specimens not subjected to acid challenge were stored in 15 mL of artificial saliva at 37 oC. Afterwards, all specimens were submitted to abrasive challenge by a brushing cycle performed with a 200 g weight at a speed of 356 rpm, totaling 17.8 cycles. Surface roughness measurements (Ra) were performed and analyzed by ANOVA and Tukey test (p≤0.05). Surface roughness values were higher in the presence (1.07±0.24) as compared with the absence of hydrochloric acid (0.72±0.04). Surface roughness values were higher for microhybrid (1.01±0.27) compared with nanofilled (0.68 ±0.09) and nanohybrid (0.48±0.15) composites when the specimens were not subjects to acid challenge. In the presence of hydrochloric acid, microhybrid (1.26±0.28) and nanofilled (1.18±0,30) composites presents higher surface roughness values compared with nanohybrid (0.77±0.15). The hydrochloric acid affected the surface roughness of composite resin subjected to brushing.

Surface Roughness of Composite Resins Subjected to Hydrochloric Acid

The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence. Acid challenge was performed by immersion of specimens in hydrochloric acid (pH 1.2) for 1 min, 4 times per day for 7 days. The specimens not subjected to acid challenge were stored in 15 mL of artificial saliva at 37 oC. Afterwards, all specimens were submitted to abrasive challenge by a brushing cycle performed with a 200 g weight at a speed of 356 rpm, totaling 17.8 cycles. Surface roughness measurements (Ra) were performed and analyzed by ANOVA and Tukey test (p≤0.05). Surface roughness values were higher in the presence (1.07±0.24) as compared with the absence of hydrochloric acid (0.72±0.04). Surface roughness values were higher for microhybrid (1.01±0.27) compared with nanofilled (0.68 ±0.09) and nanohybrid (0.48±0.15) composites when the specimens were not subjects to acid challenge. In the presence of hydrochloric acid, microhybrid (1.26±0.28) and nanofilled (1.18±0,30) composites presents higher surface roughness values compared with nanohybrid (0.77±0.15). The hydrochloric acid affected the surface roughness of composite resin subjected to brushing.

Este estudo avaliou a influencia do ácido clorídrico na rugosidade superficial de resinas compostas submetidas a escovação. Sessenta corpos de prova medindo 2 mm de espessura x 6 mm de diâmetro foram confeccionados e utilizados como unidades experimentais. O presente estudo envolve uma análise fatorial 3x2, onde os fatores foram resina composta (n=20), com 3 níveis: resina composta microhíbrida (Z100), nanoparticulada (Filtek TM Supreme) e nanohíbrida (Ice); e desafio ácido (n=10), com 2 níveis: ausência e presença. O desafio ácido foi realizado por meio da imersão em ácido clorídrico (pH 1,2) por 4 h diárias, 1 min cada imersão, durante 7 dias. Os espécimes que não foram submetidos ao desafio ácido foram armazenados em 15 mL de saliva artificial a 37 °C. Todos os espécimes foram submetidos ao desafio abrasivo. O processo de escovação foi realizado com 200 g de peso, com velocidade de 356 rpm, totalizando 17,8 ciclos. As medidas de rugosidade superficial (Ra) foram realizadas e analisadas por meio da ANOVA e teste de Tukey (p<0,05). Os valores de rugosidade superficial foram maiores na presença (1,07±0,24)quando comparado com a ausencia do ácido hidroclorídrico (0,72±0,04). A resina microhíbrida (1,01±0,27) apresentou maior rugosidade superficial que as resinas nanoparticulada (0,68±0,09) e nanohíbrida (0,48±0,15) quando os espécimes não foram submetidos ao desafio ácido. Na presença do ácido hidroclorídrico, a resina microhíbrida (1,26±0,28) e a resina nanoparticulada (1,18±0,30) apresentou maior valor de rugosidade superficia comparado com a resina nanohíbrida (0.77±0.15). O ácido hidroclorídrico influenciou a rugosidade superficial da resina composta submetida a escovação.

The influence of mouthrinses and simulated toothbrushing on the surface roughness of a nanofilled composite resin

The aim of this study was to determine the influence of mouthrinses on the surface roughness of a nanofilled composite resin after toothbrushing. One hundred nanofilled composite resin specimens were prepared and randomly distributed into two groups-brushed and non-brushed-and then assigned to five subgroups, according to the mouthrinse solutions (n = 10): Colgate Plax Fresh Mint, Oral B, Cepacol, Colgate Plax, and artificial saliva. Each sample was immersed in 20 mL of the mouthrinses for 1 minute, 5 days per week, twice a day, for a 3-week period. The control group used in the study was one in which the specimens were not subjected to brushing and remained only in artificial saliva. Toothbrushing was performed once a week for 1 minute, for 3 weeks. Surface roughness measurements (Ra) were performed after the immersion period and toothbrushing, by means of a profilometer. Data were analyzed by two-way ANOVA and Tukey's test. Analysis revealed that the association between toothbrushing and Colgate Plax Fresh Mint produced the lowest surface roughness (p < 0.05). All other groups tested (Oral B, Cepacol, Colgate Plax, artificial saliva) exhibited no statistically significant differences between surfaces, whether subjected to toothbrushing or not (p < 0.05). It was concluded that the surface roughness of the nanofilled composite resin tested can be influenced by the mouthrinse associated with toothbrushing.

The influence of mouthrinses and simulated toothbrushing on the surface roughness of a nanofilled composite resin.

The aim of this study was to determine the influence of mouthrinses on the surface roughness of a nanofilled composite resin after toothbrushing. One hundred nanofilled composite resin specimens were prepared and randomly distributed into two groups-brushed and non-brushed-and then assigned to five subgroups, according to the mouthrinse solutions (n = 10): Colgate Plax Fresh Mint, Oral B, Cepacol, Colgate Plax, and artificial saliva. Each sample was immersed in 20 mL of the mouthrinses for 1 minute, 5 days per week, twice a day, for a 3-week period. The control group used in the study was one in which the specimens were not subjected to brushing and remained only in artificial saliva. Toothbrushing was performed once a week for 1 minute, for 3 weeks. Surface roughness measurements (Ra) were performed after the immersion period and toothbrushing, by means of a profilometer. Data were analyzed by two-way ANOVA and Tukey's test. Analysis revealed that the association between toothbrushing and Colgate Plax Fresh Mint produced the lowest surface roughness (p < 0.05). All other groups tested (Oral B, Cepacol, Colgate Plax, artificial saliva) exhibited no statistically significant differences between surfaces, whether subjected to toothbrushing or not (p < 0.05). It was concluded that the surface roughness of the nanofilled composite resin tested can be influenced by the mouthrinse associated with toothbrushing.

Efecto de diferentes técnicas de pulido y refrigeración en la rugosidad superficial de una resina nanohíbrida / Effect of different techniques of cooling and polishing the surface roughness of a composite resin nanohíbrida

El objetivo de este trabajo in vitro fue evaluar la rugosidad superficial de una resina compuesta nanohíbrida (Tetric N Ceram®) utilizando 3 técnicas de acabado superficial, con y sin refrigeración. Materiales y método: Fueron confeccionados 60 especimenes (n=10), obtenidos por medio de una matríz metálica (10 x 2 mm). Los especímenes fueron almacenados durante 24 horas en agua destilada a temperatura ambiente, siendo posteriormente divididos en 6 grupos: G1- astropol + refrigeración, G2-astrobrush + refrigeración, G3- astropol + astrobrush + refrigeración, G4-astropol sin refrigeración, G5-astrobrush sin refrigeración, G6- astropol + astrobrush sin refrigeración. La lectura de la rugosidad superficial (Ra) fue realizada 24 horas luego de los respectivos tratamientos por medio de un rugosímetro marca Mitutoyo, tipo SJ - 201P (Japón). Resultados: Los datos fueron sometidos al test de ANOVA (p?0,05) y demostraron que no existe diferencias estadísticamente significantes entre las diferentes técnicas de pulido y refrigeración. Conclusión: La técnica de pulido y refrigeración no interfiere en la rugosidad superficial, por tanto se debe tener en consideración las demás propiedades físicas de las resinas compuestas y el aspecto biológico del diente

The study evaluated in vitro the surface roughness in a nanohibrid composite resin (Tetric N Ceram®) polished with the use three polishing techniques with and without refrigeration. Materials and Methods: Sixty discs (n=10), was made with aid of a metal matrix measuring 10 x 2 mm. The specimens were stored in artificial saliva in an oven at 37oC (±1 oC), for 24 hours. After this time the specimens were submitted to action of astropol + refrigeration (G1), astrobrush + refrigeration (G2), astropol + astrobrush + refrigeration(G3), astropol whithout refrigeration (G4), astrobrush whithout refrigeration (G5), astropol + astrobrush whithout refrigeration (G6). The surface roughness (Ra) of the specimens was avaliated after 24 hours using profilometer (Mitutoyo SJ - 201P - Japon). Results: the data were submitted to Analysis of Variance ANOVA (p?0,05) and were no statistically significant differences detected for each technique. Conclusion: The effect polishing techniques and refrigeration not interferance in the surface roughness, but needed consideration of others properties

Estudio comparativo de la microdureza de composites en relación a la fuente de luz, profundidad de polimerización y tiempo / Comparative study of microhardness of composites in relation to the light source, depth of cure and time

Evaluar la microdureza de las resinas Charisma (microhíbrida) y Z100 (híbrida) en relación a la profundidad de polimerización (8, 6, 4, 2 mm e 0 mm-superficial), la fuente de luz (Diodo emisión de luz-LED y Luz halógena de cuarzo-tungsteno-QTH) y los tiempos de análisis (inmediato, 24 h y 1 mes). Fueron testadas resinas Charisma (Kulzer) y Z100 (3M/ESPE). Para la realización del ensayo de microdureza fueron confeccionados 07 cuerpos de prueba de 8x2x4mm en matriz de carbono, con incrementos de 1mm cada y fotopolimerizados con los aparatos Optilux (Dabi Atlante) y LED (MMOptic). Los cuerpos de prueba fueron sometidos a los ensayos de dureza Vickers; inmediato, 24 horas y 1 mes después de la confección, almacenados en agua destilada y estufa a 37 1ºC. El análisis de microdureza fue realizada por medio del microdurómetro Shimadzu HMV-2000, con 5s de indentación y 500g de peso. La dureza fue evaluada en diferentes profundidades (superficie externa, 2, 4, 6 y 8 mm). Los resultados fueron estadísticamente significantes (p=5%) para todas las condiciones experimentales. Ambas resinas tuvieron la microdureza disminuida conforme el aumento de la profundidad y presentaron valores mayores con el aparato de luz halógena que con el aparato de diodo. La resina Z100 presento mayores valores de microdureza en relación a la resina Charisma. De acuerdo con los resultados, se puede concluir que cuanto mayor la profundidad menor la dureza y el aparato QTH proporcionó mayor grado de polimerización

To evaluate the microhardness of the resins Charisma (microhybrid) and Z100 (hybrid) in respect to the depth of polymerization (8, 6, 4, 2 mm and 0 mm-superficial), the source of light (Emitting Diode of light-LED and halogenous quartz-tungsten-QTH Light) and the analysis times (immediate, 24 h and 1 month). Resins Charisma (Kulzer) and Z100 were tested (3M/ESPE). For the accomplishment of the microhardness essay 07 were confectioned body-of-test of 8x2x4mm in carbon matrix, with increments of 1mm each and photopolymerised with Optilux devices (Dabi Atlante) and LED (MMOptic). The body-of-test was submitted to the essays of Vickers hardness; immediate, 24 hours and 1 month after the confection, stored in distiled water and heat 37±1ºC. The microhardness analysis was accomplished by means of the microdurometer Shimadzu HMV-2000, with 5s and 500g of load. The hardness was evaluated in different depths (external surface, 2, 4, 6 and 8 mm). The results were statistically significant (p=5%) for all the experimental conditions. Both resins had had the microhardness diminished as the increase of the depth and had presented bigger values with the device of halogenous light that with the diode device. The Z100 resin presented greaters values of microhardness in respect to the Charisma resin. In accordance with the results, it can be concluded that how much bigger the depth lesser the hardness and device QTH provided to greater polymerization degree

Influence of NaHCO3 powder on translucency of microfilled composite resin immersed in different mouthrinses.

UNLABELLED: The regular use of mouthrinses, particularly when combined with the use of air-powder polishing, could affect the appearance of tooth-colored restorations. The current study sought to evaluate the effect of NaHCO(3) powder on translucency of a microfilled composite resin immersed in different mouthrinses, at distinct evaluation periods. Eighty disk-shaped specimens of composite resin (Durafill VS, Heraeus Kulzer GmbH & Co. KG, Hanau, Germany) were prepared. The composite specimens were then randomly allocated into two groups according to the surface treatment: exposure to NaHCO3 powder (10 seconds) or nonexposure, and they were randomly assigned into four subgroups, according to the mouthrinses employed (N = 10): Periogard (Colgate/Palmolive, São Bernardo do Campo, SP, Brazil), Cepacol (Aventis Pharma, São Paulo, SP, Brazil), Plax (Colgate/Palmolive), and distilled water (control group). The samples were immersed for 2 minutes daily, 5 days per week, over a 4-month test period. Translucency was measured with a transmission densitometer at seven evaluation periods. Statistical analyses (analysis of variance and Tukey's test) revealed that: distilled water presented higher translucency values (86.72%); Periogard demonstrated the lowest translucency values (72.70%); and Plax (74.05%) and Cepacol (73.32%) showed intermediate translucency values, which were statistically similar between them (p > 0.01). NaHCO3 air-powder polishing increased the changes in translucency associated with the mouthrinses. Air-powder polishing alone had no effect on material translucency. Translucency percent was gradually decreased from 1 week of immersion up to 4 months. It may be concluded that the NaHCO3 powder and the tested mouthrinses have affected the translucency of microfilled composite resin, according to the tested time. CLINICAL SIGNIFICANCE: During the last decade, the demand for composite resin restorations has grown considerably, however, controversy persists regarding the effect of surface roughness on color stability.

Resistência flexural e rugosidade superficial de resinas acrílicas utilizadas para confecção de placas oclusais / Flexural strength and superficial roughness of acrylic resins used for confection of occlusal splints

O objetivo deste trabalho foi avaliar in vitro o efeito da adição de fibras de vidro na resistência flexural por três pontos e rugosidade superficial de resinas utilizadas para a confecção de placas oclusais. Para este estudo, foram utilizadas as seguintes resinas com diferentes tipos de polimerização: resina acrílica autopolimerizável Vipi Flash® (RA), resina acrílica termopolimerizável por banho de água Vipi Cril® (RT) e resina acrílica termopolimerizável por calor de microondas Vipi Wave® (RM),com e sem adição de fibras de vidr (FV). Hipóteses em estudo: a adição de fibras de vidro aumenta a resistência flexural por três pontos e a rugosidade superficial dos corpos-de-prova. Foram confeccionadas doze amostras (n = 12) para cada grupo, a partir de uma matriz metálica com 67 mm de comprimento x 12,60 mm de largura x 3,00 mm de espessura. Os corpos-de-prova foramsubmetidos ao teste de resistência flexural em máquina de ensaio universal (EMIC DL 2000®), a uma velocidadede 5 mm/min, e ao teste de rugosidade superficial em rugosímetro (Mitutoyo®). Os dados foram submetidos à análise de variância e ao teste complementar de Tukey (p < 0,01). De acordo com os resultados, em relação à resistência flexural (MPa) houve diferença estatisticamente significativa somente para o fator tipo de polimerização das resinas (RA = 81,54 ± 4,94, RT = 92,86± 16,85, RM = 86,24 ± 8,89). Em relação à rugosidade superficial (RA-μm), houve diferença para os dois fatores fatores avaliados: tipo de polimerização (RA = 0,10 ± 0,02, RT = 0,13 ± 0,03, RM = 0,11 ± 0,13) e adição de fibras de vidro (CF = 0,13 ± 0,02, SF = 0,10 ± 0,11). Pode-se concluir que a adição de fibras de vidro aos grupos experimentais não alterou os valores de resistência flexural, no entanto aumentou os valores de rugosidade superficial das amostras testadas

A Singular Method to Compare Dental Radiographic Films Used to Study Maxillofacial Structures / Un Singular Método Comparativo de Radiografías Dentales Usadas en Estudios de Estructuras Maxilofaciales

The aim of this article is to present a singular and practical method to compare roentgenograms, concerning optical density and contrast. This method is specifically indicated for research related to stepwedge penetrometer and photodensitometer.

El objetivo de este artículo es presentar un método singular y práctico para comparar roentgenogramas, referentes a la densidad óptica y al contraste. Este método se indica específicamente para la investigación con el penetrómetro stepwedge y el fotodensitómetro.

Densidad osea bilateral comparativa del ángulo de la mandíbula / Comparative bilateral bone density of the mandible angle

The aim of this study was to assess a bilateral comparison of the mandible density in both sex young patients with computer densitometry. Fifty panoramic radiographs were obtained from young patients with ages between 18 and 23 years old (group A = 25 female and group B = 25 male) standardized, using the same X-Ray equipment (Siemens, lOKvp, 7mA), scanned with a 282.110 pixels resolution, and transferred later to a computer and using the SIDEXIS (Sirona, USA) program to analyze the bone densitometry performance. Bilateral sites were standardized with the objective to measure the bone density. Obtained data were registered and submitted to statistical analysis. The following means and standard deviations were obtained, in pixels, for the right and the left side, respectively: group A= 154.36 +/- 36.90 e 186.12 +/- 31.41, group B= 162.07 +/- 34.94 and 180.15 +/- 30.96. These values show statistical difference between different sides and groups (p<0.05), with a higher bone density on the left side in both groups, especially in group A.

El objetivo de este estudio fue realizar una comparación bilateral de la densidad de mandíbula en pacientes jóvenes de ambos sexos con computadora densitométrica ósea. Fueron obtenidas 50 radiografías panorámicas de pacientes jóvenes entre 18 y 23 años de edad (Grupo A = 25 femenino y el grupo B = 25 masculino), utilizando el mismo equipo de radiografía (Siemens, 1 OKvp, 7mA). Se escaneó con una resolución de 282,110 pixels, transfiriéndose luego a un computador para el estudio por medio del programa SIDEXIS (Sirona, USA) para analizar el desempeño densitométrico de hueso. Los sitios bilaterales fueron estandarizados con el objetivo de medir la densidad de hueso. Los datos obtenidos fueron registrados y sometidos a análisis estadístico. Las medias y los desvíos padrón fueron obtenidos en pixels, para el lado derecho y el lado izquierdo, respectivamente: Grupo A = 154,36 +/-36,90 y 186,12 +/- 31,41, grupo B = 162,07 +/- 34,94 y 180,15 +/- 30,96. Estos valores muestran la diferencia estadística entre lados y grupos diferentes (p<0,05), con una densidad más alta de hueso en el lado izquierdo en ambos grupos, especialmente en grupo A.

Avaliaçäo das condiçöes e satisfaçäo com as próteses em idosos da regiäo central do estado de Säo Paulo (Brasil) / Evaluation of the prosthetic condition and satisfation in elderly carriers of complete dentures in the State of Säo Paulo central region (Brazil)

Com o objetivo de caracterizar as condiçöes das próteses, realizou-se um trabalho com idososo usuários de prótese totais que freqüentaram o Centro de Reabilitaçäo do SUS da cidade de Araraquara, no primeiro do semestre do ano de 1999. Participaram 103 pessoas com mais de 60 anos, que responderam a um formulário abordando questöes referentes à saúde bucal e submeteram-se a exame clínico. Obtiveram-se estes resultados: 32 por cento dos idosos näo procuravam o serviço odontológico havia mais de 20 anos, 38,8 por cento usavam as mesmas próteses havia mais de 20 anos e 64 por cento das próteses se encontravam em estado näo funcional. Verificou-se ainda que mais de 50 por cento dos idosos relataram estar insatisfeitos com seus aparelhos protéticos pelos seguintes motivos: as próteses estavam soltas (31 por cento), näo conseguiam cortar os alimentos (24 por cento), estavam gastas (24 por cento), traumatizavam (18 por cento), possuíam fraturas (8 por cento) e razöes estéticas (4 por cento)